On 05/20/2019 11:49 PM, Matteo Croce wrote: > GCC 9 fails to calculate the size of local constant strings and produces a > false positive: > > samples/bpf/task_fd_query_user.c: In function ‘test_debug_fs_uprobe’: > samples/bpf/task_fd_query_user.c:242:67: warning: ‘%s’ directive output may be truncated writing up to 255 bytes into a region of size 215 [-Wformat-truncation=] > 242 | snprintf(buf, sizeof(buf), "/sys/kernel/debug/tracing/events/%ss/%s/id", > | ^~ > 243 | event_type, event_alias); > | ~~~~~~~~~~~ > samples/bpf/task_fd_query_user.c:242:2: note: ‘snprintf’ output between 45 and 300 bytes into a destination of size 256 > 242 | snprintf(buf, sizeof(buf), "/sys/kernel/debug/tracing/events/%ss/%s/id", > | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > 243 | event_type, event_alias); > | ~~~~~~~~~~~~~~~~~~~~~~~~ > > Workaround this by lowering the buffer size to a reasonable value. > Related GCC Bugzilla: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83431 > > Signed-off-by: Matteo Croce <mcroce@xxxxxxxxxx> Applied, thanks!
