[Bug lto/65316] New: [5 Regression] LTO: Uninitialized memory / ICE with -g -fno-lto-odr-type-merging: in types_same_for_odr, at ipa-devirt.c:465

[burnus at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65316

            Bug ID: 65316
           Summary: [5 Regression] LTO: Uninitialized memory / ICE with -g
                    -fno-lto-odr-type-merging: in types_same_for_odr, at
                    ipa-devirt.c:465
           Product: gcc
           Version: 5.0
            Status: UNCONFIRMED
          Keywords: ice-on-valid-code
          Severity: normal
          Priority: P3
         Component: lto
          Assignee: unassigned at gcc dot gnu.org
          Reporter: burnus at gcc dot gnu.org
                CC: hubicka at gcc dot gnu.org

Created attachment 34954
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=34954&action=edit
one.ii

Follow up to PR65276 and PR65302.

It turned out that is issue is due to uninitialized memory. Thus, if the last
command succeeds, simply try again a couple of times (in delta, I called it up
to 25 times) - or run it under valgrind or similar.

It fails with the ICE:

lto1: internal compiler error: in types_same_for_odr, at ipa-devirt.c:465


touch two.ii
g++ -c -std=c++11 -g2 -fno-lto-odr-type-merging -flto -O2 two.ii one.ii
gcc -r -nostdlib -O2 -fno-lto-odr-type-merging -flto one.o two.o