+#define qpng_jmpbuf_14(png_ptr) (*qpng_set_longjmp_fn((png_ptr), longjmp, sizeof (jmp_buf)))
+
+// libpng 1.2 longjmp hack
+#define qpng_jmpbuf_12(png_ptr) (*((jmp_buf *) png_ptr))
+
+// all version support
+#define qpng_jmpbuf(png_ptr) \
+ (qpng_set_longjmp_fn ? qpng_jmpbuf_14(png_ptr) : qpng_jmpbuf_12(png_ptr))