1 files changed, 3 insertions, 1 deletions
diff --git a/generic/tclInt.h b/generic/tclInt.h
index 42c13dd..fa91528 100644
--- a/generic/tclInt.h
+++ b/generic/tclInt.h
@@ -48,7 +48,9 @@
 #else
 #include <string.h>
 #endif
-#ifdef STDC_HEADERS
+#if defined(_WIN32)
+#include <crtdefs.h>
+#elif defined(STDC_HEADERS)
 #include <stddef.h>
 #else
 typedef int ptrdiff_t;