[Bug lto/66815] New: Segfault with -lto and libitm

["heiner.litz at gmail dot com" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66815

            Bug ID: 66815
           Summary: Segfault with -lto and libitm
           Product: gcc
           Version: 5.1.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: lto
          Assignee: unassigned at gcc dot gnu.org
          Reporter: heiner.litz at gmail dot com
  Target Milestone: ---

When I compile STAMP's intruder with libitm and link time optimization (-flto),
execution fails (if compiled without lto it runs fine):

Program received signal SIGABRT, Aborted.

0x00007ffff6e12cc9 in __GI_raise (sig=sig@entry=6) at
../nptl/sysdeps/unix/sysv/linux/raise.c:56
56      ../nptl/sysdeps/unix/sysv/linux/raise.c: No such file or directory.
(gdb) bt
#0  0x00007ffff6e12cc9 in __GI_raise (sig=sig@entry=6) at
../nptl/sysdeps/unix/sysv/linux/raise.c:56
#1  0x00007ffff6e160d8 in __GI_abort () at abort.c:89
#2  0x00007ffff71a9db8 in _ITM_getTMCloneSafe () from
/usr/lib/x86_64-linux-gnu/libitm.so.1
#3  0x0000000000403f16 in processPackets.lto_priv.5 ()
#4  0x0000000000404a5d in threadWait.lto_priv.11 ()
#5  0x000000000040193a in main ()


The problem seems to be that no calls to _ITM_registerTMCloneTable (void *xent,
size_t size) in libitm/clone.cc are ever emitted and hence access to the clone
table fails. This error occurs with gcc4.9 and gcc5.1

to reproduce:
1. get STAMP: https://github.com/mfs409/stamp.git
2. enable lto by modifying <PATH-TO-STAMP>/stamp/TRANSACT/Makefile.common
3. export ITM_DEFAULT_METHOD=ml_wt
4. run <PATH_TO_STAMP>/stamp/obj/intruder/intruder