http://bugs.gentoo.org/show_bug.cgi?id=383799#c13
Upstream: http://www.avasys.jp/cgi-bin/lx/bbs/en/scanner-bbs/hyperbbs.cgi?mode=view;Code=5197

--- lib/pngstream.cc
+++ lib/pngstream.cc
@@ -76,7 +76,12 @@
         set_error_handler (_png, _info);
 
         lib->write_flush (_png);
+/* when not interlacing (ie, only one pass), number of rows is image height:  _v_sz */
+#if PNG_LIBPNG_VER > 10499
+        if (!_footer && _v_sz == lib->get_current_row_number(_png))
+#else
         if (!_footer && _png->num_rows == _png->flush_rows)
+#endif
           {
             lib->write_end (_png, _info);
             _footer = true;
@@ -161,6 +166,9 @@
     funcsym (write_row);
     funcsym (write_flush);
     funcsym (write_end);
+#if PNG_LIBPNG_VER > 10499
+    funcsym (get_current_row_number);
+#endif
 
     if (lib->access_version_number
         && lib->create_write_struct
@@ -170,6 +178,9 @@
         && lib->set_IHDR
         && lib->set_pHYs
         && lib->set_invert_mono
+#if PNG_LIBPNG_VER > 10499
+	&& lib->get_current_row_number
+#endif
         && lib->write_info
         && lib->write_row
         && lib->write_flush
--- lib/pngstream.hh
+++ lib/pngstream.hh
@@ -108,6 +108,10 @@
                png_structp);
       fundecl (void, write_end,
                png_structp, png_infop);
+#if PNG_LIBPNG_VER > 10499
+      fundecl (png_uint_32, get_current_row_number,
+               png_structp);
+#endif
 #endif /* HAVE_PNG_H */
     };
     static png_lib_handle *lib;