diff mbox series

[10/38] lib/blkid: suppress -Wunused-result warning in blkid_flush_cache()

Message ID 20230121203230.27624-11-ebiggers@kernel.org
State Accepted
Headers show
Series e2fsprogs: misc fixes, and add a GitHub Actions file | expand

Commit Message

Eric Biggers Jan. 21, 2023, 8:32 p.m. UTC 
From: Eric Biggers <ebiggers@google.com>

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 <ebiggers@google.com>
---
 lib/blkid/save.c | 8 ++++++++
 1 file changed, 8 insertions(+)
diff mbox series

Patch

diff --git a/lib/blkid/save.c b/lib/blkid/save.c
index 036f07a4a..6f4499cfd 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)