Report error for PNG under Cairo

* src/image.c (lookup_rgb_color): Signal a file error instead
of dumping core when mishandling an image.

diff --git a/src/image.c b/src/image.c
index 4681cba1f879fd90ce300011a5e71bac9b8dc110..144fe30a7466497eb0905331cd982e8c13ebf978 100644 (file)
--- a/src/image.c
+++ b/src/image.c
@@ -4615,7 +4615,8 @@ lookup_rgb_color (struct frame *f, int r, int g, int b)
 #elif defined HAVE_NS
   return RGB_TO_ULONG (r >> 8, g >> 8, b >> 8);
 #else
-  eassume (false);
+  xsignal1 (Qfile_error,
+           build_string ("This Emacs mishandles this image file type"));
 #endif
 }