diff --git a/libc/stdio/fread.c b/libc/stdio/fread.c
index 7b858ae..b6a3077 100644
--- a/libc/stdio/fread.c
+++ b/libc/stdio/fread.c
@@ -43,6 +43,8 @@
 size_t
 fread(void *buf, size_t size, size_t count, FILE *fp) __overloadable
 {
+	CHECK_FP(fp);
+
 	/*
 	 * Extension:  Catch integer overflow.
 	 */