diff --git a/reactos/sdk/lib/crt/string/strtoi64.c b/reactos/sdk/lib/crt/string/strtoi64.c
index 37976632968..3d5cadebfc0 100644
--- a/reactos/sdk/lib/crt/string/strtoi64.c
+++ b/reactos/sdk/lib/crt/string/strtoi64.c
@@ -18,6 +18,9 @@ __int64 CDECL _strtoi64_l(const char *nptr, char **endptr, int base, _locale_t l
     TRACE("(%s %p %d %p)\n", debugstr_a(nptr), endptr, base, locale);
 #endif
 
+#ifndef __REACTOS__
+    if (!MSVCRT_CHECK_PMT(nptr != NULL)) return 0;
+#endif
     if (!MSVCRT_CHECK_PMT(base == 0 || base >= 2)) return 0;
     if (!MSVCRT_CHECK_PMT(base <= 36)) return 0;