Corrected cast.

diff --git a/coders/png.c b/coders/png.c
index ec61508b38c373cd1ab70925fdfade132d73d880..31b934d11b66de5eeb948b0db98d3d9b31836494 100644 (file)
--- a/coders/png.c
+++ b/coders/png.c
@@ -2450,8 +2450,8 @@ static Image *ReadOnePNGImage(MngInfo *mng_info,
 #if (PNG_LIBPNG_VER >= 10401)
     option=GetImageOption(image_info,"png:chunk-malloc-max");
     if (option != (const char *) NULL)
-      png_set_chunk_malloc_max(ping,(png_alloc_size_t) MagickMin((ssize_t)
-        PNG_SIZE_MAX,StringToLong(option)));
+      png_set_chunk_malloc_max(ping,(png_alloc_size_t) MagickMin(PNG_SIZE_MAX,
+        (size_t) StringToLong(option)));
     else
       png_set_chunk_malloc_max(ping,(png_alloc_size_t) GetMaxMemoryRequest());
 #endif