From: Martin Sebor <msebor@redhat.com>
Date: Mon, 11 Oct 2021 15:36:57 +0000 (-0600)
Subject: resolv: Avoid GCC 12 false positive warning [BZ #28439].
X-Git-Tag: glibc-2.35~431
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=eb73b87897798de981dbbf019aa957045d768adb;p=thirdparty%2Fglibc.git

resolv: Avoid GCC 12 false positive warning [BZ #28439].

Replace a call to sprintf with an equivalent pair of stpcpy/strcpy calls
to avoid a GCC 12 -Wformat-overflow false positive due to recent optimizer
improvements.
---

diff --git a/resolv/res_query.c b/resolv/res_query.c
index 75b0e5f2f7b..5d0a68dc81f 100644
--- a/resolv/res_query.c
+++ b/resolv/res_query.c
@@ -610,7 +610,9 @@ __res_context_querydomain (struct resolv_context *ctx,
 			RES_SET_H_ERRNO(statp, NO_RECOVERY);
 			return (-1);
 		}
-		sprintf(nbuf, "%s.%s", name, domain);
+		char *p = __stpcpy (nbuf, name);
+		*p++ = '.';
+		strcpy (p, domain);
 	}
 	return __res_context_query (ctx, longname, class, type, answer,
 				    anslen, answerp, answerp2, nanswerp2,