[PATCH stable 6.6] libbpf: Fix -Wdiscarded-qualifiers under C23

[Jonas Rebmann <kernel@schlaraffenlan.de>]

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>
---
 tools/lib/bpf/libbpf.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index 95f2ffefff3f..802ae6dbddfa 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -11247,7 +11247,7 @@ static int resolve_full_path(const char *file, char *result, size_t result_sz)
 		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] == ':')

---
base-commit: 4fc00fe35d46b4fc8dac2eb543a0e3d44bb15f47
change-id: 20260323-linux-6-6-y-c23-23ffd3281c71

Best regards,
--  
Jonas Rebmann <kernel@schlaraffenlan.de>