diff --git a/backend/codablock.c b/backend/codablock.c
index 4ce91ba6..625096ab 100644
--- a/backend/codablock.c
+++ b/backend/codablock.c
@@ -640,7 +640,7 @@ INTERNAL int codablock(struct zint_symbol *symbol, unsigned char source[], int l
     int emptyColumns;
     char dest[1000];
     int r, c;
-    float min_row_height;
+    float min_row_height = 0.0f;
 #ifdef _MSC_VER
     CharacterSetTable *T;
     unsigned char *data;
@@ -997,8 +997,7 @@ INTERNAL int codablock(struct zint_symbol *symbol, unsigned char source[], int l
     error_number = set_height(symbol, min_row_height, (min_row_height > 10.0f ? min_row_height : 10.0f) * rows, 0.0f,
                                 0 /*no_errtxt*/);
 #else
-    (void)min_row_height;
-    (void) set_height(symbol, 0.0f, 10.0f * rows, 0.0f, 1 /*no_errtxt*/);
+    (void) set_height(symbol, min_row_height, 10.0f * rows, 0.0f, 1 /*no_errtxt*/);
 #endif
 
     symbol->output_options |= BARCODE_BIND;
diff --git a/backend/code1.c b/backend/code1.c
index 2cb32d02..f590a4b1 100644
--- a/backend/code1.c
+++ b/backend/code1.c
@@ -861,7 +861,7 @@ static int c1_encode(struct zint_symbol *symbol, unsigned char source[], unsigne
                 db_p = bin_append_posn(1, 2, decimal_binary, db_p);
             }
 
-            (void)decimal_binary_transfer(decimal_binary, db_p, target, &tp);
+            (void) decimal_binary_transfer(decimal_binary, db_p, target, &tp);
         }
         current_mode = C1_ASCII;
 
diff --git a/backend/code16k.c b/backend/code16k.c
index 41e3c133..acc5597c 100644
--- a/backend/code16k.c
+++ b/backend/code16k.c
@@ -120,7 +120,7 @@ INTERNAL int code16k(struct zint_symbol *symbol, unsigned char source[], int len
     int input_length;
     int gs1, c_count;
     int separator;
-    float min_row_height;
+    float min_row_height = 0.0f;
 
     /* Suppresses clang-analyzer-core.UndefinedBinaryOperatorResult warning on fset which is fully set */
     assert(length > 0);
@@ -500,8 +500,8 @@ INTERNAL int code16k(struct zint_symbol *symbol, unsigned char source[], int len
     error_number = set_height(symbol, min_row_height, (min_row_height > 10.0f ? min_row_height : 10.0f) * rows, 0.0f,
                                 0 /*no_errtxt*/);
 #else
-    (void)min_row_height; (void)separator;
-    (void) set_height(symbol, 0.0f, 10.0f * rows, 0.0f, 1 /*no_errtxt*/);
+    (void)&separator;
+    (void) set_height(symbol, min_row_height, 10.0f * rows, 0.0f, 1 /*no_errtxt*/);
 #endif
 
     symbol->output_options |= BARCODE_BIND;
diff --git a/backend/code49.c b/backend/code49.c
index 3fec358c..e009ab8a 100644
--- a/backend/code49.c
+++ b/backend/code49.c
@@ -50,7 +50,7 @@ INTERNAL int code_49(struct zint_symbol *symbol, unsigned char source[], int len
     int gs1;
     int h, len;
     int separator;
-    float min_row_height;
+    float min_row_height = 0.0f;
     int error_number = 0;
 
     if (length > 81) {
@@ -358,8 +358,8 @@ INTERNAL int code_49(struct zint_symbol *symbol, unsigned char source[], int len
     error_number = set_height(symbol, min_row_height, (min_row_height > 10.0f ? min_row_height : 10.0f) * rows, 0.0f,
                                 0 /*no_errtxt*/);
 #else
-    (void)min_row_height; (void)separator;
-    (void) set_height(symbol, 0.0f, 10.0f * rows, 0.0f, 1 /*no_errtxt*/);
+    (void)&separator;
+    (void) set_height(symbol, min_row_height, 10.0f * rows, 0.0f, 1 /*no_errtxt*/);
 #endif
 
     symbol->output_options |= BARCODE_BIND;
diff --git a/backend/common.h b/backend/common.h
index 0856364a..ab826f40 100644
--- a/backend/common.h
+++ b/backend/common.h
@@ -64,6 +64,9 @@
 #    define ceilf (float) ceil
 #    define floorf (float) floor
 #    define roundf(arg) ((float) floor((arg) + 0.5f))
+#    if _MSC_VER == 1200 /* VC6 */
+#      define round(arg) floor((arg) + 0.5f)
+#    endif
 #  endif
 #  pragma warning(disable: 4244) /* conversion from int to float */
 #  if _MSC_VER >= 1900 /* MSVC 2015 */
diff --git a/backend/library.c b/backend/library.c
index a8ee2145..bbb1c243 100644
--- a/backend/library.c
+++ b/backend/library.c
@@ -1243,7 +1243,7 @@ int ZBarcode_Encode(struct zint_symbol *symbol, const unsigned char *source, int
     if (error_number == 0) {
         error_number = warn_number;
     }
-    (void)error_tag(symbol->errtxt, error_number);
+    (void) error_tag(symbol->errtxt, error_number);
 
     if (error_number < ZINT_ERROR) {
         if (symbol->height < 0.5f) { /* Absolute minimum */
diff --git a/backend/output.c b/backend/output.c
index ebf4bf66..b24f9afd 100644
--- a/backend/output.c
+++ b/backend/output.c
@@ -555,7 +555,7 @@ INTERNAL float output_large_bar_height(struct zint_symbol *symbol, int si) {
             symbol->height = large_bar_height * zero_count + fixed_height;
         }
         if (si && large_bar_height * si != (int) (large_bar_height * si)) {
-            large_bar_height = (float) (round(large_bar_height * si) / si);
+            large_bar_height = roundf(large_bar_height * si) / si;
             symbol->height = large_bar_height * zero_count + fixed_height;
         }
         /* Note should never happen that have both zero_count and round_rows */
@@ -565,7 +565,7 @@ INTERNAL float output_large_bar_height(struct zint_symbol *symbol, int si) {
             fixed_height = 0.0f;
             for (i = 0; i < symbol->rows; i++) {
                 if (symbol->row_height[i] * si != (int) (symbol->row_height[i] * si)) {
-                    symbol->row_height[i] = (float) (round(symbol->row_height[i] * si) / si);
+                    symbol->row_height[i] = roundf(symbol->row_height[i] * si) / si;
                 }
                 fixed_height += symbol->row_height[i];
             }
diff --git a/backend/vector.c b/backend/vector.c
index bf267850..2e230c7e 100644
--- a/backend/vector.c
+++ b/backend/vector.c
@@ -35,10 +35,6 @@
 
 #ifdef _MSC_VER
 #include <malloc.h>
-/* For Visual C++ 6 suppress conversion from int to float warning */
-#if _MSC_VER == 1200
-#pragma warning(disable: 4244)
-#endif
 #endif
 
 #include "common.h"