From b575249eb334e3f95319eea68c9606f43db05a07 Mon Sep 17 00:00:00 2001 From: Eric Biggers Date: Sat, 21 Jan 2023 12:32:02 -0800 Subject: [PATCH] lib/blkid: suppress -Wunused-result warning in blkid_flush_cache() When _FORTIFY_SOURCE is defined, glibc annotates link() with the warn_unused_result function attribute. With gcc, that makes '(void) link()' cause a -Wunused-result warning, despite the explicit cast to void. That's annoying, since the use case in lib/blkid/save.c is legitimate (opportunistic backup). So let's suppress this warning. Signed-off-by: Eric Biggers Signed-off-by: Theodore Ts'o --- lib/blkid/save.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/lib/blkid/save.c b/lib/blkid/save.c index 036f07a..6f4499c 100644 --- a/lib/blkid/save.c +++ b/lib/blkid/save.c @@ -154,7 +154,15 @@ int blkid_flush_cache(blkid_cache cache) if (backup) { sprintf(backup, "%s.old", filename); unlink(backup); +#if defined(__GNUC__) && __GNUC__ >= 5 +/* explicit (void) cast is not enough with glibc and _FORTIFY_SOURCE */ +#pragma GCC diagnostic push +#pragma GCC diagnostic ignored "-Wunused-result" +#endif (void) link(filename, backup); +#if defined(__GNUC__) && __GNUC__ >= 5 +#pragma GCC diagnostic pop +#endif free(backup); } if (rename(opened, filename) < 0) -- 1.8.3.1