diff --git a/include/stdio.h b/include/stdio.h
index e23fbe5..fffa170 100644
--- a/include/stdio.h
+++ b/include/stdio.h
@@ -4,6 +4,7 @@
 #define LIBCRYPTOCOMPAT_STDIO_H
 
 #ifdef NO_ASPRINTF
+#include <stdarg.h>
 int vasprintf(char **str, const char *fmt, va_list ap);
 int asprintf(char **str, const char *fmt, ...);
 #endif