diff --git a/lib/libc/tests/stdio/getdelim_test.c b/lib/libc/tests/stdio/getdelim_test.c
index ffc6810dd616..b7596b36a2d4 100644
--- a/lib/libc/tests/stdio/getdelim_test.c
+++ b/lib/libc/tests/stdio/getdelim_test.c
@@ -177,6 +177,7 @@ ATF_TC_BODY(nul, tc)
 	char *line;
 	size_t linecap, n;
 
+	errno = 0;
 	line = NULL;
 	linecap = 0;
 	/* Make sure a NUL delimiter works. */