diff --git a/MagickCore/cache.c b/MagickCore/cache.c
index 312a323..b3d65ef 100644
--- a/MagickCore/cache.c
+++ b/MagickCore/cache.c
@@ -203,7 +203,7 @@
   cache_info->id=GetMagickThreadId();
   cache_info->number_threads=number_threads;
   if (number_threads == 0)
-    cache_info->number_threads=GetMagickResourceLimit(ThreadResource);
+    cache_info->number_threads=(size_t) GetMagickResourceLimit(ThreadResource);
   cache_info->nexus_info=AcquirePixelCacheNexus(cache_info->number_threads);
   if (cache_info->nexus_info == (NexusInfo **) NULL)
     ThrowFatalException(ResourceLimitFatalError,"MemoryAllocationFailed");