[Bug lto/85893] New: [regression] Variables promoted to Gimple registers by aliasing are not getting debug statements (if -flto used).

[jason.vas.dias at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85893

            Bug ID: 85893
           Summary: [regression] Variables promoted to Gimple registers by
                    aliasing are not getting debug statements (if -flto
                    used).
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: lto
          Assignee: unassigned at gcc dot gnu.org
          Reporter: jason.vas.dias at gmail dot com
                CC: marxin at gcc dot gnu.org
  Target Milestone: ---

After building gcc-5-branch, gcc-6-branch, and gcc-7-branch,
on an x86_64 Linux glibc-2.17 + binutils 2.30 (also on a 
glibc-2.27 + binutils 2.30 system), they all fail the
gcc.dg/guality/pr41616-1.C testsuite test with any
'-flto' enabling arguments:

Without -flto enabled, the tests pass:

../xgcc -B../gcc/ ../gcc.dg/guality/pr41616-1.c ...\
   -flto -fno-use-linker-plugin -flto-partition=none \
   -O2 -g -fgnu89-inline -lm -o ./pr41616-1.exe
spawn [open ...]
PASS: b is -1
PASS: b is 1
PASS: 2 PASS, 0 FAIL, 0 UNRESOLVED
PASS: gcc.dg/guality/pr41616-1.c   -O2 -flto -fno-use-linker-plugin
-flto-partition=none  execution test
...

With -flto enabled, they fail:
../xgcc -B../gcc/ ../gcc.dg/guality/pr41616-1.c ...\
   -flto -fuse-linker-plugin -fno-fat-lto-objects \
   -O2 -g -fgnu89-inline -lm -o ./pr41616-1.exe

spawn [open ...]
PASS: b is -1
FAIL: b is -1, not 1
FAIL: 1 PASS, 1 FAIL, 0 UNRESOLVED
FAIL: gcc.dg/guality/pr41616-1.c   -O2 -flto -fuse-linker-plugin
-fno-fat-lto-objects  execution test


This happens with builds of gcc-5.5.0, gcc-6.4.1, and gcc-7.3.1 .

All other -flto testsuite tests of these builds are passing.