Png.c: In function ‘PngWriteData’:
Png.c:603:38: warning: declaration of ‘png_ptr’ shadows a global declaration [-Wshadow]
  603 | static void PngWriteData(png_structp png_ptr, png_bytep data, png_size_t length)
      |                          ~~~~~~~~~~~~^~~~~~~
Png.c:77:13: note: shadowed declaration is here
   77 | png_structp png_ptr;
      |             ^~~~~~~
Png.c: In function ‘PngFlushData’:
Png.c:610:38: warning: declaration of ‘png_ptr’ shadows a global declaration [-Wshadow]
  610 | static void PngFlushData(png_structp png_ptr)
      |                          ~~~~~~~~~~~~^~~~~~~
Png.c:77:13: note: shadowed declaration is here
   77 | png_structp png_ptr;
      |             ^~~~~~~