On 2024-07-26 13:11, Jakub Jelinek wrote:
On Thu, Jul 25, 2024 at 07:48:38PM -0400, Siddhesh Poyarekar wrote:
The code to scale ranges for wide chars in format_string incorrectly
checks range.likely to scale range.unlikely, which is a copy-paste typo
from the immediate previous condition.
gcc/ChangeLog:
gimple-ssa-sprintf.cc (format_string): Fix type in range check
for UNLIKELY for wide chars.
Signed-off-by: Siddhesh Poyarekar <siddh...@gotplt.org>
LGTM.
Thanks, pushed.
What exactly the code really wants to do is unclear to me, what does
the INT_MAX on the target have to do with the minimum/maximum/expected
sizes of %S or %ls printed strings is unclear, target PTRDIFF_MAX
I think that is because the printf family returns the number of
bytes/chars written in an int, which imposes the INT_MAX limitation on
the format string expansion.
maybe. And why it uses this
if (slen.range.something < target_int_max ())
slen.range.something *= something_else;
rather than say
slen.range.something
= MIN (slang.range.something * something_else, target_int_max ());
perhaps with some overflow checking is also something that is hard to guess.
That's what I tried first but I settled for the minimal change because I
didn't want to dig in deeper than I had time for to at the moment.
Further down it checks if MAX and UNLIKELY cross INT_MAX and then resets
to INT_MAX, but that looks suspicious on, e.g. 32-bit targets. The code
could use some refactoring/cleanup.
Thanks,
Sid
