PNG_EXPORT_VAR 603 third_party/libpng/png.h PNG_EXPORT_VAR (PNG_CONST char) png_libpng_ver[18]; PNG_EXPORT_VAR 1517 third_party/libpng/pngconf.h # define PNG_EXPORT_VAR(type) PNG_DATA_EXPORT PNG_EXPORT_VAR 1528 third_party/libpng/pngconf.h # define PNG_EXPORT_VAR(type) extern PNG_IMPEXP type