On 7/22/2021 6:34 AM, Richard Biener wrote:
We can improve uninit warnings from the early pass by looking
at PHI arguments on fallthru edges that are uninitialized and
have uses that are before a possible loop exit. This catches
some cases earlier that we'd only warn in a more confusing
way after early inlining as seen by testcase adjustments.
It introduces
FAIL: gcc.dg/uninit-23.c (test for excess errors)
where we additionally warn
gcc.dg/uninit-23.c:21:13: warning: 't4' is used uninitialized [-Wuninitialized]
which I think is OK even if it's not obvious that the new
warning is an improvement when you look at the obvious source.
Somehow for all cases I never get the `'foo' was declared here`
notes, I didn't dig why that happens but it's odd.
Bootstrapped and tested on x86_64-unknown-linux-gnu.
Any comments?
Thanks,
Richard.
2021-07-22 Richard Biener <rguent...@suse.de>
PR tree-optimization/101573
* tree-ssa-uninit.c (warn_uninitialized_vars): Look at
uninitialized PHI arg defs in some constrained cases.
(execute_early_warn_uninitialized): Calculate dominators.
* gcc.dg/uninit-pr101573.c: New testcase.
* gcc.dg/uninit-15-O0.c: Adjust.
* gcc.dg/uninit-15.c: Likewise.
* gcc.dg/uninit-23.c: Likewise.
* c-c++-common/uninit-17.c: Likewise.
OK. Like Martin I think the new code in a function would be easier to
read. So if you could factor the bits into a new function it'd be
appreciated.
I wouldn't be terribly surprised if we find additional fallout on other
targets, but we can fault in those fixes.
Jeff
