Messages in this thread | | | Date | Thu, 12 Oct 2023 00:11:13 +0200 | From | Ingo Molnar <> | Subject | Re: [PATCH] locking/lockdep: fix format-truncation compiler-warning |
| |
* Lucy Mielke <lucymielke@icloud.com> wrote:
> Compiler: gcc x86_64 v13.2.1 > Config: allyesconfig, "treat warnings as errors" unset > > This fixes a warning emitted by gcc, stating the output may be > truncated. The fix included increasing the buffer size to the one > denoted by gcc.
Mind including the output by GCC in the changelog?
> static void seq_time(struct seq_file *m, s64 time) > { > - char num[15]; > + char num[22]; > > snprint_time(num, sizeof(num), time); > seq_printf(m, " %14s", num);
Fun.
So this:
static void snprint_time(char *buf, size_t bufsiz, s64 nr) { s64 div; s32 rem;
nr += 5; /* for display rounding */ div = div_s64_rem(nr, 1000, &rem); snprintf(buf, bufsiz, "%lld.%02d", (long long)div, (int)rem/10); }
... actually needs 21+1 bytes?
Which I suppose is true - longest s64 is "-9223372036854775808"-ish, which converted to the fixed-point float format above is "-9223372036854775.80": 21 bytes, plus termination is another byte: 22.
Maybe put this into the changelog too, instead of relying on magic GCC calculations only. :-)
Thanks,
Ingo
| |