Re: [PATCH 3/3] gimple-fold: Use ranges to simplify strncat and snprintf

[Siddhesh Poyarekar]

On 11/12/21 01:11, Siddhesh Poyarekar wrote:
Remove the warnings for strncat since it is already handled (and even
the error messages look identical) in gimple-ssa-warn-access.  Instead,
use len range to determine if it is within bounds of source and
destination and simplify it to strcat if it's safe.
Likewise for snprintf, use ranges to determine if it can be transformed
to strcpy.

gcc/ChangeLog:

        * gimple-fold.c (gimple_fold_builtin_strncat): Remove warnings
        and use ranges to determine if it is safe to transform to
        strcat.
        (gimple_fold_builtin_snprintf): Likewise.

gcc/testsuite/ChangeLog:

        * gcc.dg/fold-stringops-2.c: Define size_t.
        (safe1): Adjust.
        (safe4): New test.
        * gcc.dg/fold-stringops-3.c: New test.


Sorry, it looks like my last test run was stale and didn't catch the 
regressions dropping warnings caused.  I'll bring back the warnings in 
v2 with ranges.

Siddhesh