From: Yiyang Chen Date: Thu, 23 Apr 2026 15:11:39 +0000 (+0800) Subject: tools/accounting/getdelays: fix -Wformat-truncation warning in format_timespec X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=0e75190fe40093d85c0c698d9f8dca66df842605;p=thirdparty%2Flinux.git tools/accounting/getdelays: fix -Wformat-truncation warning in format_timespec Reproduce with GCC 13.3.0: $ cd tools/accounting $ make This emits: getdelays.c: In function `format_timespec': getdelays.c:218:67: warning: `:' directive output may be truncated writing 1 byte into a region of size between 0 and 16 [-Wformat-truncation=] 218 | snprintf(buffer, sizeof(buffer), "%04d-%02d-%02dT%02d:%02d:%02d", | getdelays.c:218:9: note: `snprintf' output between 20 and 72 bytes into a destination of size 32 The problem is that %04d and %02d specify minimum field widths only. GCC cannot prove that formatting tm_year + 1900 and the other struct tm fields will always fit in the fixed 32-byte buffer, so it warns about possible truncation. Fix this by replacing the manual snprintf() formatting with strftime("%Y-%m-%dT%H:%M:%S", ...). That matches the data we already have in struct tm, keeps the intended timestamp format, and avoids the warning when building tools/accounting with GCC. Link: https://lore.kernel.org/87d9723e0b59d816ee2e4bd7cddd58a54c6c9f91.1776956545.git.cyyzero16@gmail.com Signed-off-by: Yiyang Chen Cc: Fan Yu Cc: Wang Yaxin Signed-off-by: Andrew Morton --- diff --git a/tools/accounting/getdelays.c b/tools/accounting/getdelays.c index 368a622ca0273..caa5fe9dd5734 100644 --- a/tools/accounting/getdelays.c +++ b/tools/accounting/getdelays.c @@ -241,13 +241,7 @@ static const char *format_timespec(struct __kernel_timespec *ts) if (localtime_r(&time_sec, &tm_info) == NULL) return "N/A"; - snprintf(buffer, sizeof(buffer), "%04d-%02d-%02dT%02d:%02d:%02d", - tm_info.tm_year + 1900, - tm_info.tm_mon + 1, - tm_info.tm_mday, - tm_info.tm_hour, - tm_info.tm_min, - tm_info.tm_sec); + strftime(buffer, sizeof(buffer), "%Y-%m-%dT%H:%M:%S", &tm_info); return buffer; }