[Bug sanitizer/67258] "invalid vptr" false positive from ubsan for virtual inheritance

[trippels at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67258

--- Comment #4 from Markus Trippelsdorf <trippels at gcc dot gnu.org> ---
Author: trippels
Date: Wed Sep  9 16:39:32 2015
New Revision: 227592

URL: https://gcc.gnu.org/viewcvs?rev=227592&root=gcc&view=rev
Log:
Fix sanitizer/67258 by cherry picking upstream patch

        PR sanitizer/67258
        * ubsan/ubsan_type_hash.cc: Cherry pick upstream r244101.

Upstream patch:
commit 1d2477faafda9ad2cc19927b3c31efd22747f013
Author: Alexey Samsonov <vonosmas@gmail.com>
Date:   Wed Aug 5 19:35:46 2015 +0000

    [UBSan] Fix UBSan-vptr false positive.

    Offset from vptr to the start of most-derived object can actually
    be positive in some virtual base class vtables.

    Patch by Stephan Bergmann!

    git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@244101
91177308-0d34-0410-b5e6-96231b3b80d8

Added:
    branches/gcc-5-branch/gcc/testsuite/g++.dg/ubsan/vptr-10.C
Modified:
    branches/gcc-5-branch/libsanitizer/ChangeLog
    branches/gcc-5-branch/libsanitizer/ubsan/ubsan_type_hash.cc