diff --git a/backend/2of5.c b/backend/2of5.c
index 1fd5fc16..1398a20a 100644
--- a/backend/2of5.c
+++ b/backend/2of5.c
@@ -61,7 +61,7 @@ static inline char check_digit(unsigned int count) {
 INTERNAL int matrix_two_of_five(struct zint_symbol *symbol, unsigned char source[], int length) {
 
     int i, error_number;
-    char dest[512]; /* 6 + 80 * 6 + 6 + 1 ~ 512*/
+    char dest[512]; /* 6 + 80 * 6 + 5 + 1 = 492 */
 
     if (length > 80) {
         strcpy(symbol->errtxt, "301: Input too long");
@@ -92,7 +92,7 @@ INTERNAL int matrix_two_of_five(struct zint_symbol *symbol, unsigned char source
 INTERNAL int industrial_two_of_five(struct zint_symbol *symbol, unsigned char source[], int length) {
 
     int i, error_number;
-    char dest[512]; /* 6 + 40 * 10 + 6 + 1 */
+    char dest[512]; /* 6 + 45 * 10 + 5 + 1 = 462 */
 
     if (length > 45) {
         strcpy(symbol->errtxt, "303: Input too long");
@@ -122,7 +122,7 @@ INTERNAL int industrial_two_of_five(struct zint_symbol *symbol, unsigned char so
 /* Code 2 of 5 IATA */
 INTERNAL int iata_two_of_five(struct zint_symbol *symbol, unsigned char source[], int length) {
     int i, error_number;
-    char dest[512]; /* 4 + 45 * 10 + 3 + 1 */
+    char dest[512]; /* 4 + 45 * 10 + 3 + 1 = 458 */
 
     if (length > 45) {
         strcpy(symbol->errtxt, "305: Input too long");
@@ -153,7 +153,7 @@ INTERNAL int iata_two_of_five(struct zint_symbol *symbol, unsigned char source[]
 INTERNAL int logic_two_of_five(struct zint_symbol *symbol, unsigned char source[], int length) {
 
     int i, error_number;
-    char dest[512]; /* 4 + 80 * 6 + 3 + 1 */
+    char dest[512]; /* 4 + 80 * 6 + 3 + 1 = 488 */
 
     if (length > 80) {
         strcpy(symbol->errtxt, "307: Input too long");
@@ -181,17 +181,17 @@ INTERNAL int logic_two_of_five(struct zint_symbol *symbol, unsigned char source[
 }
 
 /* Code 2 of 5 Interleaved */
-INTERNAL int interleaved_two_of_five(struct zint_symbol *symbol, const unsigned char source[], size_t length) {
+INTERNAL int interleaved_two_of_five(struct zint_symbol *symbol, unsigned char source[], int length) {
 
     int i, j, error_number;
-    char bars[7], spaces[7], mixed[14], dest[1000];
+    char bars[7], spaces[7], mixed[14], dest[512]; /* 4 + 90 * 5 + 3 + 1 = 458 */
 #ifndef _MSC_VER
     unsigned char temp[length + 2];
 #else
     unsigned char* temp = (unsigned char *) _alloca((length + 2) * sizeof (unsigned char));
 #endif
 
-    if (length > 89) {
+    if (length > 90) {
         strcpy(symbol->errtxt, "309: Input too long");
         return ZINT_ERROR_TOO_LONG;
     }
@@ -201,24 +201,24 @@ INTERNAL int interleaved_two_of_five(struct zint_symbol *symbol, const unsigned
         return error_number;
     }
 
-    ustrcpy(temp, "");
+    temp[0] = '\0';
     /* Input must be an even number of characters for Interlaced 2 of 5 to work:
        if an odd number of characters has been entered then add a leading zero */
     if (length & 1) {
         ustrcpy(temp, "0");
         length++;
     }
-    ustrcat(temp, source);
+    ustrncat(temp, source, length);
 
     /* start character */
     strcpy(dest, "1111");
 
-    for (i = 0; i < (int) length; i += 2) {
+    for (i = 0; i < length; i += 2) {
         int k = 0;
         /* look up the bars and the spaces and put them in two strings */
-        strcpy(bars, "");
+        bars[0] = '\0';
         lookup(NEON, C25InterTable, temp[i], bars);
-        strcpy(spaces, "");
+        spaces[0] = '\0';
         lookup(NEON, C25InterTable, temp[i + 1], spaces);
 
         /* then merge (interlace) the strings together */
@@ -238,7 +238,6 @@ INTERNAL int interleaved_two_of_five(struct zint_symbol *symbol, const unsigned
     expand(symbol, dest);
     ustrcpy(symbol->text, temp);
     return error_number;
-
 }
 
 /* Interleaved 2-of-5 (ITF) */
@@ -277,7 +276,7 @@ INTERNAL int itf14(struct zint_symbol *symbol, unsigned char source[], int lengt
     }
     localstr[13] = check_digit(count);
     localstr[14] = '\0';
-    error_number = interleaved_two_of_five(symbol, (unsigned char *) localstr, strlen(localstr));
+    error_number = interleaved_two_of_five(symbol, (unsigned char *) localstr, 14);
     ustrcpy(symbol->text, localstr);
 
     if (!((symbol->output_options & BARCODE_BOX) || (symbol->output_options & BARCODE_BIND))) {
@@ -324,7 +323,7 @@ INTERNAL int dpleit(struct zint_symbol *symbol, unsigned char source[], int leng
     }
     localstr[13] = check_digit(count);
     localstr[14] = '\0';
-    error_number = interleaved_two_of_five(symbol, (unsigned char *) localstr, strlen(localstr));
+    error_number = interleaved_two_of_five(symbol, (unsigned char *) localstr, 14);
     ustrcpy(symbol->text, localstr);
     return error_number;
 }
@@ -360,7 +359,7 @@ INTERNAL int dpident(struct zint_symbol *symbol, unsigned char source[], int len
     }
     localstr[11] = check_digit(count);
     localstr[12] = '\0';
-    error_number = interleaved_two_of_five(symbol, (unsigned char *) localstr, strlen(localstr));
+    error_number = interleaved_two_of_five(symbol, (unsigned char *) localstr, 12);
     ustrcpy(symbol->text, localstr);
     return error_number;
 }
diff --git a/backend/auspost.c b/backend/auspost.c
index 5b047fca..3e4a3921 100644
--- a/backend/auspost.c
+++ b/backend/auspost.c
@@ -2,7 +2,7 @@
 
 /*
     libzint - the open source barcode library
-    Copyright (C) 2008-2017 Robin Stuart <rstuart114@gmail.com>
+    Copyright (C) 2008 - 2020 Robin Stuart <rstuart114@gmail.com>
 
     Redistribution and use in source and binary forms, with or without
     modification, are permitted provided that the following conditions
@@ -55,9 +55,7 @@ static const char *AusBarTable[64] = {
     "332", "333"
 };
 
-#include <string.h>
 #include <stdio.h>
-#include <stdlib.h>
 #include "common.h"
 #include "reedsol.h"
 #ifdef _MSC_VER
@@ -103,8 +101,8 @@ INTERNAL int australia_post(struct zint_symbol *symbol, unsigned char source[],
        3 = Tracker only */
     int error_number;
     int writer;
-    unsigned int loopey, reader;
-    size_t h;
+    int loopey, reader;
+    int h;
 
     char data_pattern[200];
     char fcc[3] = {0, 0, 0}, dpid[10];
@@ -168,12 +166,16 @@ INTERNAL int australia_post(struct zint_symbol *symbol, unsigned char source[],
         localstr[zeroes] = '\0';
     }
 
-    strncat(localstr, (char *) source, length);
-    h = strlen(localstr);
+    if (symbol->debug & ZINT_DEBUG_PRINT) {
+        printf("AUSPOST FCC: %s\n", fcc);
+    }
+
+    ustrncat(localstr, source, length);
+    h = (int) strlen(localstr);
     /* Verifiy that the first 8 characters are numbers */
     memcpy(dpid, localstr, 8);
     dpid[8] = '\0';
-    error_number = is_sane(NEON, (unsigned char *) dpid, strlen(dpid));
+    error_number = is_sane(NEON, (unsigned char *) dpid, 8);
     if (error_number == ZINT_ERROR_INVALID_DATA) {
         strcpy(symbol->errtxt, "405: Invalid characters in DPID");
         return error_number;
@@ -187,8 +189,6 @@ INTERNAL int australia_post(struct zint_symbol *symbol, unsigned char source[],
         lookup(NEON, AusNTable, fcc[reader], data_pattern);
     }
 
-    /* printf("AUSPOST FCC: %s  ", fcc); */
-
     /* Delivery Point Identifier (DPID) */
     for (reader = 0; reader < 8; reader++) {
         lookup(NEON, AusNTable, dpid[reader], data_pattern);
@@ -208,7 +208,7 @@ INTERNAL int australia_post(struct zint_symbol *symbol, unsigned char source[],
     }
 
     /* Filler bar */
-    h = strlen(data_pattern);
+    h = (int) strlen(data_pattern);
     switch (h) {
         case 22:
         case 37:
@@ -227,7 +227,7 @@ INTERNAL int australia_post(struct zint_symbol *symbol, unsigned char source[],
 
     /* Turn the symbol into a bar pattern ready for plotting */
     writer = 0;
-    h = strlen(data_pattern);
+    h = (int) strlen(data_pattern);
     for (loopey = 0; loopey < h; loopey++) {
         if ((data_pattern[loopey] == '1') || (data_pattern[loopey] == '0')) {
             set_module(symbol, 0, writer);
diff --git a/backend/aztec.c b/backend/aztec.c
index e3c3acda..a6aa49eb 100644
--- a/backend/aztec.c
+++ b/backend/aztec.c
@@ -100,12 +100,12 @@ static char get_next_mode(char encode_mode[], const int src_len, int i) {
     }
 }
 
-static int az_bin_append_posn(const int arg, const int length, char *binary, int posn) {
+static int az_bin_append_posn(const int arg, const int length, char *binary, int bin_posn) {
 
-    if (posn + length > AZTEC_BIN_CAPACITY) {
+    if (bin_posn + length > AZTEC_BIN_CAPACITY) {
         return 0; /* Fail */
     }
-    return bin_append_posn(arg, length, binary, posn);
+    return bin_append_posn(arg, length, binary, bin_posn);
 }
 
 static int aztec_text_process(const unsigned char source[], int src_len, char binary_string[], const int gs1,
@@ -1470,9 +1470,11 @@ INTERNAL int aztec(struct zint_symbol *symbol, unsigned char source[], int lengt
 
 /* Encodes Aztec runes as specified in ISO/IEC 24778:2008 Annex A */
 INTERNAL int aztec_runes(struct zint_symbol *symbol, unsigned char source[], int length) {
-    int input_value, error_number, i, y, x;
+    unsigned int input_value;
+    int error_number, i, y, x, r;
     char binary_string[28];
     unsigned char data_codewords[3], ecc_codewords[6];
+    int bp = 0;
     int debug = symbol->debug & ZINT_DEBUG_PRINT;
     rs_t rs;
 
@@ -1503,52 +1505,17 @@ INTERNAL int aztec_runes(struct zint_symbol *symbol, unsigned char source[], int
         return ZINT_ERROR_INVALID_DATA;
     }
 
-    *binary_string = '\0';
-    bin_append(input_value, 8, binary_string);
+    bp = bin_append_posn(input_value, 8, binary_string, bp);
 
-    data_codewords[0] = 0;
-    data_codewords[1] = 0;
-
-    for (i = 0; i < 2; i++) {
-        if (binary_string[i * 4] == '1') {
-            data_codewords[i] += 8;
-        }
-        if (binary_string[(i * 4) + 1] == '1') {
-            data_codewords[i] += 4;
-        }
-        if (binary_string[(i * 4) + 2] == '1') {
-            data_codewords[i] += 2;
-        }
-        if (binary_string[(i * 4) + 3] == '1') {
-            data_codewords[i] += 1;
-        }
-    }
+    data_codewords[0] = input_value >> 4;
+    data_codewords[1] = input_value & 0xF;
 
     rs_init_gf(&rs, 0x13);
     rs_init_code(&rs, 5, 1);
     rs_encode(&rs, 2, data_codewords, ecc_codewords);
 
     for (i = 0; i < 5; i++) {
-        if (ecc_codewords[4 - i] & 0x08) {
-            binary_string[(i * 4) + 8] = '1';
-        } else {
-            binary_string[(i * 4) + 8] = '0';
-        }
-        if (ecc_codewords[4 - i] & 0x04) {
-            binary_string[(i * 4) + 9] = '1';
-        } else {
-            binary_string[(i * 4) + 9] = '0';
-        }
-        if (ecc_codewords[4 - i] & 0x02) {
-            binary_string[(i * 4) + 10] = '1';
-        } else {
-            binary_string[(i * 4) + 10] = '0';
-        }
-        if (ecc_codewords[4 - i] & 0x01) {
-            binary_string[(i * 4) + 11] = '1';
-        } else {
-            binary_string[(i * 4) + 11] = '0';
-        }
+        bp = bin_append_posn(ecc_codewords[4 - i], 4, binary_string, bp);
     }
 
     for (i = 0; i < 28; i += 2) {
@@ -1564,12 +1531,13 @@ INTERNAL int aztec_runes(struct zint_symbol *symbol, unsigned char source[], int
     }
 
     for (y = 8; y < 19; y++) {
+        r = y * 27;
         for (x = 8; x < 19; x++) {
-            if (CompactAztecMap[(y * 27) + x] == 1) {
+            if (CompactAztecMap[r + x] == 1) {
                 set_module(symbol, y - 8, x - 8);
             }
-            if (CompactAztecMap[(y * 27) + x] >= 2) {
-                if (binary_string[CompactAztecMap[(y * 27) + x] - 2000] == '1') {
+            if (CompactAztecMap[r + x] >= 2) {
+                if (binary_string[CompactAztecMap[r + x] - 2000] == '1') {
                     set_module(symbol, y - 8, x - 8);
                 }
             }
diff --git a/backend/codablock.c b/backend/codablock.c
index bc869ecc..a2e449cc 100644
--- a/backend/codablock.c
+++ b/backend/codablock.c
@@ -33,7 +33,6 @@
 
 #include <stdio.h>
 #include <math.h>
-#include <string.h>
 #ifdef _MSC_VER
 #include <malloc.h>
 #endif
diff --git a/backend/code.c b/backend/code.c
index ae3d31a0..a4cb413b 100644
--- a/backend/code.c
+++ b/backend/code.c
@@ -213,7 +213,7 @@ INTERNAL int code_11(struct zint_symbol *symbol, unsigned char source[], int len
 }
 
 /* Code 39 */
-INTERNAL int c39(struct zint_symbol *symbol, unsigned char source[], const size_t length) {
+INTERNAL int c39(struct zint_symbol *symbol, unsigned char source[], int length) {
     int i;
     int counter;
     int error_number;
@@ -246,7 +246,7 @@ INTERNAL int c39(struct zint_symbol *symbol, unsigned char source[], const size_
     /* Start character */
     strcpy(dest, "1211212111");
 
-    for (i = 0; i < (int) length; i++) {
+    for (i = 0; i < length; i++) {
         lookup(SILVER, C39Table, source[i], dest);
         counter += posn(SILVER, source[i]);
     }
@@ -297,7 +297,7 @@ INTERNAL int c39(struct zint_symbol *symbol, unsigned char source[], const size_
 
     if ((symbol->symbology == BARCODE_LOGMARS) || (symbol->symbology == BARCODE_HIBC_39)) {
         /* LOGMARS uses wider 'wide' bars than normal Code 39 */
-        counter = strlen(dest);
+        counter = (int) strlen(dest);
         for (i = 0; i < counter; i++) {
             if (dest[i] == '2') {
                 dest[i] = '3';
@@ -309,7 +309,7 @@ INTERNAL int c39(struct zint_symbol *symbol, unsigned char source[], const size_
 
     if (symbol->symbology == BARCODE_CODE39) {
         ustrcpy(symbol->text, "*");
-        ustrcat(symbol->text, source);
+        ustrncat(symbol->text, source, length);
         ustrcat(symbol->text, localstr);
         ustrcat(symbol->text, "*");
     } else {
@@ -359,7 +359,7 @@ INTERNAL int pharmazentral(struct zint_symbol *symbol, unsigned char source[], i
     }
     localstr[8] = itoc(check_digit);
     localstr[9] = '\0';
-    error_number = c39(symbol, (unsigned char *) localstr, strlen(localstr));
+    error_number = c39(symbol, (unsigned char *) localstr, 9);
     ustrcpy(symbol->text, "PZN ");
     ustrcat(symbol->text, localstr);
     return error_number;
@@ -388,7 +388,7 @@ INTERNAL int ec39(struct zint_symbol *symbol, unsigned char source[], int length
     }
 
     /* Then sends the buffer to the C39 function */
-    error_number = c39(symbol, buffer, ustrlen(buffer));
+    error_number = c39(symbol, buffer, (int) ustrlen(buffer));
 
     for (i = 0; i < length; i++)
         symbol->text[i] = source[i] >= ' ' && source[i] != 0x7F ? source[i] : ' ';
@@ -711,19 +711,18 @@ INTERNAL int channel_code(struct zint_symbol *symbol, unsigned char source[], in
 }
 
 /* Vehicle Identification Number (VIN) */
-INTERNAL int vin(struct zint_symbol *symbol, const unsigned char source[], const size_t in_length) {
+INTERNAL int vin(struct zint_symbol *symbol, unsigned char source[], int length) {
 
     /* This code verifies the check digit present in North American VIN codes */
 
     char local_source[18];
-    char dest[200];
+    char dest[200]; /* 10 + 10 + 17 * 10 + 9 + 1 = 200 */
     char input_check;
     char output_check;
     int value[17];
     int weight[17] = {8, 7, 6, 5, 4, 3, 2, 10, 0, 9, 8, 7, 6, 5, 4, 3, 2};
     int sum;
     int i;
-    int length = (int) in_length;
 
     // Check length
     if (length != 17) {
@@ -741,7 +740,6 @@ INTERNAL int vin(struct zint_symbol *symbol, const unsigned char source[], const
 
     to_upper((unsigned char *) local_source);
 
-
     // Check digit only valid for North America
     if (local_source[0] >= '1' && local_source[0] <= '5') {
         input_check = local_source[8];
diff --git a/backend/code1.c b/backend/code1.c
index f6baa28e..c3e09b54 100644
--- a/backend/code1.c
+++ b/backend/code1.c
@@ -151,27 +151,27 @@ static int c1_look_ahead_test(unsigned char source[], int sourcelen, int positio
 
     /* Step J */
     if (current_mode == C1_ASCII) {
-        ascii_count = 0.0;
-        c40_count = 1.0;
-        text_count = 1.0;
-        edi_count = 1.0;
-        byte_count = 2.0;
+        ascii_count = 0.0f;
+        c40_count = 1.0f;
+        text_count = 1.0f;
+        edi_count = 1.0f;
+        byte_count = 2.0f;
     } else {
-        ascii_count = 1.0;
-        c40_count = 2.0;
-        text_count = 2.0;
-        edi_count = 2.0;
-        byte_count = 3.0;
+        ascii_count = 1.0f;
+        c40_count = 2.0f;
+        text_count = 2.0f;
+        edi_count = 2.0f;
+        byte_count = 3.0f;
     }
 
     switch (current_mode) {
-        case C1_C40: c40_count = 0.0;
+        case C1_C40: c40_count = 0.0f;
             break;
-        case C1_TEXT: text_count = 0.0;
+        case C1_TEXT: text_count = 0.0f;
             break;
-        case C1_BYTE: byte_count = 0.0;
+        case C1_BYTE: byte_count = 0.0f;
             break;
-        case C1_EDI: edi_count = 0.0;
+        case C1_EDI: edi_count = 0.0f;
             break;
     }
 
@@ -185,106 +185,106 @@ static int c1_look_ahead_test(unsigned char source[], int sourcelen, int positio
 
         /* Step L */
         if ((source[sp] >= '0') && (source[sp] <= '9')) {
-            ascii_count += 0.5;
+            ascii_count += 0.5f;
         } else {
-            ascii_count = ceil(ascii_count);
+            ascii_count = (float) ceil(ascii_count);
             if (source[sp] > 127) {
-                ascii_count += 2.0;
+                ascii_count += 2.0f;
             } else {
-                ascii_count += 1.0;
+                ascii_count += 1.0f;
             }
         }
 
         /* Step M */
         done = 0;
         if (reduced_char == ' ') {
-            c40_count += (2.0 / 3.0);
+            c40_count += (2.0f / 3.0f);
             done = 1;
         }
         if ((reduced_char >= '0') && (reduced_char <= '9')) {
-            c40_count += (2.0 / 3.0);
+            c40_count += (2.0f / 3.0f);
             done = 1;
         }
         if ((reduced_char >= 'A') && (reduced_char <= 'Z')) {
-            c40_count += (2.0 / 3.0);
+            c40_count += (2.0f / 3.0f);
             done = 1;
         }
         if (source[sp] > 127) {
-            c40_count += (4.0 / 3.0);
+            c40_count += (4.0f / 3.0f);
         }
         if (done == 0) {
-            c40_count += (4.0 / 3.0);
+            c40_count += (4.0f / 3.0f);
         }
 
         /* Step N */
         done = 0;
         if (reduced_char == ' ') {
-            text_count += (2.0 / 3.0);
+            text_count += (2.0f / 3.0f);
             done = 1;
         }
         if ((reduced_char >= '0') && (reduced_char <= '9')) {
-            text_count += (2.0 / 3.0);
+            text_count += (2.0f / 3.0f);
             done = 1;
         }
         if ((reduced_char >= 'a') && (reduced_char <= 'z')) {
-            text_count += (2.0 / 3.0);
+            text_count += (2.0f / 3.0f);
             done = 1;
         }
         if (source[sp] > 127) {
-            text_count += (4.0 / 3.0);
+            text_count += (4.0f / 3.0f);
         }
         if (done == 0) {
-            text_count += (4.0 / 3.0);
+            text_count += (4.0f / 3.0f);
         }
 
         /* Step O */
         done = 0;
         if (source[sp] == 13) {
-            edi_count += (2.0 / 3.0);
+            edi_count += (2.0f / 3.0f);
             done = 1;
         }
         if (source[sp] == '*') {
-            edi_count += (2.0 / 3.0);
+            edi_count += (2.0f / 3.0f);
             done = 1;
         }
         if (source[sp] == '>') {
-            edi_count += (2.0 / 3.0);
+            edi_count += (2.0f / 3.0f);
             done = 1;
         }
         if (source[sp] == ' ') {
-            edi_count += (2.0 / 3.0);
+            edi_count += (2.0f / 3.0f);
             done = 1;
         }
         if ((source[sp] >= '0') && (source[sp] <= '9')) {
-            edi_count += (2.0 / 3.0);
+            edi_count += (2.0f / 3.0f);
             done = 1;
         }
         if ((source[sp] >= 'A') && (source[sp] <= 'Z')) {
-            edi_count += (2.0 / 3.0);
+            edi_count += (2.0f / 3.0f);
             done = 1;
         }
         if (source[sp] > 127) {
-            edi_count += (13.0 / 3.0);
+            edi_count += (13.0f / 3.0f);
         } else {
             if (done == 0) {
-                edi_count += (10.0 / 3.0);
+                edi_count += (10.0f / 3.0f);
             }
         }
 
         /* Step P */
         if (gs1 && (source[sp] == '[')) {
-            byte_count += 3.0;
+            byte_count += 3.0f;
         } else {
-            byte_count += 1.0;
+            byte_count += 1.0f;
         }
 
     }
 
-    ascii_count = ceil(ascii_count);
-    c40_count = ceil(c40_count);
-    text_count = ceil(text_count);
-    edi_count = ceil(edi_count);
-    byte_count = ceil(byte_count);
+    ascii_count = (float) ceil(ascii_count);
+    c40_count = (float) ceil(c40_count);
+    text_count = (float) ceil(text_count);
+    edi_count = (float) ceil(edi_count);
+    byte_count = (float) ceil(byte_count);
     best_scheme = C1_ASCII;
 
     if (sp == sourcelen) {
@@ -313,12 +313,12 @@ static int c1_look_ahead_test(unsigned char source[], int sourcelen, int positio
     } else {
         /* Step Q */
 
-        if (((edi_count + 1.0 <= ascii_count) && (edi_count + 1.0 <= c40_count)) &&
-                ((edi_count + 1.0 <= byte_count) && (edi_count + 1.0 <= text_count))) {
+        if (((edi_count + 1.0f <= ascii_count) && (edi_count + 1.0f <= c40_count)) &&
+                ((edi_count + 1.0f <= byte_count) && (edi_count + 1.0f <= text_count))) {
             best_scheme = C1_EDI;
         }
 
-        if ((c40_count + 1.0 <= ascii_count) && (c40_count + 1.0 <= text_count)) {
+        if ((c40_count + 1.0f <= ascii_count) && (c40_count + 1.0f <= text_count)) {
 
             if (c40_count < edi_count) {
                 best_scheme = C1_C40;
@@ -333,18 +333,18 @@ static int c1_look_ahead_test(unsigned char source[], int sourcelen, int positio
             }
         }
 
-        if (((text_count + 1.0 <= ascii_count) && (text_count + 1.0 <= c40_count)) &&
-                ((text_count + 1.0 <= byte_count) && (text_count + 1.0 <= edi_count))) {
+        if (((text_count + 1.0f <= ascii_count) && (text_count + 1.0f <= c40_count)) &&
+                ((text_count + 1.0f <= byte_count) && (text_count + 1.0f <= edi_count))) {
             best_scheme = C1_TEXT;
         }
 
-        if (((ascii_count + 1.0 <= byte_count) && (ascii_count + 1.0 <= c40_count)) &&
-                ((ascii_count + 1.0 <= text_count) && (ascii_count + 1.0 <= edi_count))) {
+        if (((ascii_count + 1.0f <= byte_count) && (ascii_count + 1.0f <= c40_count)) &&
+                ((ascii_count + 1.0f <= text_count) && (ascii_count + 1.0f <= edi_count))) {
             best_scheme = C1_ASCII;
         }
 
-        if (((byte_count + 1.0 <= ascii_count) && (byte_count + 1.0 <= c40_count)) &&
-                ((byte_count + 1.0 <= text_count) && (byte_count + 1.0 <= edi_count))) {
+        if (((byte_count + 1.0f <= ascii_count) && (byte_count + 1.0f <= c40_count)) &&
+                ((byte_count + 1.0f <= text_count) && (byte_count + 1.0f <= edi_count))) {
             best_scheme = C1_BYTE;
         }
     }
diff --git a/backend/code16k.c b/backend/code16k.c
index a0e4ff04..1d5ba90c 100644
--- a/backend/code16k.c
+++ b/backend/code16k.c
@@ -35,7 +35,6 @@
 
 /* Code 16k can hold up to 77 characters or 154 numbers */
 
-#include <string.h>
 #include <stdio.h>
 #include <assert.h>
 #include "common.h"
@@ -107,7 +106,7 @@ static void c16k_set_c(const unsigned char source_a, unsigned char source_b, int
     (*bar_chars)++;
 }
 
-INTERNAL int code16k(struct zint_symbol *symbol, unsigned char source[], const size_t length) {
+INTERNAL int code16k(struct zint_symbol *symbol, unsigned char source[], int length) {
     char width_pattern[100];
     int current_row, rows, looper, first_check, second_check;
     int indexchaine;
@@ -242,35 +241,35 @@ INTERNAL int code16k(struct zint_symbol *symbol, unsigned char source[], const s
 
     /* Make sure the data will fit in the symbol */
     last_set = set[0];
-    glyph_count = 0.0;
+    glyph_count = 0.0f;
     for (i = 0; i < input_length; i++) {
         if ((set[i] == 'a') || (set[i] == 'b')) {
-            glyph_count = glyph_count + 1.0;
+            glyph_count = glyph_count + 1.0f;
         }
         if (fset[i] == 'f') {
-            glyph_count = glyph_count + 1.0;
+            glyph_count = glyph_count + 1.0f;
         }
         if (((set[i] == 'A') || (set[i] == 'B')) || (set[i] == 'C')) {
             if (set[i] != last_set) {
                 last_set = set[i];
-                glyph_count = glyph_count + 1.0;
+                glyph_count = glyph_count + 1.0f;
             }
         }
         if (i == 0) {
             if ((set[i] == 'B') && (set[1] == 'C')) {
-                glyph_count = glyph_count - 1.0;
+                glyph_count = glyph_count - 1.0f;
             }
             if ((set[i] == 'B') && (set[1] == 'B')) {
                 if (set[2] == 'C') {
-                    glyph_count = glyph_count - 1.0;
+                    glyph_count = glyph_count - 1.0f;
                 }
             }
         }
 
         if ((set[i] == 'C') && (!((gs1) && (source[i] == '[')))) {
-            glyph_count = glyph_count + 0.5;
+            glyph_count = glyph_count + 0.5f;
         } else {
-            glyph_count = glyph_count + 1.0;
+            glyph_count = glyph_count + 1.0f;
         }
     }
 
@@ -279,13 +278,13 @@ INTERNAL int code16k(struct zint_symbol *symbol, unsigned char source[], const s
         glyph_count--;
     }
 
-    if (glyph_count > 77.0) {
+    if (glyph_count > 77.0f) {
         strcpy(symbol->errtxt, "421: Input too long");
         return ZINT_ERROR_TOO_LONG;
     }
 
     /* Calculate how tall the symbol will be */
-    glyph_count = glyph_count + 2.0;
+    glyph_count = glyph_count + 2.0f;
     i = (int)glyph_count;
     rows = (i / 5);
     if (i % 5 > 0) {
@@ -473,7 +472,7 @@ INTERNAL int code16k(struct zint_symbol *symbol, unsigned char source[], const s
         /* Write the information into the symbol */
         writer = 0;
         flip_flop = 1;
-        for (mx_reader = 0, len = strlen(width_pattern); mx_reader < len; mx_reader++) {
+        for (mx_reader = 0, len = (int) strlen(width_pattern); mx_reader < len; mx_reader++) {
             for (looper = 0; looper < ctoi(width_pattern[mx_reader]); looper++) {
                 if (flip_flop == 1) {
                     set_module(symbol, current_row, writer);
diff --git a/backend/code49.c b/backend/code49.c
index 3d7aebff..52a96f0f 100644
--- a/backend/code49.c
+++ b/backend/code49.c
@@ -31,7 +31,6 @@
  */
 /* vim: set ts=4 sw=4 et : */
 
-#include <string.h>
 #include <stdio.h>
 #include "common.h"
 #include "code49.h"
@@ -40,7 +39,7 @@
 
 /* "!" represents Shift 1 and "&" represents Shift 2, "*" represents FNC1 */
 
-INTERNAL int code_49(struct zint_symbol *symbol, unsigned char source[], const int length) {
+INTERNAL int code_49(struct zint_symbol *symbol, unsigned char source[], int length) {
     int i, j, rows, M, x_count, y_count, z_count, posn_val, local_value;
     char intermediate[170] = "";
     int codewords[170], codeword_count;
diff --git a/backend/dmatrix.c b/backend/dmatrix.c
index a7b86875..eb877114 100644
--- a/backend/dmatrix.c
+++ b/backend/dmatrix.c
@@ -46,7 +46,7 @@
 #include <malloc.h>
 /* ceilf (C99) not before MSVC++2013 (C++ 12.0) */
 #if _MSC_VER < 1800
-#define ceilf ceil
+#define ceilf (float) ceil
 #endif
 #endif
 #include "common.h"
@@ -241,35 +241,35 @@ static int isX12(const int source) {
     return 0;
 }
 
-/* Insert a character into the middle of a string at position posn */
-static void dminsert(char binary_string[], const int posn, const char newbit) {
+/* Insert a character into the middle of a string at position bin_posn */
+static void dminsert(char binary_string[], const int bin_posn, const char newbit) {
     int i, end;
 
     end = (int) strlen(binary_string);
-    for (i = end + 1; i > posn; i--) {
+    for (i = end + 1; i > bin_posn; i--) {
         binary_string[i] = binary_string[i - 1];
     }
-    binary_string[posn] = newbit;
+    binary_string[bin_posn] = newbit;
 }
 
-static void insert_value(unsigned char binary_stream[], const int posn, const int streamlen, const int newbit) {
+static void insert_value(unsigned char binary_stream[], const int bin_posn, const int streamlen, const int newbit) {
     int i;
 
-    for(i = (int)streamlen; i > posn; i--) {
+    for (i = streamlen; i > bin_posn; i--) {
         binary_stream[i] = binary_stream[i - 1];
     }
-    binary_stream[posn] = (unsigned char) newbit;
+    binary_stream[bin_posn] = (unsigned char) newbit;
 }
 
-static int p_r_6_2_1(const unsigned char inputData[], const size_t position, const size_t sourcelen) {
+static int p_r_6_2_1(const unsigned char inputData[], const int position, const int sourcelen) {
     /* Annex P section (r)(6)(ii)(I)
        "If one of the three X12 terminator/separator characters first
         occurs in the yet to be processed data before a non-X12 character..."
      */
 
-    size_t i;
-    size_t nonX12Position = 0;
-    size_t specialX12Position = 0;
+    int i;
+    int nonX12Position = 0;
+    int specialX12Position = 0;
     int retval = 0;
 
     for (i = position; i < sourcelen; i++) {
@@ -298,11 +298,12 @@ static int p_r_6_2_1(const unsigned char inputData[], const size_t position, con
 }
 
 /* 'look ahead test' from Annex P */
-static int look_ahead_test(const unsigned char inputData[], const size_t sourcelen, const size_t position, const int current_mode, const int gs1) {
+static int look_ahead_test(const unsigned char inputData[], const int sourcelen, const int position,
+            const int current_mode, const int gs1) {
     float ascii_count, c40_count, text_count, x12_count, edf_count, b256_count, best_count;
     const float stiction = (1.0F / 24.0F); // smallest change to act on, to get around floating point inaccuracies
     int    best_scheme;
-    size_t sp;
+    int sp;
 
     best_scheme = DM_NULL;
 
@@ -528,12 +529,12 @@ static int look_ahead_test(const unsigned char inputData[], const size_t sourcel
 /* Encodes data using ASCII, C40, Text, X12, EDIFACT or Base 256 modes as appropriate
    Supports encoding FNC1 in supporting systems */
 static int dm200encode(struct zint_symbol *symbol, const unsigned char source[], unsigned char target[],
-        int *last_mode, int *last_shift, size_t *length_p, int process_buffer[], int *process_p, int *binlen_p) {
+        int *last_mode, int *last_shift, int *length_p, int process_buffer[], int *process_p, int *binlen_p) {
 
-    size_t sp;
+    int sp;
     int tp, i, gs1;
     int current_mode, next_mode;
-    size_t inputlen = *length_p;
+    int inputlen = *length_p;
     int debug = symbol->debug & ZINT_DEBUG_PRINT;
 #ifndef _MSC_VER
     char binary[2 * inputlen + 1 + 4 + 1]; /* Allow for GS1/READER_INIT, ECI and nul chars overhead */
@@ -589,15 +590,13 @@ static int dm200encode(struct zint_symbol *symbol, const unsigned char source[],
             target[tp] = (unsigned char) symbol->eci + 1;
             tp++;
             strcat(binary, "  ");
-        }
-        if ((symbol->eci >= 127) && (symbol->eci <= 16382)) {
+        } else if (symbol->eci <= 16382) {
             target[tp] = (unsigned char) ((symbol->eci - 127) / 254) + 128;
             tp++;
             target[tp] = (unsigned char) ((symbol->eci - 127) % 254) + 1;
             tp++;
             strcat(binary, "   ");
-        }
-        if (symbol->eci >= 16383) {
+        } else {
             target[tp] = (unsigned char) ((symbol->eci - 16383) / 64516) + 192;
             tp++;
             target[tp] = (unsigned char) (((symbol->eci - 16383) / 254) % 254) + 1;
@@ -760,12 +759,12 @@ static int dm200encode(struct zint_symbol *symbol, const unsigned char source[],
                 (*process_p)++;
 
                 while (*process_p >= 3) {
-                    int iv;
+                    unsigned int iv;
 
                     iv = (1600 * process_buffer[0]) + (40 * process_buffer[1]) + (process_buffer[2]) + 1;
-                    target[tp] = (unsigned char) (iv / 256);
+                    target[tp] = (unsigned char) (iv >> 8);
                     tp++;
-                    target[tp] = iv % 256;
+                    target[tp] = (unsigned char) (iv & 0xFF);
                     tp++;
                     strcat(binary, "  ");
                     if (debug) printf("[%d %d %d] ", process_buffer[0], process_buffer[1], process_buffer[2]);
@@ -831,12 +830,12 @@ static int dm200encode(struct zint_symbol *symbol, const unsigned char source[],
                 (*process_p)++;
 
                 while (*process_p >= 3) {
-                    int iv;
+                    unsigned int iv;
 
                     iv = (1600 * process_buffer[0]) + (40 * process_buffer[1]) + (process_buffer[2]) + 1;
-                    target[tp] = (unsigned char) (iv / 256);
+                    target[tp] = (unsigned char) (iv >> 8);
                     tp++;
-                    target[tp] = iv % 256;
+                    target[tp] = (unsigned char) (iv & 0xFF);
                     tp++;
                     strcat(binary, "  ");
                     if (debug) printf("[%d %d %d] ", process_buffer[0], process_buffer[1], process_buffer[2]);
@@ -887,12 +886,12 @@ static int dm200encode(struct zint_symbol *symbol, const unsigned char source[],
                 (*process_p)++;
 
                 while (*process_p >= 3) {
-                    int iv;
+                    unsigned int iv;
 
                     iv = (1600 * process_buffer[0]) + (40 * process_buffer[1]) + (process_buffer[2]) + 1;
-                    target[tp] = (unsigned char) (iv / 256);
+                    target[tp] = (unsigned char) (iv >> 8);
                     tp++;
-                    target[tp] = iv % 256;
+                    target[tp] = (unsigned char) (iv & 0xFF);
                     tp++;
                     strcat(binary, "  ");
                     if (debug) printf("[%d %d %d] ", process_buffer[0], process_buffer[1], process_buffer[2]);
@@ -941,7 +940,10 @@ static int dm200encode(struct zint_symbol *symbol, const unsigned char source[],
                 target[tp] = (unsigned char) (((process_buffer[2] & 0x03) << 6) + process_buffer[3]);
                 tp++;
                 strcat(binary, "   ");
-                if (debug) printf("[%d %d %d %d] ", process_buffer[0], process_buffer[1], process_buffer[2], process_buffer[3]);
+                if (debug) {
+                    printf("[%d %d %d %d] ", process_buffer[0], process_buffer[1], process_buffer[2],
+                        process_buffer[3]);
+                }
 
                 process_buffer[0] = process_buffer[4];
                 process_buffer[1] = process_buffer[5];
@@ -1026,21 +1028,27 @@ static int dm200encode(struct zint_symbol *symbol, const unsigned char source[],
     return 0;
 }
 
-static int dm200encode_remainder(unsigned char target[], int target_length, const unsigned char source[], const size_t inputlen,
-        const int last_mode, const int last_shift, const int process_buffer[], const int process_p, const int symbols_left, int debug) {
+static int dm200encode_remainder(unsigned char target[], int target_length, const unsigned char source[],
+            const int inputlen, const int last_mode, const int last_shift, const int process_buffer[],
+            const int process_p, const int symbols_left, int debug) {
 
     switch (last_mode) {
         case DM_C40:
         case DM_TEXT:
-            /* NOTE: the use of a 0-padded doublet is only mentioned in ISO/IEC 16022:2006 for case 5.2.5.2 (b) when 2 symbols and
-             * 2 C40/Text characters are left, but using it here also for other cases. This matches the behaviour of tec-it (but
-             * not BWIPP) and is used for figures 4.15-1-1 and 4.15-1-1 in GS1 General Specifications. */
-
-            if (debug) printf("%s last_shift %d, symbols_left %d, process_p %d ", last_mode == DM_C40 ? "C40" : "TEX", last_shift, symbols_left, process_p);
+            /* NOTE: the use of a 0-padded doublet is only mentioned in ISO/IEC 16022:2006 for case 5.2.5.2 (b)
+             * when 2 symbols and 2 C40/Text characters are left, but using it here also for other cases. This
+             * matches the behaviour of tec-it (but not BWIPP) and is used for figures 4.15-1-1 and 4.15-1-1 in
+             * GS1 General Specifications.
+             */
+            if (debug) {
+                printf("%s last_shift %d, symbols_left %d, process_p %d ", last_mode == DM_C40 ? "C40" : "TEX",
+                    last_shift, symbols_left, process_p);
+            }
             if (process_p == 1) // 1 data character left to encode.
             {
                 if (last_shift) {
-                    target[target_length - 1] -= last_shift - 1; // Remove shift from second half of previous doublet leaving pad value (0)
+                    // Remove shift from second half of previous doublet leaving pad value (0)
+                    target[target_length - 1] -= last_shift - 1;
                 }
                 if (symbols_left > 1) {
                     target[target_length] = 254;
@@ -1053,10 +1061,10 @@ static int dm200encode_remainder(unsigned char target[], int target_length, cons
             } else if (process_p == 2) // 2 data characters left to encode.
             {
                 // Pad with shift 1 value (0) and encode as double.
-                int intValue = (1600 * process_buffer[0]) + (40 * process_buffer[1]) + 1; // ie (0 + 1).
-                target[target_length] = (unsigned char) (intValue / 256);
+                unsigned int intValue = (1600 * process_buffer[0]) + (40 * process_buffer[1]) + 1; // ie (0 + 1).
+                target[target_length] = (unsigned char) (intValue >> 8);
                 target_length++;
-                target[target_length] = (unsigned char) (intValue % 256);
+                target[target_length] = (unsigned char) (intValue & 0xFF);
                 target_length++;
                 if (debug) printf("[%d %d %d] ", process_buffer[0], process_buffer[1], 0);
                 if (symbols_left > 2) {
@@ -1129,7 +1137,8 @@ static int dm200encode_remainder(unsigned char target[], int target_length, cons
                     target_length++;
                     if (debug) printf("[%d 31 0 0] ", process_buffer[0]);
                 } else if (process_p == 2) {
-                    target[target_length] = (unsigned char) ((process_buffer[0] << 2) + ((process_buffer[1] & 0x30) >> 4));
+                    target[target_length] = (unsigned char) ((process_buffer[0] << 2)
+                                            + ((process_buffer[1] & 0x30) >> 4));
                     target_length++;
                     target[target_length] = (unsigned char) (((process_buffer[1] & 0x0f) << 4) + ((31 & 0x3c) >> 2));
                     target_length++;
@@ -1137,9 +1146,11 @@ static int dm200encode_remainder(unsigned char target[], int target_length, cons
                     target_length++;
                     if (debug) printf("[%d %d 31 0] ", process_buffer[0], process_buffer[1]);
                 } else if (process_p == 3) {
-                    target[target_length] = (unsigned char) ((process_buffer[0] << 2) + ((process_buffer[1] & 0x30) >> 4));
+                    target[target_length] = (unsigned char) ((process_buffer[0] << 2)
+                                            + ((process_buffer[1] & 0x30) >> 4));
                     target_length++;
-                    target[target_length] = (unsigned char) (((process_buffer[1] & 0x0f) << 4) + ((process_buffer[2] & 0x3c) >> 2));
+                    target[target_length] = (unsigned char) (((process_buffer[1] & 0x0f) << 4)
+                                            + ((process_buffer[2] & 0x3c) >> 2));
                     target_length++;
                     target[target_length] = (unsigned char) (((process_buffer[2] & 0x03) << 6) + 31);
                     target_length++;
@@ -1183,9 +1194,8 @@ static void add_tail(unsigned char target[], int tp, const int tail_length) {
     }
 }
 
-static int data_matrix_200(struct zint_symbol *symbol,const unsigned char source[], const size_t in_length) {
+static int data_matrix_200(struct zint_symbol *symbol, const unsigned char source[], int inputlen) {
     int i, skew = 0;
-    size_t inputlen = in_length;
     unsigned char binary[2200];
     int binlen;
     int process_buffer[8]; /* holds remaining data to finalised */
@@ -1199,7 +1209,8 @@ static int data_matrix_200(struct zint_symbol *symbol,const unsigned char source
     int debug = symbol->debug & ZINT_DEBUG_PRINT;
 
     /* inputlen may be decremented by 2 if macro character is used */
-    error_number = dm200encode(symbol, source, binary, &last_mode, &last_shift, &inputlen, process_buffer, &process_p, &binlen);
+    error_number = dm200encode(symbol, source, binary, &last_mode, &last_shift, &inputlen, process_buffer,
+                    &process_p, &binlen);
     if (error_number != 0) {
         return error_number;
     }
@@ -1245,7 +1256,8 @@ static int data_matrix_200(struct zint_symbol *symbol,const unsigned char source
 
     // Now we know the symbol size we can handle the remaining data in the process buffer.
     symbols_left = matrixbytes[symbolsize] - binlen;
-    binlen = dm200encode_remainder(binary, binlen, source, inputlen, last_mode, last_shift, process_buffer, process_p, symbols_left, debug);
+    binlen = dm200encode_remainder(binary, binlen, source, inputlen, last_mode, last_shift, process_buffer,
+                process_p, symbols_left, debug);
 
     if (binlen > matrixbytes[symbolsize]) {
         strcpy(symbol->errtxt, "523: Data too long to fit in symbol");
@@ -1283,7 +1295,9 @@ static int data_matrix_200(struct zint_symbol *symbol,const unsigned char source
     }
 
 #ifdef ZINT_TEST
-    if (symbol->debug & ZINT_DEBUG_TEST) debug_test_codeword_dump(symbol, binary, skew ? 1558 + 620 : bytes + rsblock * (bytes / datablock));
+    if (symbol->debug & ZINT_DEBUG_TEST) {
+        debug_test_codeword_dump(symbol, binary, skew ? 1558 + 620 : bytes + rsblock * (bytes / datablock));
+    }
 #endif
     { // placement
         int x, y, NC, NR, *places;
@@ -1322,11 +1336,9 @@ static int data_matrix_200(struct zint_symbol *symbol,const unsigned char source
         for (y = 0; y < NR; y++) {
             for (x = 0; x < NC; x++) {
                 int v = places[(NR - y - 1) * NC + x];
-                //fprintf (stderr, "%4d", v);
                 if (v == 1 || (v > 7 && (binary[(v >> 3) - 1] & (1 << (v & 7)))))
                     grid[(1 + y + 2 * (y / (FH - 2))) * W + 1 + x + 2 * (x / (FW - 2))] = 1;
             }
-            //fprintf (stderr, "\n");
         }
         for (y = H - 1; y >= 0; y--) {
             for (x = 0; x < W; x++) {
@@ -1346,12 +1358,12 @@ static int data_matrix_200(struct zint_symbol *symbol,const unsigned char source
     return error_number;
 }
 
-INTERNAL int dmatrix(struct zint_symbol *symbol, const unsigned char source[], const size_t in_length) {
+INTERNAL int dmatrix(struct zint_symbol *symbol, unsigned char source[], int length) {
     int error_number;
 
     if (symbol->option_1 <= 1) {
         /* ECC 200 */
-        error_number = data_matrix_200(symbol, source, in_length);
+        error_number = data_matrix_200(symbol, source, length);
     } else {
         /* ECC 000 - 140 */
         strcpy(symbol->errtxt, "524: Older Data Matrix standards are no longer supported");
diff --git a/backend/dotcode.c b/backend/dotcode.c
index 1a017071..7284c432 100644
--- a/backend/dotcode.c
+++ b/backend/dotcode.c
@@ -996,7 +996,7 @@ static int dotcode_encode_message(struct zint_symbol *symbol, const unsigned cha
             if (n >= 2) {
                 /* Empty binary buffer */
                 for (i = 0; i < (binary_buffer_size + 1); i++) {
-                    lawrencium[i] = binary_buffer % 103;
+                    lawrencium[i] = (int) (binary_buffer % 103);
                     binary_buffer /= 103;
                 }
 
@@ -1043,7 +1043,7 @@ static int dotcode_encode_message(struct zint_symbol *symbol, const unsigned cha
 
                 if (binary_buffer_size == 5) {
                     for (i = 0; i < 6; i++) {
-                        lawrencium[i] = binary_buffer % 103;
+                        lawrencium[i] = (int) (binary_buffer % 103);
                         binary_buffer /= 103;
                     }
 
@@ -1066,7 +1066,7 @@ static int dotcode_encode_message(struct zint_symbol *symbol, const unsigned cha
         if ((!done) && (encoding_mode == 'X')) {
             /* Empty binary buffer */
             for (i = 0; i < (binary_buffer_size + 1); i++) {
-                lawrencium[i] = binary_buffer % 103;
+                lawrencium[i] = (int) (binary_buffer % 103);
                 binary_buffer /= 103;
             }
 
@@ -1096,7 +1096,7 @@ static int dotcode_encode_message(struct zint_symbol *symbol, const unsigned cha
         if (binary_buffer_size != 0) {
             /* Empty binary buffer */
             for (i = 0; i < (binary_buffer_size + 1); i++) {
-                lawrencium[i] = binary_buffer % 103;
+                lawrencium[i] = (int) (binary_buffer % 103);
                 binary_buffer /= 103;
             }
 
@@ -1116,20 +1116,21 @@ static int dotcode_encode_message(struct zint_symbol *symbol, const unsigned cha
 }
 
 /* Convert codewords to binary data stream */
-static size_t make_dotstream(unsigned char masked_array[], int array_length, char dot_stream[]) {
+static int make_dotstream(const unsigned char masked_array[], const int array_length, char dot_stream[]) {
     int i;
-
-    dot_stream[0] = '\0';
+    int bp = 0;
 
     /* Mask value is encoded as two dots */
-    bin_append(masked_array[0], 2, dot_stream);
+    bp = bin_append_posn(masked_array[0], 2, dot_stream, bp);
 
     /* The rest of the data uses 9-bit dot patterns from Annex C */
     for (i = 1; i < array_length; i++) {
-        bin_append(dot_patterns[masked_array[i]], 9, dot_stream);
+        bp = bin_append_posn(dot_patterns[masked_array[i]], 9, dot_stream, bp);
     }
 
-    return strlen(dot_stream);
+    dot_stream[bp] = '\0';
+
+    return bp;
 }
 
 /* Determines if a given dot is a reserved corner dot
@@ -1299,14 +1300,14 @@ static void force_corners(int width, int height, char *dot_array) {
     }
 }
 
-INTERNAL int dotcode(struct zint_symbol *symbol, const unsigned char source[], int length) {
+INTERNAL int dotcode(struct zint_symbol *symbol, unsigned char source[], int length) {
     int i, j, k;
-    size_t jc, n_dots;
+    int jc, n_dots;
     int data_length, ecc_length;
     int min_dots, min_area;
     int height, width;
     int mask_score[8];
-    size_t dot_stream_length;
+    int dot_stream_length;
     int high_score, best_mask;
     int binary_finish = 0;
     int debug = symbol->debug;
@@ -1364,7 +1365,7 @@ INTERNAL int dotcode(struct zint_symbol *symbol, const unsigned char source[], i
         height = (int) h;
         width = (int) w;
 
-        if ((width + height) % 2 == 1) {
+        if (((width + height) & 1) == 1) {
             if ((width * height) < min_area) {
                 width++;
                 height++;
diff --git a/backend/emf.c b/backend/emf.c
index 712fa241..43847c66 100644
--- a/backend/emf.c
+++ b/backend/emf.c
@@ -81,19 +81,21 @@ static int count_hexagons(struct zint_symbol *symbol) {
     return hexagons;
 }
 
-static int count_strings(struct zint_symbol *symbol, int *fsize, int *fsize2, int *halign, int *halign1, int *halign2) {
+static int count_strings(struct zint_symbol *symbol, float *fsize, float *fsize2, int *halign, int *halign1,
+            int *halign2) {
     int strings = 0;
     struct zint_vector_string *str;
 
-    *fsize = *fsize2 = *halign = *halign1 = *halign2 = 0;
+    *fsize = *fsize2 = 0.0f;
+    *halign = *halign1 = *halign2 = 0;
 
     str = symbol->vector->strings;
     while (str) {
         /* Allow 2 font sizes */
-        if (*fsize == 0) {
-            *fsize = (int) str->fsize;
-        } else if (str->fsize != *fsize && *fsize2 == 0) {
-            *fsize2 = (int) str->fsize;
+        if (*fsize == 0.0f) {
+            *fsize = str->fsize;
+        } else if (str->fsize != *fsize && *fsize2 == 0.0f) {
+            *fsize2 = str->fsize;
         }
         /* Only 3 haligns possible */
         if (str->halign) {
@@ -136,7 +138,7 @@ static void utfle_copy(unsigned char *output, unsigned char *input, int length)
 
 static int bump_up(int input) {
     /* Strings length must be a multiple of 4 bytes */
-    if ((input % 2) == 1) {
+    if ((input & 1) == 1) {
         input++;
     }
     return input;
@@ -199,10 +201,10 @@ INTERNAL int emf_plot(struct zint_symbol *symbol, int rotate_angle) {
     emr_rectangle_t background;
     emr_settextcolor_t emr_settextcolor;
 
-    int fsize;
+    float fsize;
     emr_extcreatefontindirectw_t emr_extcreatefontindirectw;
     emr_selectobject_t emr_selectobject_font;
-    int fsize2;
+    float fsize2;
     emr_extcreatefontindirectw_t emr_extcreatefontindirectw2;
     emr_selectobject_t emr_selectobject_font2;
     int halign;
@@ -212,7 +214,7 @@ INTERNAL int emf_plot(struct zint_symbol *symbol, int rotate_angle) {
     int halign2;
     emr_settextalign_t emr_settextalign2;
 
-    int current_fsize;
+    float current_fsize;
     int current_halign;
 
 #ifdef _MSC_VER
@@ -220,7 +222,7 @@ INTERNAL int emf_plot(struct zint_symbol *symbol, int rotate_angle) {
     emr_ellipse_t *circle;
     emr_polygon_t *hexagon;
     emr_exttextoutw_t *text;
-    int *text_fsizes;
+    float *text_fsizes;
     int *text_haligns;
 #endif
 
@@ -243,18 +245,19 @@ INTERNAL int emf_plot(struct zint_symbol *symbol, int rotate_angle) {
     string_count = count_strings(symbol, &fsize, &fsize2, &halign, &halign1, &halign2);
 
 #ifndef _MSC_VER
-    emr_rectangle_t rectangle[rectangle_count ? rectangle_count : 1]; // Avoid sanitize runtime error by making always non-zero
+    // Avoid sanitize runtime error by making always non-zero
+    emr_rectangle_t rectangle[rectangle_count ? rectangle_count : 1];
     emr_ellipse_t circle[circle_count ? circle_count : 1];
     emr_polygon_t hexagon[hexagon_count ? hexagon_count : 1];
     emr_exttextoutw_t text[string_count ? string_count: 1];
-    int text_fsizes[string_count ? string_count: 1];
+    float text_fsizes[string_count ? string_count: 1];
     int text_haligns[string_count ? string_count: 1];
 #else
     rectangle = (emr_rectangle_t*) _alloca(rectangle_count * sizeof (emr_rectangle_t));
     circle = (emr_ellipse_t*) _alloca(circle_count * sizeof (emr_ellipse_t));
     hexagon = (emr_polygon_t*) _alloca(hexagon_count * sizeof (emr_polygon_t));
     text = (emr_exttextoutw_t*) _alloca(string_count * sizeof (emr_exttextoutw_t));
-    text_fsizes = (int *) _alloca(string_count * sizeof (int));
+    text_fsizes = (float *) _alloca(string_count * sizeof (float));
     text_haligns = (int *) _alloca(string_count * sizeof (int));
 #endif
 
@@ -274,8 +277,8 @@ INTERNAL int emf_plot(struct zint_symbol *symbol, int rotate_angle) {
         }
     }
 
-    width = ceil(symbol->vector->width);
-    height = ceil(symbol->vector->height);
+    width = (int) ceil(symbol->vector->width);
+    height = (int) ceil(symbol->vector->height);
 
     /* Header */
     emr_header.type = 0x00000001; // EMR_HEADER
@@ -293,7 +296,7 @@ INTERNAL int emf_plot(struct zint_symbol *symbol, int rotate_angle) {
     if (symbol->symbology == BARCODE_ULTRA) {
         emr_header.emf_header.handles = 11; // Number of graphics objects
     } else {
-        emr_header.emf_header.handles = fsize2 ? 5 : 4;
+        emr_header.emf_header.handles = fsize2 != 0.0f ? 5 : 4;
     }
     emr_header.emf_header.reserved = 0x0000;
     emr_header.emf_header.n_description = 0;
@@ -417,7 +420,7 @@ INTERNAL int emf_plot(struct zint_symbol *symbol, int rotate_angle) {
 
     if (draw_background) {
         /* Make background from a rectangle */
-        background.type = 0x0000002b; // EMR_RECTANGLE;
+        background.type = 0x0000002b; // EMR_RECTANGLE
         background.size = 24;
         background.box.top = 0;
         background.box.left = 0;
@@ -431,12 +434,12 @@ INTERNAL int emf_plot(struct zint_symbol *symbol, int rotate_angle) {
     rect = symbol->vector->rectangles;
     this_rectangle = 0;
     while (rect) {
-        rectangle[this_rectangle].type = 0x0000002b; // EMR_RECTANGLE;
+        rectangle[this_rectangle].type = 0x0000002b; // EMR_RECTANGLE
         rectangle[this_rectangle].size = 24;
-        rectangle[this_rectangle].box.top = rect->y;
-        rectangle[this_rectangle].box.bottom = rect->y + rect->height;
-        rectangle[this_rectangle].box.left = rect->x;
-        rectangle[this_rectangle].box.right = rect->x + rect->width;
+        rectangle[this_rectangle].box.top = (int32_t) rect->y;
+        rectangle[this_rectangle].box.bottom = (int32_t) (rect->y + rect->height);
+        rectangle[this_rectangle].box.left = (int32_t) rect->x;
+        rectangle[this_rectangle].box.right = (int32_t) (rect->x + rect->width);
         this_rectangle++;
         bytecount += 24;
         recordcount++;
@@ -454,10 +457,10 @@ INTERNAL int emf_plot(struct zint_symbol *symbol, int rotate_angle) {
         }
         circle[this_circle].type = 0x0000002a; // EMR_ELLIPSE
         circle[this_circle].size = 24;
-        circle[this_circle].box.top = circ->y - radius;
-        circle[this_circle].box.bottom = circ->y + radius;
-        circle[this_circle].box.left = circ->x - radius;
-        circle[this_circle].box.right = circ->x + radius;
+        circle[this_circle].box.top = (int32_t) (circ->y - radius);
+        circle[this_circle].box.bottom = (int32_t) (circ->y + radius);
+        circle[this_circle].box.left = (int32_t) (circ->x - radius);
+        circle[this_circle].box.right = (int32_t) (circ->x + radius);
         this_circle++;
         bytecount += 24;
         recordcount++;
@@ -507,18 +510,18 @@ INTERNAL int emf_plot(struct zint_symbol *symbol, int rotate_angle) {
             fx = hex->x - half_radius;
         }
 
-        hexagon[this_hexagon].a_points_a.x = ax;
-        hexagon[this_hexagon].a_points_a.y = ay;
-        hexagon[this_hexagon].a_points_b.x = bx;
-        hexagon[this_hexagon].a_points_b.y = by;
-        hexagon[this_hexagon].a_points_c.x = cx;
-        hexagon[this_hexagon].a_points_c.y = cy;
-        hexagon[this_hexagon].a_points_d.x = dx;
-        hexagon[this_hexagon].a_points_d.y = dy;
-        hexagon[this_hexagon].a_points_e.x = ex;
-        hexagon[this_hexagon].a_points_e.y = ey;
-        hexagon[this_hexagon].a_points_f.x = fx;
-        hexagon[this_hexagon].a_points_f.y = fy;
+        hexagon[this_hexagon].a_points_a.x = (int32_t) ax;
+        hexagon[this_hexagon].a_points_a.y = (int32_t) ay;
+        hexagon[this_hexagon].a_points_b.x = (int32_t) bx;
+        hexagon[this_hexagon].a_points_b.y = (int32_t) by;
+        hexagon[this_hexagon].a_points_c.x = (int32_t) cx;
+        hexagon[this_hexagon].a_points_c.y = (int32_t) cy;
+        hexagon[this_hexagon].a_points_d.x = (int32_t) dx;
+        hexagon[this_hexagon].a_points_d.y = (int32_t) dy;
+        hexagon[this_hexagon].a_points_e.x = (int32_t) ex;
+        hexagon[this_hexagon].a_points_e.y = (int32_t) ey;
+        hexagon[this_hexagon].a_points_f.x = (int32_t) fx;
+        hexagon[this_hexagon].a_points_f.y = (int32_t) fy;
 
         hexagon[this_hexagon].bounds.top = hexagon[this_hexagon].a_points_d.y;
         hexagon[this_hexagon].bounds.bottom = hexagon[this_hexagon].a_points_a.y;
@@ -532,12 +535,13 @@ INTERNAL int emf_plot(struct zint_symbol *symbol, int rotate_angle) {
 
     /* Create font records, alignment records and text color */
     if (symbol->vector->strings) {
-        bold = (symbol->output_options & BOLD_TEXT) && (!is_extendable(symbol->symbology) || (symbol->output_options & SMALL_TEXT));
+        bold = (symbol->output_options & BOLD_TEXT) &&
+                (!is_extendable(symbol->symbology) || (symbol->output_options & SMALL_TEXT));
         memset(&emr_extcreatefontindirectw, 0, sizeof(emr_extcreatefontindirectw));
         emr_extcreatefontindirectw.type = 0x00000052; // EMR_EXTCREATEFONTINDIRECTW
         emr_extcreatefontindirectw.size = 104;
         emr_extcreatefontindirectw.ih_fonts = 11;
-        emr_extcreatefontindirectw.elw.height = fsize;
+        emr_extcreatefontindirectw.elw.height = (int32_t) fsize;
         emr_extcreatefontindirectw.elw.width = 0; // automatic
         emr_extcreatefontindirectw.elw.weight = bold ? 700 : 400;
         emr_extcreatefontindirectw.elw.char_set = 0x00; // ANSI_CHARSET
@@ -557,7 +561,7 @@ INTERNAL int emf_plot(struct zint_symbol *symbol, int rotate_angle) {
         if (fsize2) {
             memcpy(&emr_extcreatefontindirectw2, &emr_extcreatefontindirectw, sizeof(emr_extcreatefontindirectw));
             emr_extcreatefontindirectw2.ih_fonts = 12;
-            emr_extcreatefontindirectw2.elw.height = fsize2;
+            emr_extcreatefontindirectw2.elw.height = (int32_t) fsize2;
             bytecount += 104;
             recordcount++;
 
@@ -626,8 +630,8 @@ INTERNAL int emf_plot(struct zint_symbol *symbol, int rotate_angle) {
             text[this_text].i_graphics_mode = 0x00000002; // GM_ADVANCED
             text[this_text].ex_scale = 1.0f;
             text[this_text].ey_scale = 1.0f;
-            text[this_text].w_emr_text.reference.x = str->x;
-            text[this_text].w_emr_text.reference.y = str->y;
+            text[this_text].w_emr_text.reference.x = (int32_t) str->x;
+            text[this_text].w_emr_text.reference.y = (int32_t) str->y;
             text[this_text].w_emr_text.chars = utfle_len;
             text[this_text].w_emr_text.off_string = 76;
             text[this_text].w_emr_text.options = 0;
@@ -770,7 +774,7 @@ INTERNAL int emf_plot(struct zint_symbol *symbol, int rotate_angle) {
     current_fsize = fsize;
     current_halign = -1;
     for (i = 0; i < string_count; i++) {
-        if (text_fsizes[i] != current_fsize) { // NOLINT(clang-analyzer-core.UndefinedBinaryOperatorResult) suppress clang-tidy warning: text_fsizes fully set
+        if (text_fsizes[i] != current_fsize) {
             current_fsize = text_fsizes[i];
             fwrite(&emr_selectobject_font2, sizeof (emr_selectobject_t), 1, emf_file);
         }
diff --git a/backend/gb18030.c b/backend/gb18030.c
index 7b8d64fd..caa816fa 100644
--- a/backend/gb18030.c
+++ b/backend/gb18030.c
@@ -81,7 +81,7 @@ static const unsigned short cp936ext_pagefe[24] = {
   0xa6e5, 0xa6e8, 0xa6e9, 0xa6ea, 0xa6eb, 0x0000, 0x0000, 0x0000, /*0x40-0x47*/
 };
 
-static int cp936ext_wctomb(unsigned int *r, unsigned int wc) {
+static int cp936ext_wctomb(unsigned int *r, const unsigned int wc) {
     unsigned short c = 0;
     if (wc >= 0x0140 && wc < 0x0150) {
         c = cp936ext_page01[wc-0x0140];
@@ -2383,7 +2383,7 @@ static const Summary16 gbkext_inv_uni2indx_pagefe[31] = {
   { 14311, 0x0000 }, { 14311, 0x0000 }, { 14311, 0x0014 },
 };
 
-static int gbkext_inv_wctomb(unsigned int *r, unsigned int wc) {
+static int gbkext_inv_wctomb(unsigned int *r, const unsigned int wc) {
     const Summary16 *summary = NULL;
     if (wc >= 0x0200 && wc < 0x02e0) {
         summary = &gbkext_inv_uni2indx_page02[(wc>>4)-0x020];
@@ -2424,7 +2424,7 @@ static int gbkext_inv_wctomb(unsigned int *r, unsigned int wc) {
  * GBK (libiconv-1.16/lib/gbk.h)
  */
 
-static int gbk_wctomb(unsigned int *r, unsigned int wc) {
+static int gbk_wctomb(unsigned int *r, const unsigned int wc) {
     int ret;
 
     /* ZINT: Note these mappings U+30FB and U+2015 different from GB 2312 */
@@ -2553,7 +2553,7 @@ static const unsigned short gb18030ext_pagefe[16] = {
   0xa6ed, 0xa6f3, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, /*0x18-0x1f*/
 };
 
-static int gb18030ext_wctomb(unsigned int *r, unsigned int wc) {
+static int gb18030ext_wctomb(unsigned int *r, const unsigned int wc) {
     unsigned short c = 0;
     if (wc == 0x01f9) {
         c = 0xa8bf;
@@ -2727,7 +2727,7 @@ static const unsigned short gb18030uni_ranges[206] = {
   25994, 25998, 26012, 26016, 26110, 26116
 };
 
-static int gb18030uni_wctomb(unsigned int *r1, unsigned int *r2, unsigned int wc) {
+static int gb18030uni_wctomb(unsigned int *r1, unsigned int *r2, const unsigned int wc) {
     unsigned int i = wc;
     if (i >= 0x0080 && i <= 0xffff) {
         if (i == 0xe7c7) {
@@ -2798,7 +2798,7 @@ static const unsigned short gb18030_pua2charset[31*3] = {
   0xe864, 0xe864,  0xfea0,
 };
 
-INTERNAL int gb18030_wctomb_zint(unsigned int *r1, unsigned int *r2, unsigned int wc) {
+INTERNAL int gb18030_wctomb_zint(unsigned int *r1, unsigned int *r2, const unsigned int wc) {
     int ret;
 
     /* Code set 0 (ASCII) */
@@ -2871,7 +2871,7 @@ INTERNAL int gb18030_wctomb_zint(unsigned int *r1, unsigned int *r2, unsigned in
 
 /* Convert UTF-8 string to GB 18030 and place in array of ints */
 INTERNAL int gb18030_utf8tomb(struct zint_symbol *symbol, const unsigned char source[], int *p_length,
-            unsigned int *gbdata) {
+                unsigned int *gbdata) {
     int error_number, ret;
     unsigned int i, j, length;
 #ifndef _MSC_VER
@@ -2906,8 +2906,8 @@ INTERNAL int gb18030_utf8tomb(struct zint_symbol *symbol, const unsigned char so
 }
 
 /* Convert UTF-8 string to single byte ECI and place in array of ints */
-INTERNAL int gb18030_utf8tosb(int eci, const unsigned char source[], int *p_length, unsigned int *gbdata,
-            int full_multibyte) {
+INTERNAL int gb18030_utf8tosb(const int eci, const unsigned char source[], int *p_length, unsigned int *gbdata,
+                const int full_multibyte) {
     int error_number;
 #ifndef _MSC_VER
     unsigned char single_byte[*p_length + 1];
@@ -2926,9 +2926,10 @@ INTERNAL int gb18030_utf8tosb(int eci, const unsigned char source[], int *p_leng
     return 0;
 }
 
-/* If `full_multibyte` set, copy byte input stream to array of ints, putting double-bytes that match HANXIN Chinese
- * mode in single entry, and quad-bytes in 2 entries. If `full_multibyte` not set, do a straight copy */
-INTERNAL void gb18030_cpy(const unsigned char source[], int *p_length, unsigned int *gbdata, int full_multibyte) {
+/* If `full_multibyte` set, copy byte input stream to array of ints, putting double-bytes that match HANXIN
+ * Chinese mode in single entry, and quad-bytes in 2 entries. If `full_multibyte` not set, do a straight copy */
+INTERNAL void gb18030_cpy(const unsigned char source[], int *p_length, unsigned int *gbdata,
+                const int full_multibyte) {
     unsigned int i, j, length;
     int done;
     unsigned char c1, c2, c3, c4;
diff --git a/backend/gb18030.h b/backend/gb18030.h
index d2731654..e285600f 100644
--- a/backend/gb18030.h
+++ b/backend/gb18030.h
@@ -37,12 +37,13 @@
 extern "C" {
 #endif /* __cplusplus */
 
-INTERNAL int gb18030_wctomb_zint(unsigned int *r1, unsigned int *r2, unsigned int wc);
+INTERNAL int gb18030_wctomb_zint(unsigned int *r1, unsigned int *r2, const unsigned int wc);
 INTERNAL int gb18030_utf8tomb(struct zint_symbol *symbol, const unsigned char source[], int *p_length,
-            unsigned int *gbdata);
-INTERNAL int gb18030_utf8tosb(int eci, const unsigned char source[], int *p_length, unsigned int *gbdata,
-            int full_multibyte);
-INTERNAL void gb18030_cpy(const unsigned char source[], int *p_length, unsigned int *gbdata, int full_multibyte);
+                unsigned int *gbdata);
+INTERNAL int gb18030_utf8tosb(const int eci, const unsigned char source[], int *p_length, unsigned int *gbdata,
+                const int full_multibyte);
+INTERNAL void gb18030_cpy(const unsigned char source[], int *p_length, unsigned int *gbdata,
+                const int full_multibyte);
 
 #ifdef __cplusplus
 }
diff --git a/backend/gb2312.c b/backend/gb2312.c
index ea2c849f..fd96375c 100644
--- a/backend/gb2312.c
+++ b/backend/gb2312.c
@@ -1502,7 +1502,7 @@ static const Summary16 gb2312_uni2indx_pageff[15] = {
   { 7441, 0x0000 }, { 7441, 0x0000 }, { 7441, 0x002b },
 };
 
-INTERNAL int gb2312_wctomb_zint(unsigned int *r, unsigned int wc) {
+INTERNAL int gb2312_wctomb_zint(unsigned int *r, const unsigned int wc) {
     const Summary16 *summary = NULL;
     if (wc < 0x0460) {
         if (wc == 0x00b7) { /* ZINT: Patched to duplicate map to 0xA1A4 */
@@ -1545,7 +1545,7 @@ INTERNAL int gb2312_wctomb_zint(unsigned int *r, unsigned int wc) {
 
 /* Convert UTF-8 string to GB 2312 (EUC-CN) and place in array of ints */
 INTERNAL int gb2312_utf8tomb(struct zint_symbol *symbol, const unsigned char source[], int *p_length,
-            unsigned int *gbdata) {
+                unsigned int *gbdata) {
     int error_number;
     unsigned int i, length;
 #ifndef _MSC_VER
@@ -1574,8 +1574,8 @@ INTERNAL int gb2312_utf8tomb(struct zint_symbol *symbol, const unsigned char sou
 }
 
 /* Convert UTF-8 string to single byte ECI and place in array of ints */
-INTERNAL int gb2312_utf8tosb(int eci, const unsigned char source[], int *p_length, unsigned int *gbdata,
-            int full_multibyte) {
+INTERNAL int gb2312_utf8tosb(const int eci, const unsigned char source[], int *p_length, unsigned int *gbdata,
+                const int full_multibyte) {
     int error_number;
 #ifndef _MSC_VER
     unsigned char single_byte[*p_length + 1];
@@ -1594,9 +1594,10 @@ INTERNAL int gb2312_utf8tosb(int eci, const unsigned char source[], int *p_lengt
     return 0;
 }
 
-/* If `full_multibyte` set, copy byte input stream to array of ints, putting double-bytes that match GRIDMATRIX Chinese
- * mode in a single entry. If `full_multibyte` not set, do a straight copy */
-INTERNAL void gb2312_cpy(const unsigned char source[], int *p_length, unsigned int *gbdata, int full_multibyte) {
+/* If `full_multibyte` set, copy byte input stream to array of ints, putting double-bytes that match GRIDMATRIX
+ * Chinese mode in a single entry. If `full_multibyte` not set, do a straight copy */
+INTERNAL void gb2312_cpy(const unsigned char source[], int *p_length, unsigned int *gbdata,
+                const int full_multibyte) {
     unsigned int i, j, length;
     unsigned char c1, c2;
 
diff --git a/backend/gb2312.h b/backend/gb2312.h
index c83d4c6a..27ed6453 100644
--- a/backend/gb2312.h
+++ b/backend/gb2312.h
@@ -37,12 +37,13 @@
 extern "C" {
 #endif /* __cplusplus */
 
-INTERNAL int gb2312_wctomb_zint(unsigned int *r, unsigned int wc);
+INTERNAL int gb2312_wctomb_zint(unsigned int *r, const unsigned int wc);
 INTERNAL int gb2312_utf8tomb(struct zint_symbol *symbol, const unsigned char source[], int *p_length,
-            unsigned int *gbdata);
-INTERNAL int gb2312_utf8tosb(int eci, const unsigned char source[], int *p_length, unsigned int *gbdata,
-            int full_multibyte);
-INTERNAL void gb2312_cpy(const unsigned char source[], int *p_length, unsigned int *gbdata, int full_multibyte);
+                unsigned int *gbdata);
+INTERNAL int gb2312_utf8tosb(const int eci, const unsigned char source[], int *p_length, unsigned int *gbdata,
+                const int full_multibyte);
+INTERNAL void gb2312_cpy(const unsigned char source[], int *p_length, unsigned int *gbdata,
+                const int full_multibyte);
 
 #ifdef __cplusplus
 }
diff --git a/backend/imail.c b/backend/imail.c
index 1b90efe8..9291c561 100644
--- a/backend/imail.c
+++ b/backend/imail.c
@@ -251,7 +251,7 @@ INTERNAL int imail(struct zint_symbol *symbol, unsigned char source[], int lengt
     large_int byte_array_reg;
     unsigned char byte_array[13];
     unsigned short usps_crc;
-    int codeword[10];
+    unsigned int codeword[10];
     unsigned short characters[10];
     short int bar_map[130];
     int zip_len, len;
@@ -362,15 +362,15 @@ INTERNAL int imail(struct zint_symbol *symbol, unsigned char source[], int lengt
     /* *** Step 3 - Conversion from Binary Data to Codewords *** */
 
     /* start with codeword J which is base 636 */
-    codeword[9] = large_div_u64(&accum, 636);
+    codeword[9] = (unsigned int) large_div_u64(&accum, 636);
 
     /* then codewords I to B with base 1365 */
 
     for (j = 8; j > 0; j--) {
-        codeword[j] = large_div_u64(&accum, 1365);
+        codeword[j] = (unsigned int) large_div_u64(&accum, 1365);
     }
 
-    codeword[0] = large_lo(&accum);
+    codeword[0] = (unsigned int) large_lo(&accum);
 
     /* *** Step 4 - Inserting Additional Information into Codewords *** */
 
diff --git a/backend/large.c b/backend/large.c
index 45b53f8b..41203b33 100644
--- a/backend/large.c
+++ b/backend/large.c
@@ -211,7 +211,8 @@ INTERNAL uint64_t large_div_u64(large_int *t, uint64_t v) {
     /* Note qhat1 will be exact as have fully divided by 2-digit divisor
      * (can only be too high by 1 (and require "add back" step) if divisor at least 3 digits) */
 
-    rnhilo1 = (tnhi << 32) + tnlo1 - (qhat1 * v); /* Note high digit (if any) of both tnhi and (qhat1 * v) shifted out */
+    /* Note high digit (if any) of both tnhi and (qhat1 * v) shifted out */
+    rnhilo1 = (tnhi << 32) + tnlo1 - (qhat1 * v);
 
     /* Compute qhat0 estimate */
 
@@ -255,21 +256,22 @@ INTERNAL void large_uint_array(const large_int *t, unsigned int *uint_array, int
     }
     mask = ~(((uint64_t) -1) << bits);
     for (i = 0, j = 0; i < size && j < 64; i++, j += bits) {
-        uint_array[size - 1 - i] = (t->lo >> j) & mask; /* Little-endian order */
+        uint_array[size - 1 - i] = (unsigned int) ((t->lo >> j) & mask); /* Little-endian order */
     }
     if (i < size) {
         if (j != 64) {
             j -= 64;
             /* (first j bits of t->hi) << (bits - j) | (last (bits - j) bits of t->lo) */
-            uint_array[size - i] = ((t->hi & ~((((uint64_t) -1) << j))) << (bits - j)) | (t->lo >> (64 - (bits - j)) & mask);
+            uint_array[size - i] = (unsigned int) (((t->hi & ~((((uint64_t) -1) << j))) << (bits - j))
+                                                    | (t->lo >> (64 - (bits - j)) & mask));
         } else {
             j = 0;
         }
         for (; i < size && j < 64; i++, j += bits) {
-            uint_array[size - 1 - i] = (t->hi >> j) & mask;
+            uint_array[size - 1 - i] = (unsigned int) ((t->hi >> j) & mask);
         }
         if (i < size && j != 128) {
-            uint_array[size - 1 - i] = t->hi >> (j - bits) & mask;
+            uint_array[size - 1 - i] = (unsigned int) (t->hi >> (j - bits) & mask);
         }
     }
 }
@@ -299,10 +301,10 @@ INTERNAL void large_print(large_int *t) {
 
 /* Format large_int into buffer, which should be at least 35 chars in size */
 INTERNAL char *large_dump(large_int *t, char *buf) {
-    unsigned int tlo1 = large_lo(t) >> 32;
-    unsigned int tlo0 = large_lo(t) & MASK32;
-    unsigned int thi1 = large_hi(t) >> 32;
-    unsigned int thi0 = large_hi(t) & MASK32;
+    unsigned int tlo1 = (unsigned int) (large_lo(t) >> 32);
+    unsigned int tlo0 = (unsigned int) (large_lo(t) & MASK32);
+    unsigned int thi1 = (unsigned int) (large_hi(t) >> 32);
+    unsigned int thi0 = (unsigned int) (large_hi(t) & MASK32);
 
     if (thi1) {
         sprintf(buf, "0x%X%08X%08X%08X", thi1, thi0, tlo1, tlo0);
diff --git a/backend/library.c b/backend/library.c
index 236eb231..5ec9900f 100644
--- a/backend/library.c
+++ b/backend/library.c
@@ -127,14 +127,14 @@ INTERNAL int get_best_eci(unsigned char source[], int length); /* Calculate suit
 INTERNAL int utf_to_eci(const int eci, const unsigned char source[], unsigned char dest[], int *length); /* Convert Unicode to other encodings */
 
 INTERNAL int eanx(struct zint_symbol *symbol, unsigned char source[], int length); /* EAN system barcodes */
-INTERNAL int c39(struct zint_symbol *symbol, unsigned char source[], const size_t length); /* Code 3 from 9 (or Code 39) */
+INTERNAL int c39(struct zint_symbol *symbol, unsigned char source[], int length); /* Code 3 from 9 (or Code 39) */
 INTERNAL int pharmazentral(struct zint_symbol *symbol, unsigned char source[], int length); /* Pharmazentral Nummer (PZN) */
 INTERNAL int ec39(struct zint_symbol *symbol, unsigned char source[], int length); /* Extended Code 3 from 9 (or Code 39+) */
 INTERNAL int codabar(struct zint_symbol *symbol, unsigned char source[], int length); /* Codabar - a simple substitution cipher */
 INTERNAL int matrix_two_of_five(struct zint_symbol *symbol, unsigned char source[], int length); /* Code 2 of 5 Standard (& Matrix) */
 INTERNAL int industrial_two_of_five(struct zint_symbol *symbol, unsigned char source[], int length); /* Code 2 of 5 Industrial */
 INTERNAL int iata_two_of_five(struct zint_symbol *symbol, unsigned char source[], int length); /* Code 2 of 5 IATA */
-INTERNAL int interleaved_two_of_five(struct zint_symbol *symbol, const unsigned char source[], size_t length); /* Code 2 of 5 Interleaved */
+INTERNAL int interleaved_two_of_five(struct zint_symbol *symbol, unsigned char source[], int length); /* Code 2 of 5 Interleaved */
 INTERNAL int logic_two_of_five(struct zint_symbol *symbol, unsigned char source[], int length); /* Code 2 of 5 Data Logic */
 INTERNAL int itf14(struct zint_symbol *symbol, unsigned char source[], int length); /* ITF-14 */
 INTERNAL int dpleit(struct zint_symbol *symbol, unsigned char source[], int length); /* Deutsche Post Leitcode */
@@ -144,9 +144,9 @@ INTERNAL int code_128(struct zint_symbol *symbol, unsigned char source[], int le
 INTERNAL int ean_128(struct zint_symbol *symbol, unsigned char source[], int length); /* EAN-128 (GS1-128) */
 INTERNAL int code_11(struct zint_symbol *symbol, unsigned char source[], int length); /* Code 11 */
 INTERNAL int msi_handle(struct zint_symbol *symbol, unsigned char source[], int length); /* MSI Plessey */
-INTERNAL int telepen(struct zint_symbol *symbol, unsigned char source[], const size_t length); /* Telepen ASCII */
-INTERNAL int telepen_num(struct zint_symbol *symbol, unsigned char source[], const size_t length); /* Telepen Numeric */
-INTERNAL int plessey(struct zint_symbol *symbol, unsigned char source[], const size_t length); /* Plessey Code */
+INTERNAL int telepen(struct zint_symbol *symbol, unsigned char source[], int length); /* Telepen ASCII */
+INTERNAL int telepen_num(struct zint_symbol *symbol, unsigned char source[], int length); /* Telepen Numeric */
+INTERNAL int plessey(struct zint_symbol *symbol, unsigned char source[], int length); /* Plessey Code */
 INTERNAL int pharma_one(struct zint_symbol *symbol, unsigned char source[], int length); /* Pharmacode One Track */
 INTERNAL int flattermarken(struct zint_symbol *symbol, unsigned char source[], int length); /* Flattermarken */
 INTERNAL int fim(struct zint_symbol *symbol, unsigned char source[], int length); /* Facing Identification Mark */
@@ -156,7 +156,7 @@ INTERNAL int planet_plot(struct zint_symbol *symbol, unsigned char source[], int
 INTERNAL int imail(struct zint_symbol *symbol, unsigned char source[], int length); /* Intelligent Mail (aka USPS OneCode) */
 INTERNAL int royal_plot(struct zint_symbol *symbol, unsigned char source[], int length); /* RM4SCC */
 INTERNAL int australia_post(struct zint_symbol *symbol, unsigned char source[], int length); /* Australia Post 4-state */
-INTERNAL int code16k(struct zint_symbol *symbol, unsigned char source[],const size_t length); /* Code 16k */
+INTERNAL int code16k(struct zint_symbol *symbol, unsigned char source[], int length); /* Code 16k */
 INTERNAL int pdf417enc(struct zint_symbol *symbol, unsigned char source[], int length); /* PDF417 */
 INTERNAL int micro_pdf417(struct zint_symbol *symbol, unsigned char chaine[], int length); /* Micro PDF417 */
 INTERNAL int maxicode(struct zint_symbol *symbol, unsigned char source[], int length); /* Maxicode */
@@ -174,20 +174,20 @@ INTERNAL int microqr(struct zint_symbol *symbol, unsigned char source[], int len
 INTERNAL int aztec_runes(struct zint_symbol *symbol, unsigned char source[], int length); /* Aztec Runes */
 INTERNAL int korea_post(struct zint_symbol *symbol, unsigned char source[], int length); /* Korea Post */
 INTERNAL int japan_post(struct zint_symbol *symbol, unsigned char source[], int length); /* Japanese Post */
-INTERNAL int code_49(struct zint_symbol *symbol, unsigned char source[], const int length); /* Code 49 */
+INTERNAL int code_49(struct zint_symbol *symbol, unsigned char source[], int length); /* Code 49 */
 INTERNAL int channel_code(struct zint_symbol *symbol, unsigned char source[], int length); /* Channel Code */
 INTERNAL int code_one(struct zint_symbol *symbol, unsigned char source[], int length); /* Code One */
 INTERNAL int grid_matrix(struct zint_symbol *symbol, unsigned char source[], int length); /* Grid Matrix */
-INTERNAL int han_xin(struct zint_symbol * symbol, unsigned char source[], int length); /* Han Xin */
-INTERNAL int dotcode(struct zint_symbol * symbol, const unsigned char source[], int length); /* DotCode */
+INTERNAL int han_xin(struct zint_symbol *symbol, unsigned char source[], int length); /* Han Xin */
+INTERNAL int dotcode(struct zint_symbol *symbol, unsigned char source[], int length); /* DotCode */
 INTERNAL int codablock(struct zint_symbol *symbol, unsigned char source[], int length); /* Codablock */
 INTERNAL int upnqr(struct zint_symbol *symbol, unsigned char source[], int length); /* UPNQR */
 INTERNAL int qr_code(struct zint_symbol *symbol, unsigned char source[], int length); /* QR Code */
-INTERNAL int dmatrix(struct zint_symbol *symbol, const unsigned char source[], const size_t in_length); /* Data Matrix (IEC16022) */
-INTERNAL int vin(struct zint_symbol *symbol, const unsigned char source[], const size_t in_length); /* VIN Code (Vehicle Identification Number) */
-INTERNAL int mailmark(struct zint_symbol *symbol, const unsigned char source[], const size_t in_length); /* Royal Mail 4-state Mailmark */
-INTERNAL int ultracode(struct zint_symbol *symbol, const unsigned char source[], const size_t in_length); /* Ultracode */
-INTERNAL int rmqr(struct zint_symbol *symbol, unsigned char source[], int in_length); /* rMQR */
+INTERNAL int dmatrix(struct zint_symbol *symbol, unsigned char source[], int length); /* Data Matrix (IEC16022) */
+INTERNAL int vin(struct zint_symbol *symbol, unsigned char source[], int length); /* VIN Code (Vehicle Identification Number) */
+INTERNAL int mailmark(struct zint_symbol *symbol, unsigned char source[], int length); /* Royal Mail 4-state Mailmark */
+INTERNAL int ultracode(struct zint_symbol *symbol, unsigned char source[], int length); /* Ultracode */
+INTERNAL int rmqr(struct zint_symbol *symbol, unsigned char source[], int length); /* rMQR */
 INTERNAL int dpd_parcel(struct zint_symbol *symbol, unsigned char source[], int length); /* DPD Code */
 
 INTERNAL int plot_raster(struct zint_symbol *symbol, int rotate_angle, int file_type); /* Plot to PNG/BMP/PCX */
@@ -1300,7 +1300,8 @@ int ZBarcode_Encode(struct zint_symbol *symbol, const unsigned char *source, int
 
     if (((symbol->input_mode & 0x07) == GS1_MODE) || (check_force_gs1(symbol->symbology))) {
         if (gs1_compliant(symbol->symbology) == 1) {
-            // Reduce input for composite and non-forced symbologies, others (EAN128 and RSS_EXP based) will handle it themselves
+            // Reduce input for composite and non-forced symbologies, others (EAN128 and RSS_EXP based) will
+            // handle it themselves
             if (is_composite(symbol->symbology) || !check_force_gs1(symbol->symbology)) {
 #ifndef _MSC_VER
                 unsigned char reduced[in_length + 1];
@@ -1591,7 +1592,8 @@ int ZBarcode_Encode_File(struct zint_symbol *symbol, char *filename) {
         fileLen = ftell(file);
         fseek(file, 0, SEEK_SET);
 
-        if (fileLen <= 0 || fileLen == LONG_MAX) { /* On many Linux distros ftell() returns LONG_MAX not -1 on error */
+        /* On many Linux distros ftell() returns LONG_MAX not -1 on error */
+        if (fileLen <= 0 || fileLen == LONG_MAX) {
             strcpy(symbol->errtxt, "235: Input file empty or unseekable");
             error_tag(symbol->errtxt, ZINT_ERROR_INVALID_DATA);
             fclose(file);
diff --git a/backend/mailmark.c b/backend/mailmark.c
index f498b412..1411cd02 100644
--- a/backend/mailmark.c
+++ b/backend/mailmark.c
@@ -39,7 +39,6 @@
  * 
  */
 
-#include <string.h>
 #include <stdio.h>
 #ifdef _MSC_VER
 #include <malloc.h>
@@ -61,13 +60,13 @@ static const char *postcode_format[6] = {
 };
 
 // Data/Check Symbols from Table 5
-static const unsigned short data_symbol_odd[32] = {
+static const unsigned char data_symbol_odd[32] = {
     0x01, 0x02, 0x04, 0x07, 0x08, 0x0B, 0x0D, 0x0E, 0x10, 0x13, 0x15, 0x16,
     0x19, 0x1A, 0x1C, 0x1F, 0x20, 0x23, 0x25, 0x26, 0x29, 0x2A, 0x2C, 0x2F,
     0x31, 0x32, 0x34, 0x37, 0x38, 0x3B, 0x3D, 0x3E
 };
 
-static const unsigned short data_symbol_even[30] = {
+static const unsigned char data_symbol_even[30] = {
     0x03, 0x05, 0x06, 0x09, 0x0A, 0x0C, 0x0F, 0x11, 0x12, 0x14, 0x17, 0x18,
     0x1B, 0x1D, 0x1E, 0x21, 0x22, 0x24, 0x27, 0x28, 0x2B, 0x2D, 0x2E, 0x30,
     0x33, 0x35, 0x36, 0x39, 0x3A, 0x3C
@@ -122,7 +121,7 @@ static int verify_postcode(char* postcode, int type) {
 }
 
 /* Royal Mail Mailmark */
-INTERNAL int mailmark(struct zint_symbol *symbol, const unsigned char source[], const size_t in_length) {
+INTERNAL int mailmark(struct zint_symbol *symbol, unsigned char source[], int length) {
     
     char local_source[28];
     int format;
@@ -143,7 +142,6 @@ INTERNAL int mailmark(struct zint_symbol *symbol, const unsigned char source[],
     char bar[80];
     int check_count;
     int i, j, len;
-    int length = (int) in_length;
     rs_t rs;
     
     if (length > 26) {
@@ -395,11 +393,11 @@ INTERNAL int mailmark(struct zint_symbol *symbol, const unsigned char source[],
     // Conversion from Consolidated Data Value to Data Numbers
 
     for (j = data_top; j >= (data_step + 1); j--) {
-        data[j] = large_div_u64(&cdv, 32);
+        data[j] = (unsigned char) large_div_u64(&cdv, 32);
     }
     
     for (j = data_step; j >= 0; j--) {
-        data[j] = large_div_u64(&cdv, 30);
+        data[j] = (unsigned char) large_div_u64(&cdv, 30);
     }
     
     // Generation of Reed-Solomon Check Numbers
@@ -476,7 +474,7 @@ INTERNAL int mailmark(struct zint_symbol *symbol, const unsigned char source[],
     
     /* Translate 4-state data pattern to symbol */
     j = 0;
-    for (i = 0, len = strlen(bar); i < len; i++) {
+    for (i = 0, len = (int) strlen(bar); i < len; i++) {
         if ((bar[i] == 'F') || (bar[i] == 'A')) {
             set_module(symbol, 0, j);
         }
diff --git a/backend/medical.c b/backend/medical.c
index af50b2e2..d110502e 100644
--- a/backend/medical.c
+++ b/backend/medical.c
@@ -34,7 +34,7 @@
 #include <stdio.h>
 #include "common.h"
 
-INTERNAL int c39(struct zint_symbol *symbol, unsigned char source[], const size_t length);
+INTERNAL int c39(struct zint_symbol *symbol, unsigned char source[], int length);
 
 /* Codabar table checked against EN 798:1995 */
 
@@ -93,7 +93,7 @@ INTERNAL int pharma_one(struct zint_symbol *symbol, unsigned char source[], int
         }
     } while (tester != 0);
 
-    h = strlen(inter) - 1;
+    h = (int) strlen(inter) - 1;
     *dest = '\0';
     for (counter = h; counter >= 0; counter--) {
         if (inter[counter] == 'W') {
@@ -144,7 +144,7 @@ static int pharma_two_calc(struct zint_symbol *symbol, unsigned char source[], c
         }
     } while (tester != 0);
 
-    h = strlen(inter) - 1;
+    h = (int) strlen(inter) - 1;
     for (counter = h; counter >= 0; counter--) {
         dest[h - counter] = inter[counter];
     }
@@ -176,7 +176,7 @@ INTERNAL int pharma_two(struct zint_symbol *symbol, unsigned char source[], int
     }
 
     writer = 0;
-    h = strlen(height_pattern);
+    h = (int) strlen(height_pattern);
     for (loopey = 0; loopey < h; loopey++) {
         if ((height_pattern[loopey] == '2') || (height_pattern[loopey] == '3')) {
             set_module(symbol, 0, writer);
@@ -198,7 +198,7 @@ INTERNAL int codabar(struct zint_symbol *symbol, unsigned char source[], int len
 
     int i, error_number;
     char dest[512];
-    int add_checksum, count, checksum;
+    int add_checksum, count = 0, checksum;
 
     strcpy(dest, "");
 
@@ -234,9 +234,6 @@ INTERNAL int codabar(struct zint_symbol *symbol, unsigned char source[], int len
     }
 
     add_checksum = symbol->option_2 == 1;
-    if (add_checksum) {
-        count = 0;
-    }
 
     for (i = 0; i < length; i++) {
         if (add_checksum) {
@@ -322,7 +319,7 @@ INTERNAL int code32(struct zint_symbol *symbol, unsigned char source[], int leng
     }
     risultante[6] = '\0';
     /* Plot the barcode using Code 39 */
-    error_number = c39(symbol, (unsigned char*) risultante, strlen(risultante));
+    error_number = c39(symbol, (unsigned char*) risultante, (int) strlen(risultante));
     if (error_number != 0) {
         return error_number;
     }
diff --git a/backend/pdf417.c b/backend/pdf417.c
index 83bfe663..094e4958 100644
--- a/backend/pdf417.c
+++ b/backend/pdf417.c
@@ -88,8 +88,12 @@ static const char MicroAutosize[56] = {
     1, 14, 2, 7, 3, 25, 8, 16, 5, 17, 9, 6, 10, 11, 28, 12, 19, 13, 29, 20, 30, 21, 22, 31, 23, 32, 33, 34
 };
 
-#define PDF417_MAX_LEN          2710    /* ISO/IEC 15438:2015 5.1.1 c) 3) Max possible number of characters at error correction level 0 (Numeric Compaction mode) */
-#define MICRO_PDF417_MAX_LEN    366     /* ISO/IEC 24728:2006 5.1.1 c) 3) Max possible number of characters (Numeric Compaction mode) */
+/* ISO/IEC 15438:2015 5.1.1 c) 3) Max possible number of characters at error correction level 0
+   (Numeric Compaction mode) */
+#define PDF417_MAX_LEN          2710
+
+/* ISO/IEC 24728:2006 5.1.1 c) 3) Max possible number of characters (Numeric Compaction mode) */
+#define MICRO_PDF417_MAX_LEN    366
 
 /* 866 */
 
@@ -377,8 +381,8 @@ static void textprocess(int *chainemc, int *mclength, char chaine[], int start,
     }
     /* Now translate the string chainet into codewords */
 
-    /* Default mode for PDF417 is Text Compaction Alpha (ISO/IEC 1543:2015 5.4.2.1), and for MICROPDF417 is Byte Compaction
-     * (ISO/IEC 24728:2006 5.4.3), so only add flag if not first codeword or is MICROPDF417 */
+    /* Default mode for PDF417 is Text Compaction Alpha (ISO/IEC 1543:2015 5.4.2.1), and for MICROPDF417 is Byte
+     * Compaction (ISO/IEC 24728:2006 5.4.3), so only add flag if not first codeword or is MICROPDF417 */
     if (*mclength || is_micro) {
         chainemc[(*mclength)++] = 900;
     }
@@ -409,8 +413,9 @@ INTERNAL void byteprocess(int *chainemc, int *mclength, unsigned char chaine[],
             chainemc[(*mclength)++] = 924;
             if (debug) printf("924 ");
         } else {
-            /* Default mode for MICROPDF417 is Byte Compaction (ISO/IEC 24728:2006 5.4.3), but not emitting it depends on whether
-             * an ECI has been emitted previously (or not) it appears, so simpler and safer to always emit it. */
+            /* Default mode for MICROPDF417 is Byte Compaction (ISO/IEC 24728:2006 5.4.3), but not emitting it
+             * depends on whether an ECI has been emitted previously (or not) it appears, so simpler and safer
+             * to always emit it. */
             chainemc[(*mclength)++] = 901;
             if (debug) printf("901 ");
         }
@@ -507,6 +512,7 @@ static int pdf417(struct zint_symbol *symbol, unsigned char chaine[], const int
     int total, chainemc[PDF417_MAX_LEN], mclength, c1, c2, c3, dummy[35], calcheight;
     int liste[2][PDF417_MAX_LEN] = {{0}};
     char pattern[580];
+    int bp = 0;
     int error_number = 0;
     int debug = symbol->debug & ZINT_DEBUG_PRINT;
 
@@ -733,7 +739,7 @@ static int pdf417(struct zint_symbol *symbol, unsigned char chaine[], const int
 
     /* we now encode each row */
     for (i = 0; i < symbol->rows; i++) {
-        int p;
+        bp = 0;
         for (j = 0; j < symbol->option_2; j++) {
             dummy[j + 1] = chainemc[i * symbol->option_2 + j];
         }
@@ -755,28 +761,28 @@ static int pdf417(struct zint_symbol *symbol, unsigned char chaine[], const int
                 offset = 1858; /* cluster(6) */
                 break;
         }
-        p = bin_append_posn(0x1FEA8, 17, pattern, 0); /* Row start */
+        bp = bin_append_posn(0x1FEA8, 17, pattern, bp); /* Row start */
 
         for (j = 0; j <= symbol->option_2; j++) {
-            p = bin_append_posn(pdf_bitpattern[offset + dummy[j]], 16, pattern, p);
-            pattern[p++] = '0';
+            bp = bin_append_posn(pdf_bitpattern[offset + dummy[j]], 16, pattern, bp);
+            pattern[bp++] = '0';
         }
 
         if (symbol->symbology != BARCODE_PDF417COMP) {
-            p = bin_append_posn(pdf_bitpattern[offset + dummy[j]], 16, pattern, p);
-            pattern[p++] = '0';
-            p = bin_append_posn(0x3FA29, 18, pattern, p); /* Row Stop */
+            bp = bin_append_posn(pdf_bitpattern[offset + dummy[j]], 16, pattern, bp);
+            pattern[bp++] = '0';
+            bp = bin_append_posn(0x3FA29, 18, pattern, bp); /* Row Stop */
         } else {
-            pattern[p++] = '1'; /* Compact PDF417 Stop pattern */
+            pattern[bp++] = '1'; /* Compact PDF417 Stop pattern */
         }
-        pattern[p] = '\0';
 
-        for (loop = 0; loop < p; loop++) {
+        for (loop = 0; loop < bp; loop++) {
             if (pattern[loop] == '1') {
                 set_module(symbol, i, loop);
             }
         }
     }
+    symbol->width = bp;
     
     /* Allow user to adjust height of symbol, but enforce minimum row height of 3X */
     calcheight = (int)(symbol->height / i);
@@ -787,8 +793,6 @@ static int pdf417(struct zint_symbol *symbol, unsigned char chaine[], const int
     for (j = 0; j < i; j++) {
         symbol->row_height[j] = calcheight;
     }
-    
-    symbol->width = (int) strlen(pattern);
 
     /* 843 */
     return error_number;
@@ -834,9 +838,10 @@ INTERNAL int pdf417enc(struct zint_symbol *symbol, unsigned char source[], int l
 /* like PDF417 only much smaller! */
 INTERNAL int micro_pdf417(struct zint_symbol *symbol, unsigned char chaine[], int length) {
     int i, k, j, indexchaine, indexliste, mode, longueur, mccorrection[50] = {0}, offset;
-    int total, chainemc[PDF417_MAX_LEN], mclength, dummy[5], codeerr;
+    int total, chainemc[PDF417_MAX_LEN], mclength, codeerr;
     int liste[2][PDF417_MAX_LEN] = {{0}};
     char pattern[580];
+    int bp = 0;
     int variant, LeftRAPStart, CentreRAPStart, RightRAPStart, StartCluster;
     int LeftRAP, CentreRAP, RightRAP, Cluster, loop, calcheight;
     int debug = symbol->debug & ZINT_DEBUG_PRINT;
@@ -895,28 +900,26 @@ INTERNAL int micro_pdf417(struct zint_symbol *symbol, unsigned char chaine[], in
         mclength++;
     }
 
-    if (symbol->eci > 811799) {
-        strcpy(symbol->errtxt, "473: Invalid ECI");
-        return ZINT_ERROR_INVALID_OPTION;
-    }
-
     if (symbol->eci != 0) {
+
         /* Encoding ECI assignment number, according to Table 8 */
         if (symbol->eci <= 899) {
             chainemc[mclength] = 927; /* ECI */
             mclength++;
             chainemc[mclength] = symbol->eci;
             mclength++;
-        }
-        if ((symbol->eci >= 900) && (symbol->eci <= 810899)) {
+        } else if (symbol->eci <= 810899) {
             chainemc[mclength] = 926; /* ECI */
             mclength++;
             chainemc[mclength] = (symbol->eci / 900) - 1;
             mclength++;
             chainemc[mclength] = symbol->eci % 900;
             mclength++;
-        }
-        if (symbol->eci >= 810900) {
+        } else {
+            if (symbol->eci > 811799) {
+                strcpy(symbol->errtxt, "473: Invalid ECI");
+                return ZINT_ERROR_INVALID_OPTION;
+            }
             chainemc[mclength] = 925; /* ECI */
             mclength++;
             chainemc[mclength] = symbol->eci - 810900;
@@ -1002,120 +1005,92 @@ INTERNAL int micro_pdf417(struct zint_symbol *symbol, unsigned char chaine[], in
 
     if (symbol->option_2 == 1) {
         /* the user specified 1 column and the data does fit */
-        variant = 6;
-        if (mclength <= 16) {
-            variant = 5;
-        }
-        if (mclength <= 12) {
-            variant = 4;
-        }
-        if (mclength <= 10) {
-            variant = 3;
-        }
-        if (mclength <= 7) {
-            variant = 2;
-        }
         if (mclength <= 4) {
             variant = 1;
+        } else if (mclength <= 7) {
+            variant = 2;
+        } else if (mclength <= 10) {
+            variant = 3;
+        } else if (mclength <= 12) {
+            variant = 4;
+        } else if (mclength <= 16) {
+            variant = 5;
+        } else {
+            variant = 6;
         }
-    }
-
-    if (symbol->option_2 == 2) {
+    } else if (symbol->option_2 == 2) {
         /* the user specified 2 columns and the data does fit */
-        variant = 13;
-        if (mclength <= 33) {
-            variant = 12;
-        }
-        if (mclength <= 29) {
-            variant = 11;
-        }
-        if (mclength <= 24) {
-            variant = 10;
-        }
-        if (mclength <= 19) {
-            variant = 9;
-        }
-        if (mclength <= 13) {
-            variant = 8;
-        }
         if (mclength <= 8) {
             variant = 7;
+        } else if (mclength <= 13) {
+            variant = 8;
+        } else if (mclength <= 19) {
+            variant = 9;
+        } else if (mclength <= 24) {
+            variant = 10;
+        } else if (mclength <= 29) {
+            variant = 11;
+        } else if (mclength <= 33) {
+            variant = 12;
+        } else {
+            variant = 13;
         }
-    }
-
-    if (symbol->option_2 == 3) {
+    } else if (symbol->option_2 == 3) {
         /* the user specified 3 columns and the data does fit */
-        variant = 23;
-        if (mclength <= 70) {
-            variant = 22;
-        }
-        if (mclength <= 58) {
-            variant = 21;
-        }
-        if (mclength <= 46) {
-            variant = 20;
-        }
-        if (mclength <= 34) {
-            variant = 19;
-        }
-        if (mclength <= 24) {
-            variant = 18;
-        }
-        if (mclength <= 18) {
-            variant = 17;
-        }
-        if (mclength <= 14) {
-            variant = 16;
-        }
-        if (mclength <= 10) {
-            variant = 15;
-        }
         if (mclength <= 6) {
             variant = 14;
+        } else if (mclength <= 10) {
+            variant = 15;
+        } else if (mclength <= 14) {
+            variant = 16;
+        } else if (mclength <= 18) {
+            variant = 17;
+        } else if (mclength <= 24) {
+            variant = 18;
+        } else if (mclength <= 34) {
+            variant = 19;
+        } else if (mclength <= 46) {
+            variant = 20;
+        } else if (mclength <= 58) {
+            variant = 21;
+        } else if (mclength <= 70) {
+            variant = 22;
+        } else {
+            variant = 23;
         }
-    }
-
-    if (symbol->option_2 == 4) {
+    } else if (symbol->option_2 == 4) {
         /* the user specified 4 columns and the data does fit */
-        variant = 34;
-        if (mclength <= 108) {
-            variant = 33;
-        }
-        if (mclength <= 90) {
-            variant = 32;
-        }
-        if (mclength <= 72) {
-            variant = 31;
-        }
-        if (mclength <= 54) {
-            variant = 30;
-        }
-        if (mclength <= 39) {
-            variant = 29;
-        }
-        if (mclength <= 30) {
-            variant = 28;
-        }
-        if (mclength <= 24) {
-            variant = 27;
-        }
-        if (mclength <= 18) {
-            variant = 26;
-        }
-        if (mclength <= 12) {
-            variant = 25;
-        }
         if (mclength <= 8) {
             variant = 24;
+        } else if (mclength <= 12) {
+            variant = 25;
+        } else if (mclength <= 18) {
+            variant = 26;
+        } else if (mclength <= 24) {
+            variant = 27;
+        } else if (mclength <= 30) {
+            variant = 28;
+        } else if (mclength <= 39) {
+            variant = 29;
+        } else if (mclength <= 54) {
+            variant = 30;
+        } else if (mclength <= 72) {
+            variant = 31;
+        } else if (mclength <= 90) {
+            variant = 32;
+        } else if (mclength <= 108) {
+            variant = 33;
+        } else {
+            variant = 34;
         }
-    }
-
-    if (variant == 0) {
+    } else {
         /* Zint can choose automatically from all available variations */
         for (i = 27; i >= 0; i--) {
 
             if (MicroAutosize[i] >= mclength) {
                 variant = MicroAutosize[i + 28];
+            } else {
+                break;
             }
         }
     }
@@ -1197,50 +1172,43 @@ INTERNAL int micro_pdf417(struct zint_symbol *symbol, unsigned char chaine[], in
     if (debug) printf("\nInternal row representation:\n");
     for (i = 0; i < symbol->rows; i++) {
         if (debug) printf("row %d: ", i);
-        strcpy(pattern, "");
+        bp = 0;
         offset = 929 * Cluster;
-        for (j = 0; j < 5; j++) {
-            dummy[j] = 0;
-        }
-        for (j = 0; j < symbol->option_2; j++) {
-            dummy[j + 1] = chainemc[i * symbol->option_2 + j];
-            if (debug) printf("[%d] ", dummy[j + 1]);
-        }
+        k = i * symbol->option_2;
 
         /* Copy the data into codebarre */
-        bin_append(rap_side[LeftRAP - 1], 10, pattern);
-        bin_append(pdf_bitpattern[offset + dummy[1]], 16, pattern);
-        strcat(pattern, "0");
-        if (symbol->option_2 == 3) {
-            bin_append(rap_centre[CentreRAP - 1], 10, pattern);
-        }
+        bp = bin_append_posn(rap_side[LeftRAP - 1], 10, pattern, bp);
+        bp = bin_append_posn(pdf_bitpattern[offset + chainemc[k]], 16, pattern, bp);
+        pattern[bp++] = '0';
         if (symbol->option_2 >= 2) {
-            bin_append(pdf_bitpattern[offset + dummy[2]], 16, pattern);
-            strcat(pattern, "0");
+            if (symbol->option_2 == 3) {
+                bp = bin_append_posn(rap_centre[CentreRAP - 1], 10, pattern, bp);
+            }
+            bp = bin_append_posn(pdf_bitpattern[offset + chainemc[k + 1]], 16, pattern, bp);
+            pattern[bp++] = '0';
+            if (symbol->option_2 >= 3) {
+                if (symbol->option_2 == 4) {
+                    bp = bin_append_posn(rap_centre[CentreRAP - 1], 10, pattern, bp);
+                }
+                bp = bin_append_posn(pdf_bitpattern[offset + chainemc[k + 2]], 16, pattern, bp);
+                pattern[bp++] = '0';
+                if (symbol->option_2 == 4) {
+                    bp = bin_append_posn(pdf_bitpattern[offset + chainemc[k + 3]], 16, pattern, bp);
+                    pattern[bp++] = '0';
+                }
+            }
         }
-        if (symbol->option_2 == 4) {
-            bin_append(rap_centre[CentreRAP - 1], 10, pattern);
-        }
-        if (symbol->option_2 >= 3) {
-            bin_append(pdf_bitpattern[offset + dummy[3]], 16, pattern);
-            strcat(pattern, "0");
-        }
-        if (symbol->option_2 == 4) {
-            bin_append(pdf_bitpattern[offset + dummy[4]], 16, pattern);
-            strcat(pattern, "0");
-        }
-        bin_append(rap_side[RightRAP - 1], 10, pattern);
-        strcat(pattern, "1"); /* stop */
-        if (debug) printf("%s\n", pattern);
+        bp = bin_append_posn(rap_side[RightRAP - 1], 10, pattern, bp);
+        pattern[bp++] = '1'; /* stop */
+        if (debug) printf("%.*s\n", bp, pattern);
 
         /* so now pattern[] holds the string of '1's and '0's. - copy this to the symbol */
-        for (loop = 0; loop < (int)strlen(pattern); loop++) {
+        for (loop = 0; loop < bp; loop++) {
             if (pattern[loop] == '1') {
                 set_module(symbol, i, loop);
             }
         }
         symbol->row_height[i] = 2;
-        symbol->width = strlen(pattern);
 
         /* Set up RAPs and Cluster for next row */
         LeftRAP++;
@@ -1261,6 +1229,7 @@ INTERNAL int micro_pdf417(struct zint_symbol *symbol, unsigned char chaine[], in
             Cluster = 0;
         }
     }
+    symbol->width = bp;
     
     /* Allow user to adjust height of symbol, but enforce minimum row height of 2X */
     calcheight = (int)(symbol->height / i);
diff --git a/backend/plessey.c b/backend/plessey.c
index dcc7eafa..caeecd45 100644
--- a/backend/plessey.c
+++ b/backend/plessey.c
@@ -37,9 +37,10 @@
 #define SSET    "0123456789ABCDEF"
 
 static const char *PlessTable[16] = {
-    "13131313", "31131313", "13311313", "31311313", "13133113", "31133113",
-    "13313113", "31313113", "13131331", "31131331", "13311331", "31311331", "13133131",
-    "31133131", "13313131", "31313131"
+    "13131313", "31131313", "13311313", "31311313",
+    "13133113", "31133113", "13313113", "31313113",
+    "13131331", "31131331", "13311331", "31311331",
+    "13133131", "31133131", "13313131", "31313131"
 };
 
 static const char *MSITable[10] = {
@@ -48,9 +49,9 @@ static const char *MSITable[10] = {
 };
 
 /* Not MSI/Plessey but the older Plessey standard */
-INTERNAL int plessey(struct zint_symbol *symbol, unsigned char source[], const size_t length) {
+INTERNAL int plessey(struct zint_symbol *symbol, unsigned char source[], int length) {
 
-    unsigned int i;
+    int i;
     unsigned char *checkptr;
     static const char grid[9] = {1, 1, 1, 1, 0, 1, 0, 0, 1};
     char dest[1024]; /* 8 + 65 * 8 + 8 * 2 + 9 + 1 ~ 1024 */
@@ -141,7 +142,7 @@ static int msi_plessey_mod10(struct zint_symbol *symbol, unsigned char source[],
 
     int i, wright, pump, n;
     unsigned long dau, pedwar;
-    char un[200], tri[32];
+    char un[32], tri[32];
     int error_number, h;
     char dest[1000];
 
@@ -174,7 +175,7 @@ static int msi_plessey_mod10(struct zint_symbol *symbol, unsigned char source[],
     sprintf(tri, "%lu", dau);
 
     pedwar = 0;
-    h = strlen(tri);
+    h = (int) strlen(tri);
     for (i = 0; i < h; i++) {
         pedwar += ctoi(tri[i]);
     }
@@ -208,7 +209,7 @@ static int msi_plessey_mod1010(struct zint_symbol *symbol, unsigned char source[
 
     int i, n, wright, pump;
     unsigned long dau, pedwar, chwech;
-    char un[16], tri[32];
+    char un[32], tri[32];
     int error_number, h;
     char dest[1000];
 
@@ -243,7 +244,7 @@ static int msi_plessey_mod1010(struct zint_symbol *symbol, unsigned char source[
     sprintf(tri, "%lu", dau);
 
     pedwar = 0;
-    h = strlen(tri);
+    h = (int) strlen(tri);
     for (i = 0; i < h; i++) {
         pedwar += ctoi(tri[i]);
     }
@@ -273,7 +274,7 @@ static int msi_plessey_mod1010(struct zint_symbol *symbol, unsigned char source[
     sprintf(tri, "%lu", dau);
 
     pedwar = 0;
-    h = strlen(tri);
+    h = (int) strlen(tri);
     for (i = 0; i < h; i++) {
         pedwar += ctoi(tri[i]);
     }
@@ -334,7 +335,7 @@ static int msi_plessey_mod11(struct zint_symbol *symbol, unsigned char source[],
     x = 0;
     weight = 2;
     for (i = src_len - 1; i >= 0; i--) {
-        x += weight * ctoi(source[i]);
+        x += (long) (weight * ctoi(source[i]));
         weight++;
         if (weight > 7) {
             weight = 2;
@@ -373,7 +374,7 @@ static int msi_plessey_mod1110(struct zint_symbol *symbol, unsigned char source[
     unsigned long x, dau, pedwar;
     int h;
     int si;
-    char un[16], tri[16];
+    char un[32], tri[32];
     int error_number;
     char dest[1000];
     unsigned char temp[32];
@@ -398,7 +399,7 @@ static int msi_plessey_mod1110(struct zint_symbol *symbol, unsigned char source[
     x = 0;
     weight = 2;
     for (si = src_len - 1; si >= 0; si--) {
-        x += weight * ctoi(source[si]);
+        x += (long) (weight * ctoi(source[si]));
         weight++;
         if (weight > 7) {
             weight = 2;
@@ -433,7 +434,7 @@ static int msi_plessey_mod1110(struct zint_symbol *symbol, unsigned char source[
     sprintf(tri, "%lu", dau);
 
     pedwar = 0;
-    h = strlen(tri);
+    h = (int) strlen(tri);
     for (i = 0; i < h; i++) {
         pedwar += ctoi(tri[i]);
     }
diff --git a/backend/sjis.c b/backend/sjis.c
index ccdf20be..4804379f 100644
--- a/backend/sjis.c
+++ b/backend/sjis.c
@@ -65,7 +65,7 @@ INTERNAL int utf_to_eci(const int eci, const unsigned char source[], unsigned ch
  * JISX0201.1976-0 (libiconv-1.16/lib/jisx0201.h)
  */
 
-static int jisx0201_wctomb(unsigned int *r, unsigned int wc) {
+static int jisx0201_wctomb(unsigned int *r, const unsigned int wc) {
     if (wc < 0x0080 && !(wc == 0x005c || wc == 0x007e)) {
         *r = wc;
         return 1;
@@ -1444,7 +1444,7 @@ static const Summary16 jisx0208_uni2indx_pageff[15] = {
   { 6877, 0x0000 }, { 6877, 0x0000 }, { 6877, 0x0028 },
 };
 
-static int jisx0208_wctomb(unsigned int *r, unsigned int wc) {
+static int jisx0208_wctomb(unsigned int *r, const unsigned int wc) {
     const Summary16 *summary = NULL;
     if (wc < 0x0100) {
         summary = &jisx0208_uni2indx_page00[(wc>>4)];
@@ -1484,7 +1484,7 @@ static int jisx0208_wctomb(unsigned int *r, unsigned int wc) {
  */
 
 /* Returns 1 or 2 on success, 0 if no mapping */
-INTERNAL int sjis_wctomb_zint(unsigned int *r, unsigned int wc) {
+INTERNAL int sjis_wctomb_zint(unsigned int *r, const unsigned int wc) {
     int ret;
 
     /* Try JIS X 0201-1976. */
@@ -1494,8 +1494,8 @@ INTERNAL int sjis_wctomb_zint(unsigned int *r, unsigned int wc) {
     }
 
     /* Try JIS X 0208-1990. */
-    /* ZINT: Note leaving mapping of full-width reverse solidus U+FF3C to 0x815F (duplicate of patched U+005C) to avoid
-     * having to regen tables */
+    /* ZINT: Note leaving mapping of full-width reverse solidus U+FF3C to 0x815F (duplicate of patched U+005C) to
+     * avoid having to regen tables */
     ret = jisx0208_wctomb(r, wc);
     if (ret) {
         return ret;
@@ -1503,7 +1503,7 @@ INTERNAL int sjis_wctomb_zint(unsigned int *r, unsigned int wc) {
 
     /* User-defined range. See
     * Ken Lunde's "CJKV Information Processing", table 4-66, p. 206. */
-    /* ZINT: https://file.allitebooks.com/20160708/CJKV%20Information%20Processing.pdf (table 4-86, p. 286, 2nd ed.) */
+    /* ZINT: https://file.allitebooks.com/20160708/CJKV%20Information%20Processing.pdf (table 4-86, p.286, 2nd ed.) */
     if (wc >= 0xe000 && wc < 0xe758) {
         unsigned char c1, c2;
         c1 = (unsigned int) (wc - 0xe000) / 188;
@@ -1517,7 +1517,7 @@ INTERNAL int sjis_wctomb_zint(unsigned int *r, unsigned int wc) {
 
 /* Convert UTF-8 string to Shift JIS and place in array of ints */
 INTERNAL int sjis_utf8tomb(struct zint_symbol *symbol, const unsigned char source[], int *p_length,
-            unsigned int *jisdata) {
+                unsigned int *jisdata) {
     int error_number;
     unsigned int i, length;
 #ifndef _MSC_VER
@@ -1542,8 +1542,8 @@ INTERNAL int sjis_utf8tomb(struct zint_symbol *symbol, const unsigned char sourc
 }
 
 /* Convert UTF-8 string to single byte ECI and place in array of ints */
-INTERNAL int sjis_utf8tosb(int eci, const unsigned char source[], int *p_length, unsigned int *jisdata,
-            int full_multibyte) {
+INTERNAL int sjis_utf8tosb(const int eci, const unsigned char source[], int *p_length, unsigned int *jisdata,
+                const int full_multibyte) {
     int error_number;
 #ifndef _MSC_VER
     unsigned char single_byte[*p_length + 1];
@@ -1562,9 +1562,9 @@ INTERNAL int sjis_utf8tosb(int eci, const unsigned char source[], int *p_length,
     return 0;
 }
 
-/* If `full_multibyte` set, copy byte input stream to array of ints, putting double-bytes that match QR Kanji mode in a
- * single entry. If `full_multibyte` not set, do a straight copy */
-INTERNAL void sjis_cpy(const unsigned char source[], int *p_length, unsigned int *jisdata, int full_multibyte) {
+/* If `full_multibyte` set, copy byte input stream to array of ints, putting double-bytes that match QR Kanji mode in
+ * a single entry. If `full_multibyte` not set, do a straight copy */
+INTERNAL void sjis_cpy(const unsigned char source[], int *p_length, unsigned int *jisdata, const int full_multibyte) {
     unsigned int i, j, jis, length;
     unsigned char c;
 
diff --git a/backend/sjis.h b/backend/sjis.h
index 4e237391..155b4c6d 100644
--- a/backend/sjis.h
+++ b/backend/sjis.h
@@ -37,12 +37,12 @@
 extern "C" {
 #endif /* __cplusplus */
 
-INTERNAL int sjis_wctomb_zint(unsigned int *r, unsigned int wc);
+INTERNAL int sjis_wctomb_zint(unsigned int *r, const unsigned int wc);
 INTERNAL int sjis_utf8tomb(struct zint_symbol *symbol, const unsigned char source[], int *p_length,
-            unsigned int *jisdata);
-INTERNAL int sjis_utf8tosb(int eci, const unsigned char source[], int *p_length, unsigned int *jisdata,
-            int full_multibyte);
-INTERNAL void sjis_cpy(const unsigned char source[], int *p_length, unsigned int *jisdata, int full_multibyte);
+                unsigned int *jisdata);
+INTERNAL int sjis_utf8tosb(const int eci, const unsigned char source[], int *p_length, unsigned int *jisdata,
+                const int full_multibyte);
+INTERNAL void sjis_cpy(const unsigned char source[], int *p_length, unsigned int *jisdata, const int full_multibyte);
 
 #ifdef __cplusplus
 }
diff --git a/backend/telepen.c b/backend/telepen.c
index 9db20b98..e6d26f16 100644
--- a/backend/telepen.c
+++ b/backend/telepen.c
@@ -31,7 +31,8 @@
  */
 /* vim: set ts=4 sw=4 et : */
 
-/* Telepen Barcode Symbology information and History (BSiH) https://telepen.co.uk/wp-content/uploads/2018/10/Barcode-Symbology-information-and-History.pdf */
+/* Telepen Barcode Symbology information and History (BSiH)
+   https://telepen.co.uk/wp-content/uploads/2018/10/Barcode-Symbology-information-and-History.pdf */
 
 #define SODIUM  "0123456789X"
 
@@ -57,8 +58,8 @@ static char *TeleTable[] = {
     "3113111113", "11311111111111", "331111111111", "111113111113", "31111111111111", "111311111113", "131111111113", "1111111111111111",
 };
 
-INTERNAL int telepen(struct zint_symbol *symbol, unsigned char source[], const size_t src_len) {
-    unsigned int i, count, check_digit;
+INTERNAL int telepen(struct zint_symbol *symbol, unsigned char source[], int src_len) {
+    int i, count, check_digit;
     int error_number;
     char dest[521]; /* 12 (start) + 30 * 16 (max for DELs) + 16 (check digit) + 12 (stop) + 1 = 521 */
 
@@ -104,39 +105,39 @@ INTERNAL int telepen(struct zint_symbol *symbol, unsigned char source[], const s
     return error_number;
 }
 
-INTERNAL int telepen_num(struct zint_symbol *symbol, unsigned char source[], const size_t src_len) {
-    unsigned int count, check_digit, glyph;
+INTERNAL int telepen_num(struct zint_symbol *symbol, unsigned char source[], int src_len) {
+    int count, check_digit, glyph;
     int error_number;
-    size_t i, temp_length = src_len;
+    int i;
     char dest[521]; /* 12 (start) + 30 * 16 (max for DELs) + 16 (check digit) + 12 (stop) + 1 = 521 */
     unsigned char temp[64];
 
     count = 0;
 
-    if (temp_length > 60) {
+    if (src_len > 60) {
         strcpy(symbol->errtxt, "392: Input too long");
         return ZINT_ERROR_TOO_LONG;
     }
     ustrcpy(temp, source);
     to_upper(temp);
-    error_number = is_sane(SODIUM, temp, temp_length);
+    error_number = is_sane(SODIUM, temp, src_len);
     if (error_number == ZINT_ERROR_INVALID_DATA) {
         strcpy(symbol->errtxt, "393: Invalid characters in data");
         return error_number;
     }
 
     /* Add a leading zero if required */
-    if (temp_length & 1) {
-        memmove(temp + 1, temp, temp_length);
+    if (src_len & 1) {
+        memmove(temp + 1, temp, src_len);
         temp[0] = '0';
 
-        temp[++temp_length] = '\0';
+        temp[++src_len] = '\0';
     }
 
     /* Start character */
     strcpy(dest, TeleTable['_']);
 
-    for (i = 0; i < temp_length; i += 2) {
+    for (i = 0; i < src_len; i += 2) {
         if (temp[i] == 'X') {
             strcpy(symbol->errtxt, "394: Invalid position of X in Telepen data");
             return ZINT_ERROR_INVALID_DATA;
diff --git a/backend/tests/test_2of5.c b/backend/tests/test_2of5.c
index 433bbdec..6b2ec8e7 100644
--- a/backend/tests/test_2of5.c
+++ b/backend/tests/test_2of5.c
@@ -48,8 +48,8 @@ static void test_large(int index, int debug) {
     struct item data[] = {
         /*  0*/ { BARCODE_C25STANDARD, "1", 80, 0, 1, 817 },
         /*  1*/ { BARCODE_C25STANDARD, "1", 81, ZINT_ERROR_TOO_LONG, -1, -1 },
-        /*  2*/ { BARCODE_C25INTER, "1", 89, 0, 1, 819 },
-        /*  3*/ { BARCODE_C25INTER, "1", 90, ZINT_ERROR_TOO_LONG, -1, -1 },
+        /*  2*/ { BARCODE_C25INTER, "1", 90, 0, 1, 819 },
+        /*  3*/ { BARCODE_C25INTER, "1", 91, ZINT_ERROR_TOO_LONG, -1, -1 },
         /*  4*/ { BARCODE_C25IATA, "1", 45, 0, 1, 639 },
         /*  5*/ { BARCODE_C25IATA, "1", 46, ZINT_ERROR_TOO_LONG, -1, -1 },
         /*  6*/ { BARCODE_C25LOGIC, "1", 80, 0, 1, 809 },
diff --git a/backend/tests/test_aztec.c b/backend/tests/test_aztec.c
index 76a46112..d9875ea4 100644
--- a/backend/tests/test_aztec.c
+++ b/backend/tests/test_aztec.c
@@ -2022,6 +2022,9 @@ static void test_perf(int index, int debug) {
                     "ABCDEFGHIJKLMNOPQRSTUVWXYZ abcdefghijklmnopqrstuvwxyz ~~~~~~~~~~~~~~~~~~~~~~~~~ ?????????????????????????? 12345678901234567890123456 \377\377\377\377\377\377"
                     "ABCDEFGHIJKLMNOPQRSTUVWXYZ abcdefghijklmnopqrstuvwxyz ~~~~~~~~~~~~~~~~~~~~~~~~~ ?????????????????????????? 12345678901234567890123456 \377\377\377\377\377\377",
                     0, 113, 113, "1540 chars, 12-bit words, mixed" },
+        /*  4*/ { BARCODE_AZRUNE, -1, -1, -1,
+                    "255",
+                    0, 11, 11, "3 chars, AZRUNE" },
     };
     int data_size = ARRAY_SIZE(data);
 
diff --git a/backend/tests/test_bmp.c b/backend/tests/test_bmp.c
index 046cacde..454f34de 100644
--- a/backend/tests/test_bmp.c
+++ b/backend/tests/test_bmp.c
@@ -32,7 +32,7 @@
 #include "testcommon.h"
 #include <sys/stat.h>
 
-extern int bmp_pixel_plot(struct zint_symbol *symbol, unsigned char *pixelbuf);
+INTERNAL int bmp_pixel_plot(struct zint_symbol *symbol, unsigned char *pixelbuf);
 
 static void test_pixel_plot(int index, int debug) {
 
diff --git a/backend/tests/test_code.c b/backend/tests/test_code.c
index e97c9adc..500b627f 100644
--- a/backend/tests/test_code.c
+++ b/backend/tests/test_code.c
@@ -68,8 +68,9 @@ static void test_large(int index, int debug) {
         /* 18*/ { BARCODE_VIN, -1, "1", 17, 0, 1, 246 },
         /* 19*/ { BARCODE_VIN, -1, "1", 18, ZINT_ERROR_TOO_LONG, -1, -1 },
         /* 20*/ { BARCODE_VIN, -1, "1", 16, ZINT_ERROR_TOO_LONG, -1, -1 },
-        /* 21*/ { BARCODE_HIBC_39, -1, "1", 66, 0, 1, 1119 }, // 68 - 2 ('+' and check digit)
-        /* 22*/ { BARCODE_HIBC_39, -1, "1", 67, ZINT_ERROR_TOO_LONG, -1, -1 },
+        /* 21*/ { BARCODE_VIN, 1, "1", 17, 0, 1, 259 },
+        /* 22*/ { BARCODE_HIBC_39, -1, "1", 66, 0, 1, 1119 }, // 68 - 2 ('+' and check digit)
+        /* 23*/ { BARCODE_HIBC_39, -1, "1", 67, ZINT_ERROR_TOO_LONG, -1, -1 },
     };
     int data_size = ARRAY_SIZE(data);
 
diff --git a/backend/tests/test_gif.c b/backend/tests/test_gif.c
index 3cd1a903..37d2c832 100644
--- a/backend/tests/test_gif.c
+++ b/backend/tests/test_gif.c
@@ -31,7 +31,7 @@
 
 #include "testcommon.h"
 
-extern int gif_pixel_plot(struct zint_symbol *symbol, unsigned char *pixelbuf);
+INTERNAL int gif_pixel_plot(struct zint_symbol *symbol, unsigned char *pixelbuf);
 
 static void test_pixel_plot(int index, int debug) {
 
diff --git a/backend/tests/test_plessey.c b/backend/tests/test_plessey.c
index a574a8de..e981a26b 100644
--- a/backend/tests/test_plessey.c
+++ b/backend/tests/test_plessey.c
@@ -189,6 +189,8 @@ static void test_encode(int index, int generate, int debug) {
 
     testStart("");
 
+    int do_bwipp = (debug & ZINT_DEBUG_TEST_BWIPP) && testUtilHaveGhostscript(); // Only do BWIPP test if asked, too slow otherwise
+
     int ret;
     struct item {
         int symbology;
@@ -202,34 +204,39 @@ static void test_encode(int index, int generate, int debug) {
         char *expected;
     };
     struct item data[] = {
-        /*  0*/ { BARCODE_MSI_PLESSEY, -1, "1234567890", 0, 1, 127, "Verified manually against bwipp and tec-it",
+        /*  0*/ { BARCODE_MSI_PLESSEY, -1, "1234567890", 0, 1, 127, "Verified manually against tec-it",
                     "1101001001001101001001101001001001101101001101001001001101001101001101101001001101101101101001001001101001001101001001001001001"
                 },
-        /*  1*/ { BARCODE_MSI_PLESSEY, 1, "1234567890", 0, 1, 139, "Verified manually against bwipp and tec-it",
+        /*  1*/ { BARCODE_MSI_PLESSEY, 1, "1234567890", 0, 1, 139, "Verified manually against tec-it",
                     "1101001001001101001001101001001001101101001101001001001101001101001101101001001101101101101001001001101001001101001001001001001001101101001"
                 },
-        /*  2*/ { BARCODE_MSI_PLESSEY, 2, "1234567890", 0, 1, 151, "Verified manually against bwipp and tec-it",
+        /*  2*/ { BARCODE_MSI_PLESSEY, 2, "1234567890", 0, 1, 151, "Verified manually against tec-it",
                     "1101001001001101001001101001001001101101001101001001001101001101001101101001001101101101101001001001101001001101001001001001001001101101001001001101001"
                 },
-        /*  3*/ { BARCODE_MSI_PLESSEY, 3, "1234567890", 0, 1, 139, "Verified manually against bwipp",
+        /*  3*/ { BARCODE_MSI_PLESSEY, 3, "1234567890", 0, 1, 139, "",
                     "1101001001001101001001101001001001101101001101001001001101001101001101101001001101101101101001001001101001001101001001001001001001101101001"
                 },
-        /*  4*/ { BARCODE_MSI_PLESSEY, 4, "1234567890", 0, 1, 151, "Verified manually against bwipp",
+        /*  4*/ { BARCODE_MSI_PLESSEY, 4, "1234567890", 0, 1, 151, "",
                     "1101001001001101001001101001001001101101001101001001001101001101001101101001001101101101101001001001101001001101001001001001001001101101001001001101001"
                 },
-        /*  5*/ { BARCODE_MSI_PLESSEY, 3, "2211", 0, 1, 79, "Produces mod-11 '10' check digit; verified manually against bwipp (badmod11)",
+        /*  5*/ { BARCODE_MSI_PLESSEY, 3, "2211", 0, 1, 79, "Produces mod-11 '10' check digit; BWIPP (badmod11)",
                     "1101001001101001001001101001001001001101001001001101001001001101001001001001001"
                 },
-        /*  6*/ { BARCODE_MSI_PLESSEY, 4, "2211", 0, 1, 91, "Verified manually against bwipp (badmod11)",
+        /*  6*/ { BARCODE_MSI_PLESSEY, 4, "2211", 0, 1, 91, "BWIPP (badmod11)",
                     "1101001001101001001001101001001001001101001001001101001001001101001001001001001001001001001"
                 },
-        /*  7*/ { BARCODE_PLESSEY, -1, "0123456789ABCDEF", 0, 1, 323, "Verified manually against bwipp",
+        /*  7*/ { BARCODE_PLESSEY, -1, "0123456789ABCDEF", 0, 1, 323, "",
                     "11101110100011101000100010001000111010001000100010001110100010001110111010001000100010001110100011101000111010001000111011101000111011101110100010001000100011101110100010001110100011101000111011101110100011101000100011101110111010001110111010001110111011101110111011101110111010001000111010001000100010001110001000101110111"
                 },
+        /*  8*/ { BARCODE_MSI_PLESSEY, 4, "999999999999999999", 0, 1, 247, "Max value; #209 check buffer not overrun",
+                    "1101101001001101101001001101101001001101101001001101101001001101101001001101101001001101101001001101101001001101101001001101101001001101101001001101101001001101101001001101101001001101101001001101101001001101101001001101101001001001001001001101001"
+                },
     };
     int data_size = ARRAY_SIZE(data);
 
     char escaped[1024];
+    char bwipp_buf[4096];
+    char bwipp_msg[1024];
 
     for (int i = 0; i < data_size; i++) {
 
@@ -254,10 +261,17 @@ static void test_encode(int index, int generate, int debug) {
                 assert_equal(symbol->rows, data[i].expected_rows, "i:%d symbol->rows %d != %d (%s)\n", i, symbol->rows, data[i].expected_rows, data[i].data);
                 assert_equal(symbol->width, data[i].expected_width, "i:%d symbol->width %d != %d (%s)\n", i, symbol->width, data[i].expected_width, data[i].data);
 
-                if (ret == 0) {
-                    int width, row;
-                    ret = testUtilModulesCmp(symbol, data[i].expected, &width, &row);
-                    assert_zero(ret, "i:%d testUtilModulesCmp ret %d != 0 width %d row %d (%s)\n", i, ret, width, row, data[i].data);
+                int width, row;
+                ret = testUtilModulesCmp(symbol, data[i].expected, &width, &row);
+                assert_zero(ret, "i:%d testUtilModulesCmp ret %d != 0 width %d row %d (%s)\n", i, ret, width, row, data[i].data);
+
+                if (do_bwipp && testUtilCanBwipp(i, symbol, -1, data[i].option_2, -1, debug)) {
+                    ret = testUtilBwipp(i, symbol, -1, data[i].option_2, -1, data[i].data, length, NULL, bwipp_buf, sizeof(bwipp_buf));
+                    assert_zero(ret, "i:%d %s testUtilBwipp ret %d != 0\n", i, testUtilBarcodeName(symbol->symbology), ret);
+
+                    ret = testUtilBwippCmp(symbol, bwipp_msg, bwipp_buf, data[i].expected);
+                    assert_zero(ret, "i:%d %s testUtilBwippCmp %d != 0 %s\n  actual: %s\nexpected: %s\n",
+                                   i, testUtilBarcodeName(symbol->symbology), ret, bwipp_msg, bwipp_buf, data[i].expected);
                 }
             }
         }
diff --git a/backend/tests/test_png.c b/backend/tests/test_png.c
index 62deab6a..66ee1570 100644
--- a/backend/tests/test_png.c
+++ b/backend/tests/test_png.c
@@ -32,7 +32,7 @@
 #include "testcommon.h"
 #include <sys/stat.h>
 
-extern int png_pixel_plot(struct zint_symbol *symbol, unsigned char *pixelbuf);
+INTERNAL int png_pixel_plot(struct zint_symbol *symbol, unsigned char *pixelbuf);
 
 static void test_pixel_plot(int index, int debug) {
 
diff --git a/backend/tests/test_qr.c b/backend/tests/test_qr.c
index cca27946..96296ca7 100644
--- a/backend/tests/test_qr.c
+++ b/backend/tests/test_qr.c
@@ -2025,6 +2025,74 @@ static void test_microqr_encode(int index, int generate, int debug) {
     testFinish();
 }
 
+// Not a real test, just performance indicator
+static void test_microqr_perf(int index, int debug) {
+
+    if (!(debug & ZINT_DEBUG_TEST_PERFORMANCE)) { /* -d 256 */
+        return;
+    }
+
+    int ret;
+    struct item {
+        int symbology;
+        int input_mode;
+        int option_1;
+        int option_2;
+        char *data;
+        int ret;
+
+        int expected_rows;
+        int expected_width;
+        char *comment;
+    };
+    struct item data[] = {
+        /*  0*/ { BARCODE_MICROQR, UNICODE_MODE, 1, 1, "12345", 0, 11, 11, "Max 5 numbers, M1" },
+        /*  1*/ { BARCODE_MICROQR, UNICODE_MODE, 1, 2, "1234567890", 0, 13, 13, "Max 10 numbers, M2-L" },
+        /*  2*/ { BARCODE_MICROQR, UNICODE_MODE, 1, 3, "123456789012345", 0, 15, 15, "Max 15 numbers, M3-L" },
+        /*  3*/ { BARCODE_MICROQR, UNICODE_MODE, 1, 4, "12345678901234567890123456789012345", 0, 17, 17, "Max 35 numbers, M4-L" },
+    };
+    int data_size = ARRAY_SIZE(data);
+
+    clock_t start, total_encode = 0, total_buffer = 0, diff_encode, diff_buffer;
+
+    for (int i = 0; i < data_size; i++) {
+
+        if (index != -1 && i != index) continue;
+
+        diff_encode = diff_buffer = 0;
+
+        for (int j = 0; j < TEST_PERF_ITERATIONS; j++) {
+            struct zint_symbol *symbol = ZBarcode_Create();
+            assert_nonnull(symbol, "Symbol not created\n");
+
+            int length = testUtilSetSymbol(symbol, data[i].symbology, data[i].input_mode, -1 /*eci*/, data[i].option_1, data[i].option_2, -1, -1 /*output_options*/, data[i].data, -1, debug);
+
+            start = clock();
+            ret = ZBarcode_Encode(symbol, (unsigned char *) data[i].data, length);
+            diff_encode += clock() - start;
+            assert_equal(ret, data[i].ret, "i:%d ZBarcode_Encode ret %d != %d (%s)\n", i, ret, data[i].ret, symbol->errtxt);
+
+            assert_equal(symbol->rows, data[i].expected_rows, "i:%d symbol->rows %d != %d (%s)\n", i, symbol->rows, data[i].expected_rows, data[i].data);
+            assert_equal(symbol->width, data[i].expected_width, "i:%d symbol->width %d != %d (%s)\n", i, symbol->width, data[i].expected_width, data[i].data);
+
+            start = clock();
+            ret = ZBarcode_Buffer(symbol, 0 /*rotate_angle*/);
+            diff_buffer += clock() - start;
+            assert_zero(ret, "i:%d ZBarcode_Buffer ret %d != 0 (%s)\n", i, ret, symbol->errtxt);
+
+            ZBarcode_Delete(symbol);
+        }
+
+        printf("%s: diff_encode %gms, diff_buffer %gms\n", data[i].comment, diff_encode * 1000.0 / CLOCKS_PER_SEC, diff_buffer * 1000.0 / CLOCKS_PER_SEC);
+
+        total_encode += diff_encode;
+        total_buffer += diff_buffer;
+    }
+    if (index != -1) {
+        printf("totals: encode %gms, buffer %gms\n", total_encode * 1000.0 / CLOCKS_PER_SEC, total_buffer * 1000.0 / CLOCKS_PER_SEC);
+    }
+}
+
 static void test_upnqr_input(int index, int generate, int debug) {
 
     testStart("");
@@ -2674,6 +2742,7 @@ int main(int argc, char *argv[]) {
         { "test_microqr_padding", test_microqr_padding, 1, 1, 1 },
         { "test_microqr_optimize", test_microqr_optimize, 1, 1, 1 },
         { "test_microqr_encode", test_microqr_encode, 1, 1, 1 },
+        { "test_microqr_perf", test_microqr_perf, 1, 0, 1 },
 
         { "test_upnqr_input", test_upnqr_input, 1, 1, 1 },
         { "test_upnqr_encode", test_upnqr_encode, 1, 1, 1 },
diff --git a/backend/tests/test_tif.c b/backend/tests/test_tif.c
index 6ae51a2c..c07b0225 100644
--- a/backend/tests/test_tif.c
+++ b/backend/tests/test_tif.c
@@ -31,7 +31,7 @@
 
 #include "testcommon.h"
 
-extern int tif_pixel_plot(struct zint_symbol *symbol, unsigned char *pixelbuf);
+INTERNAL int tif_pixel_plot(struct zint_symbol *symbol, unsigned char *pixelbuf);
 
 // For overview when debugging: ./test_tiff -f pixel_plot -d 5
 static void test_pixel_plot(int index, int debug) {
diff --git a/backend/tests/tools/run_bwipp_tests.sh b/backend/tests/tools/run_bwipp_tests.sh
index 04c34b69..b94f288f 100755
--- a/backend/tests/tools/run_bwipp_tests.sh
+++ b/backend/tests/tools/run_bwipp_tests.sh
@@ -29,6 +29,7 @@ run_bwipp_test "test_gs1" "gs1_reduce"
 run_bwipp_test "test_imail" "encode"
 run_bwipp_test "test_medical" "encode"
 run_bwipp_test "test_pdf417" "encode"
+run_bwipp_test "test_plessey" "encode"
 run_bwipp_test "test_postal" "encode"
 run_bwipp_test "test_rss"
 run_bwipp_test "test_telepen" "encode"
diff --git a/backend/ultra.c b/backend/ultra.c
index e3e9c3fb..eaf0fa3d 100644
--- a/backend/ultra.c
+++ b/backend/ultra.c
@@ -351,8 +351,9 @@ static float look_ahead_ascii(unsigned char source[], int in_length, int in_locn
 }
 
 /* Returns true if should latch to subset other than given `subset` */
-static int c43_should_latch_other(const unsigned char data[], const size_t length, const unsigned int locn, int subset, int gs1) {
-    unsigned int i, fraglen, predict_window;
+static int c43_should_latch_other(const unsigned char data[], const int length, const int locn, const int subset,
+            const int gs1) {
+    int i, fraglen, predict_window;
     int cnt, alt_cnt, fragno;
     const char* set = subset == 1 ? ultra_c43_set1 : ultra_c43_set2;
     const char* alt_set = subset == 2 ? ultra_c43_set1 : ultra_c43_set2;
@@ -612,7 +613,8 @@ static float look_ahead_c43(unsigned char source[], int in_length, int in_locn,
 }
 
 /* Produces a set of codewords which are "somewhat" optimised - this could be improved on */
-static int ultra_generate_codewords(struct zint_symbol *symbol, const unsigned char source[], const size_t in_length, int codewords[]) {
+static int ultra_generate_codewords(struct zint_symbol *symbol, const unsigned char source[], const int in_length,
+            int codewords[]) {
     int i;
     int crop_length;
     int codeword_count = 0;
@@ -646,7 +648,7 @@ static int ultra_generate_codewords(struct zint_symbol *symbol, const unsigned c
 
     // Decide start character codeword (from Table 5)
     symbol_mode = ASCII_MODE;
-    for (i = 0; i < (int) in_length; i++) {
+    for (i = 0; i < in_length; i++) {
         if (source[i] >= 0x80) {
             symbol_mode = EIGHTBIT_MODE;
             break;
@@ -747,14 +749,14 @@ static int ultra_generate_codewords(struct zint_symbol *symbol, const unsigned c
             }
             codeword_count++;
 
-            for (i = 7; i < ((int) in_length - 2); i++) {
+            for (i = 7; i < (in_length - 2); i++) {
                 crop_source[i - 7] = source[i];
             }
             crop_length = in_length - 9;
             crop_source[crop_length] = '\0';
    } else {
         /* Make a cropped version of input data - removes http:// and https:// if needed */
-        for (i = input_locn; i < (int) in_length; i++) {
+        for (i = input_locn; i < in_length; i++) {
             crop_source[i - input_locn] = source[i];
         }
         crop_length = in_length - input_locn;
@@ -860,7 +862,7 @@ static int ultra_generate_codewords(struct zint_symbol *symbol, const unsigned c
     return codeword_count;
 }
 
-INTERNAL int ultracode(struct zint_symbol *symbol, const unsigned char source[], const size_t in_length) {
+INTERNAL int ultracode(struct zint_symbol *symbol, unsigned char source[], int length) {
     int data_cw_count = 0;
     int acc, qcc;
     int ecc_level;
@@ -879,7 +881,7 @@ INTERNAL int ultracode(struct zint_symbol *symbol, const unsigned char source[],
     char* pattern;
 #endif /* _MSC_VER */
 
-    cw_memalloc = in_length * 2;
+    cw_memalloc = length * 2;
     if (cw_memalloc < 283) {
         cw_memalloc = 283;
     }
@@ -895,7 +897,7 @@ INTERNAL int ultracode(struct zint_symbol *symbol, const unsigned char source[],
     data_codewords = (int *) _alloca(cw_memalloc * sizeof (int));
 #endif /* _MSC_VER */
 
-    data_cw_count = ultra_generate_codewords(symbol, source, in_length, data_codewords);
+    data_cw_count = ultra_generate_codewords(symbol, source, length, data_codewords);
 
     if (symbol->debug & ZINT_DEBUG_PRINT) {
         printf("Codewords returned = %d\n", data_cw_count);
diff --git a/frontend/main.c b/frontend/main.c
index 7dc418af..4b998c5a 100644
--- a/frontend/main.c
+++ b/frontend/main.c
@@ -299,7 +299,7 @@ static int batch_process(struct zint_symbol *symbol, char *filename, int mirror_
     FILE *file;
     unsigned char buffer[ZINT_MAX_DATA_LEN] = {0}; // Maximum HanXin input
     unsigned char character = 0;
-    int posn = 0, error_number = 0, line_count = 1;
+    int buf_posn = 0, error_number = 0, line_count = 1;
     char output_file[256];
     char number[12], reverse_number[12];
     int inpos, local_line_count;
@@ -333,10 +333,10 @@ static int batch_process(struct zint_symbol *symbol, char *filename, int mirror_
         }
         character = (unsigned char) intChar;
         if (character == '\n') {
-            if (posn > 0 && buffer[posn - 1] == '\r') {
+            if (buf_posn > 0 && buffer[buf_posn - 1] == '\r') {
                 /* CR+LF - assume Windows formatting and remove CR */
-                posn--;
-                buffer[posn] = '\0';
+                buf_posn--;
+                buffer[buf_posn] = '\0';
             }
 
             if (mirror_mode == 0) {
@@ -433,7 +433,7 @@ static int batch_process(struct zint_symbol *symbol, char *filename, int mirror_
                     }
                     i++;
                     o++;
-                } while (i < posn && o < 251);
+                } while (i < buf_posn && o < 251);
 
                 /* Add file extension */
                 output_file[o] = '.';
@@ -443,20 +443,20 @@ static int batch_process(struct zint_symbol *symbol, char *filename, int mirror_
             }
 
             strcpy(symbol->outfile, output_file);
-            error_number = ZBarcode_Encode_and_Print(symbol, buffer, posn, rotate_angle);
+            error_number = ZBarcode_Encode_and_Print(symbol, buffer, buf_posn, rotate_angle);
             if (error_number != 0) {
                 fprintf(stderr, "On line %d: %s\n", line_count, symbol->errtxt);
                 fflush(stderr);
             }
             ZBarcode_Clear(symbol);
             memset(buffer, 0, sizeof(buffer));
-            posn = 0;
+            buf_posn = 0;
             line_count++;
         } else {
-            buffer[posn] = character;
-            posn++;
+            buffer[buf_posn] = character;
+            buf_posn++;
         }
-        if (posn >= (int) sizeof(buffer)) {
+        if (buf_posn >= (int) sizeof(buffer)) {
             fprintf(stderr, "On line %d: Error 103: Input data too long\n", line_count);
             fflush(stderr);
             do {