perf fails to compile on systems with GCC version11
as below:
In file included from /usr/include/string.h:519,
from
/home/athir/perf-tools-next/tools/include/linux/bitmap.h:5,
from /home/athir/perf-tools-next/tools/perf/util/pmu.h:5,
from /home/athir/perf-tools-next/tools/perf/util/evsel.h:14,
from /home/athir/perf-tools-next/tools/perf/util/evlist.h:14,
from tests/tool_pmu.c:3:
In function ‘strncpy’,
inlined from ‘do_test’ at tests/tool_pmu.c:25:3:
/usr/include/bits/string_fortified.h:95:10: error: ‘__builtin_strncpy’
specified bound 128 equals destination size [-Werror=stringop-truncation]
95 | return __builtin___strncpy_chk (__dest, __src, __len,
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
96 | __glibc_objsize (__dest));
| ~~~~~~~~~~~~~~~~~~~~~~~~~
The compile error is from strncpy refernce in do_test:
strncpy(str, tool_pmu__event_to_str(ev), sizeof(str));
This behaviour is not observed with GCC version 8, but observed
with GCC version 11 . This is message from gcc for detecting
truncation while using strncpu. Use snprintf instead of strncpy
here to be safe.
Signed-off-by: Athira Rajeev <atraj...@linux.vnet.ibm.com>
---
tools/perf/tests/tool_pmu.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/tools/perf/tests/tool_pmu.c b/tools/perf/tests/tool_pmu.c
index 94d0dd8fd3cb..297cc8c55579 100644
--- a/tools/perf/tests/tool_pmu.c
+++ b/tools/perf/tests/tool_pmu.c
@@ -22,7 +22,7 @@ static int do_test(enum tool_pmu_event ev, bool with_pmu)
if (with_pmu)
snprintf(str, sizeof(str), "tool/%s/",
tool_pmu__event_to_str(ev));
else
- strncpy(str, tool_pmu__event_to_str(ev), sizeof(str));
+ snprintf(str, sizeof(str), "%s", tool_pmu__event_to_str(ev));
parse_events_error__init(&err);
ret = parse_events(evlist, str, &err);
--
2.43.5
