diff --git a/source/mjpeg_decoder.cc b/source/mjpeg_decoder.cc
index 0141da8a1..66b18b7be 100644
--- a/source/mjpeg_decoder.cc
+++ b/source/mjpeg_decoder.cc
@@ -13,8 +13,12 @@
 #ifdef HAVE_JPEG
 #include <assert.h>
 
+#if !defined(TARGET_IPHONE_SIMULATOR)
+#define TARGET_IPHONE_SIMULATOR 0
+#endif
+
 #if !defined(__pnacl__) && !defined(__CLR_VER) && \
-    !defined(COVERAGE_ENABLED) && !defined(TARGET_IPHONE_SIMULATOR)
+    !defined(COVERAGE_ENABLED) && !TARGET_IPHONE_SIMULATOR
 // Must be included before jpeglib.
 #include <setjmp.h>
 #define HAVE_SETJMP