[Bug bootstrap/82670] New: UBSAN bootstrap broken after recent libsanitizer merge

[marxin at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82670

            Bug ID: 82670
           Summary: UBSAN bootstrap broken after recent libsanitizer merge
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: bootstrap
          Assignee: unassigned at gcc dot gnu.org
          Reporter: marxin at gcc dot gnu.org
                CC: jakub at gcc dot gnu.org
  Target Milestone: ---

Looks they recently added wrappers for signal-related functions:

/home/marxin/BIG/buildbot/slave/gcc-master-bootstrap-ubsan/build/builddir/./gcc/xgcc
-B/home/marxin/BIG/buildbot/slave/gcc-master-bootstrap-ubsan/build/builddir/./gcc/
-dumpspecs > tmp-specs
/bin/sh: line 1:  7075 Segmentation fault      (core dumped)
/home/marxin/BIG/buildbot/slave/gcc-master-bootstrap-ubsan/build/builddir/./gcc/xgcc
-B/home/marxin/BIG/buildbot/slave/gcc-master-bootstrap-ubsan/build/builddir/./gcc/
-dumpspecs > tmp-specs
make[3]: *** [Makefile:2037: specs] Error 139

It fails here:

   │0x60335b <__interceptor_signal(int, void*)+11>                             
    callq  0x605010 <__sanitizer::GetHandleSignalMode(int)>
   │0x603360 <__interceptor_signal(int, void*)+16>                             
    cmp    $0x2,%eax
   │0x603363 <__interceptor_signal(int, void*)+19>                             
    je     0x603376 <__interceptor_signal(int, void*)+38>
   │0x603365 <__interceptor_signal(int, void*)+21>                             
    add    $0x8,%rsp
   │0x603369 <__interceptor_signal(int, void*)+25>                             
    mov    %rbp,%rsi
   │0x60336c <__interceptor_signal(int, void*)+28>                             
    mov    %ebx,%edi
   │0x60336e <__interceptor_signal(int, void*)+30>                             
    pop    %rbx
   │0x60336f <__interceptor_signal(int, void*)+31>                             
    pop    %rbp
  >│0x603370 <__interceptor_signal(int, void*)+32>                             
    jmpq   *0x3e9f22(%rip)        # 0x9ed298
<_ZN14__interception11real_signalE>

It's strange because it should basically jump to
_ZN14__interception11real_signalE, but it's somehow zeroed:

Program received signal SIGSEGV, Segmentation fault.
0x0000000000000000 in ?? ()