https://gcc.gnu.org/bugzilla/show_bug.cgi?id=90378
Bug ID: 90378
Summary: [9 regression] -Os -flto miscompiles 454.calculix
after r266385 on Arm
Product: gcc
Version: 9.1.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: rtl-optimization
Assignee: unassigned at gcc dot gnu.org
Reporter: mkuvyrkov at gcc dot gnu.org
Target Milestone: ---
I'm investigating a miscompilation of 454.calculix, which occurs only with LTO
on ARMv7. Miscompilation results in SIGSEGV and seems to occur only on ARMv7
hardware (cortex-a15), same binary runs fine on ARMv8 hardware.
Miscompilation occurs at and after
===
commit 8fc3599dcab36e0b905fa442c0fc0a905280eea2 (HEAD)
Author: vmakarov <vmakarov@138bc75d-0d04-0410-961f-82ee72b054a4>
Date: Thu Nov 22 17:25:57 2018 +0000
2018-11-22 Vladimir Makarov <vmaka...@redhat.com>
PR rtl-optimization/87718
* ira-costs.c: Remove trailing white-spaces.
(record_operand_costs): Add a special treatment for moves
involving a hard register.
2018-11-22 Vladimir Makarov <vmaka...@redhat.com>
PR rtl-optimization/87718
* gcc.target/i386/pr82361-1.c: Check only the first operand of
moves.
git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@266385
138bc75d-0d04-0410-961f-82ee72b054a4
===
but I do not have hard evidence that this patch is the root cause. It may be
triggering a latent bug or even exposing undefined behavior in the benchmark.
I'm struggling to reduce the 300-object LTO compilation down to something
manageable. Advice and ideas on where to look are appreciated.
