activate -Wcast-qual and fix warnings

amalgamate.sh

@@ -23,20 +23,22 @@ do
 	sed -i "s/#include \"$i.h\"//g" $OUTPUT_PREFIX.c
 done
 
+WARNINGS="-Wall -Wcast-qual"
+
 echo "int main() { return 0; }" > main.c
 echo "Test compile with GCC..."
-gcc -pedantic -Wall main.c $OUTPUT_PREFIX.c -o test.out
+gcc -pedantic $WARNINGS main.c $OUTPUT_PREFIX.c -o test.out
 echo "Test compile with GCC ANSI..."
-gcc -ansi -pedantic -Wall main.c $OUTPUT_PREFIX.c -o test.out
+gcc -ansi -pedantic $WARNINGS main.c $OUTPUT_PREFIX.c -o test.out
 if command -v clang
 then
 		echo "Test compile with clang..."
-        clang -Wall -Wpedantic -fsanitize=unsigned-integer-overflow main.c $OUTPUT_PREFIX.c -o test.out
+        clang $WARNINGS -Wpedantic -fsanitize=unsigned-integer-overflow main.c $OUTPUT_PREFIX.c -o test.out
 fi
 for def in MINIZ_NO_STDIO MINIZ_NO_TIME MINIZ_NO_ARCHIVE_APIS MINIZ_NO_ARCHIVE_WRITING_APIS MINIZ_NO_ZLIB_APIS MINIZ_NO_ZLIB_COMPATIBLE_NAMES MINIZ_NO_MALLOC
 do
 	echo "Test compile with GCC and define $def..."
-	gcc -ansi -pedantic -Wall main.c $OUTPUT_PREFIX.c -o test.out -D${def}
+	gcc -ansi -pedantic $WARNINGS main.c $OUTPUT_PREFIX.c -o test.out -D${def}
 done
 rm test.out
 rm main.c
@@ -65,5 +67,3 @@ EOF
 cd ..
 
 echo "Amalgamation created."
-
-

miniz_tdef.c

@@ -1498,7 +1498,7 @@ void *tdefl_write_image_to_png_file_in_memory_ex(const void *pImage, int w, int
     for (y = 0; y < h; ++y)
     {
         tdefl_compress_buffer(pComp, &z, 1, TDEFL_NO_FLUSH);
-        tdefl_compress_buffer(pComp, (mz_uint8 *)pImage + (flip ? (h - 1 - y) : y) * bpl, bpl, TDEFL_NO_FLUSH);
+        tdefl_compress_buffer(pComp, (const mz_uint8 *)pImage + (flip ? (h - 1 - y) : y) * bpl, bpl, TDEFL_NO_FLUSH);
     }
     if (tdefl_compress_buffer(pComp, NULL, 0, TDEFL_FINISH) != TDEFL_STATUS_DONE)
     {

miniz_zip.c

@@ -929,6 +929,11 @@ static size_t mz_zip_mem_read_func(void *pOpaque, mz_uint64 file_ofs, void *pBuf
 
 mz_bool mz_zip_reader_init_mem(mz_zip_archive *pZip, const void *pMem, size_t size, mz_uint flags)
 {
+    union {
+        void* pMut;
+        const void* pConst;
+    } ptr_const_cast;
+
     if (!pMem)
         return mz_zip_set_error(pZip, MZ_ZIP_INVALID_PARAMETER);
 
@@ -944,11 +949,8 @@ mz_bool mz_zip_reader_init_mem(mz_zip_archive *pZip, const void *pMem, size_t si
     pZip->m_pIO_opaque = pZip;
     pZip->m_pNeeds_keepalive = NULL;
 
-#ifdef __cplusplus
+    ptr_const_cast.pConst = pMem;
-    pZip->m_pState->m_pMem = const_cast<void *>(pMem);
+    pZip->m_pState->m_pMem = ptr_const_cast.pMut;
-#else
-    pZip->m_pState->m_pMem = (void *)pMem;
-#endif
 
     pZip->m_pState->m_mem_size = size;
 
@@ -3239,8 +3241,8 @@ mz_bool mz_zip_writer_add_mem_ex_v2(mz_zip_archive *pZip, const char *pArchive_n
     if (!pState->m_zip64)
     {
         /* Bail early if the archive would obviously become too large */
-        if ((pZip->m_archive_size + num_alignment_padding_bytes + MZ_ZIP_LOCAL_DIR_HEADER_SIZE + archive_name_size 
+        if ((pZip->m_archive_size + num_alignment_padding_bytes + MZ_ZIP_LOCAL_DIR_HEADER_SIZE + archive_name_size
-			+ MZ_ZIP_CENTRAL_DIR_HEADER_SIZE + archive_name_size + comment_size + user_extra_data_len + 
+			+ MZ_ZIP_CENTRAL_DIR_HEADER_SIZE + archive_name_size + comment_size + user_extra_data_len +
 			pState->m_central_dir.m_size + MZ_ZIP_END_OF_CENTRAL_DIR_HEADER_SIZE + user_extra_data_central_len
 			+ MZ_ZIP_DATA_DESCRIPTER_SIZE32) > 0xFFFFFFFF)
         {
@@ -3498,7 +3500,7 @@ mz_bool mz_zip_writer_add_read_buf_callback(mz_zip_archive *pZip, const char *pA
     if (!pState->m_zip64)
     {
         /* Bail early if the archive would obviously become too large */
-        if ((pZip->m_archive_size + num_alignment_padding_bytes + MZ_ZIP_LOCAL_DIR_HEADER_SIZE + archive_name_size + MZ_ZIP_CENTRAL_DIR_HEADER_SIZE 
+        if ((pZip->m_archive_size + num_alignment_padding_bytes + MZ_ZIP_LOCAL_DIR_HEADER_SIZE + archive_name_size + MZ_ZIP_CENTRAL_DIR_HEADER_SIZE
 			+ archive_name_size + comment_size + user_extra_data_len + pState->m_central_dir.m_size + MZ_ZIP_END_OF_CENTRAL_DIR_HEADER_SIZE + 1024
 			+ MZ_ZIP_DATA_DESCRIPTER_SIZE32 + user_extra_data_central_len) > 0xFFFFFFFF)
         {