[PATCH 6.6 153/175] libbpf: Fix -Wdiscarded-qualifiers under C23

Greg Kroah-Hartman
2026-03-31T16:31:30Z

From: Mikhail Gavrilov <mikhail.v.gavrilov@gmail.com>

commit d70f79fef65810faf64dbae1f3a1b5623cdb2345 upstream.

glibc ≥ 2.42 (GCC 15) defaults to -std=gnu23, which promotes
-Wdiscarded-qualifiers to an error.

In C23, strstr() and strchr() return "const char *".

Change variable types to const char * where the pointers are never
modified (res, sym_sfx, next_path).

[ shung-hsi.yu: needed to fix kernel build failure due to libbpf since glibc
2.43+ (which adds 'const' qualifier to strstr) ]
[ Jonas Rebmann: down to one declaration on 6.6 to resolve build error
with glibc 2.43 ]

Suggested-by: Florian Weimer <fweimer@redhat.com>
Suggested-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Mikhail Gavrilov <mikhail.v.gavrilov@gmail.com>
Link: https://lore.kernel.org/r/20251206092825.1471385-1-mikhail.v.gavrilov@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Shung-Hsi Yu <shung-hsi.yu@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Jonas Rebmann <kernel@schlaraffenlan.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
tools/lib/bpf/libbpf.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -11247,7 +11247,7 @@ static int resolve_full_path(const char
if (!search_paths[i])
continue;
for (s = search_paths[i]; s != NULL; s = strchr(s, ':')) {
- char *next_path;
+ const char *next_path;
int seg_len;

if (s[0] == ':')