diff --git a/src/pthreads.c b/src/pthreads.c
index ea09e53..dad9d9b 100644
--- a/src/pthreads.c
+++ b/src/pthreads.c
@@ -74,7 +74,7 @@
 #endif
 
 /* Alloca */
-#if defined(_MSC_VER)
+#if defined(_WIN32)
 #include <malloc.h>
 #define alloca _alloca
 #elif !defined(alloca) && defined(__GNUC__)