diff -urp a/src/OpenPNG.cpp b/src/OpenPNG.cpp
--- a/src/OpenPNG.cpp
+++ b/src/OpenPNG.cpp
@@ -5,6 +5,7 @@
  */
 
 
+#include <string.h>
 #include <png.h>
 #include "Debug.h"
 #include "Open.h"
@@ -38,9 +39,7 @@ namespace corona {
 
   void PNG_error_function(png_structp png_ptr, png_const_charp warning) {
     // copied from libpng's pngerror.cpp, but without the fprintf
-    jmp_buf jmpbuf;
-    memcpy(jmpbuf, png_ptr->jmpbuf, sizeof(jmp_buf));
-    longjmp(jmpbuf, 1);
+    longjmp(png_jmpbuf(png_ptr), 1);
   }
 
   //////////////////////////////////////////////////////////////////////////////
diff -urp a/src/SavePNG.cpp b/src/SavePNG.cpp
--- a/src/SavePNG.cpp
+++ b/src/SavePNG.cpp
@@ -1,4 +1,5 @@
 #include <memory>
+#include <string.h>
 #include <png.h>
 #include "Debug.h"
 #include "Save.h"
@@ -145,7 +146,6 @@ namespace corona {
       pixels += width * color_format_bpp;      
     }
     png_set_rows(png_ptr, info_ptr, (png_bytepp)rows);
-    info_ptr->valid |= PNG_INFO_IDAT;
 
     // actually write the image
     png_write_png(png_ptr, info_ptr, PNG_TRANSFORM_IDENTITY, NULL);