diff --git a/backend/CMakeLists.txt b/backend/CMakeLists.txt
index 612e1158..72637e61 100644
--- a/backend/CMakeLists.txt
+++ b/backend/CMakeLists.txt
@@ -22,6 +22,7 @@ set_target_properties(zint PROPERTIES 	SOVERSION "${ZINT_VERSION_MAJOR}.${ZINT_V
 					VERSION ${ZINT_VERSION})
 
 target_link_libraries(zint ${PNG_LIBRARIES} )
+target_link_libraries(zint -lm)
 
 install(TARGETS zint  ${INSTALL_TARGETS_DEFAULT_ARGS} )
 install(FILES zint.h DESTINATION ${INCLUDE_INSTALL_DIR} COMPONENT Devel)
diff --git a/backend/png.c b/backend/png.c
index c3a69361..7c53290f 100644
--- a/backend/png.c
+++ b/backend/png.c
@@ -34,8 +34,8 @@
 
 #ifndef NO_PNG
 #include "png.h"        /* libpng header; includes zlib.h and setjmp.h */
-#include "maxipng.h"	/* Maxicode shapes */
 #endif /* NO_PNG */
+#include "maxipng.h"	/* Maxicode shapes */
 
 #include "font.h"	/* Font for human readable text */