[compiler-rt] r281970 - tsan: check more addresses in CheckShadowMapping

[Dmitry Vyukov via llvm-commits]

On Tue, Sep 20, 2016 at 4:29 PM, Renato Golin <renato.golin at linaro.org> wrote:
> On 20 September 2016 at 14:30, Dmitry Vyukov via llvm-commits
> <llvm-commits at lists.llvm.org> wrote:
>> Author: dvyukov
>> Date: Tue Sep 20 08:30:01 2016
>> New Revision: 281970
>>
>> URL: http://llvm.org/viewvc/llvm-project?rev=281970&view=rev
>> Log:
>> tsan: check more addresses in CheckShadowMapping
>
> Hi Dmitry,
>
> This is an odd failure:
>
> http://lab.llvm.org:8011/builders/clang-cmake-aarch64-42vma/builds/12021
>
> The 39-bit bots haven't caught with it yet, would be good to know if
> this is a 42-vma only issue...


Looks like there is a bug in the shadow mapping -- it is not a
bijection. At the very least it leads to bogus addresses in race
reports.
We can revert the commit for now, but I am working on a more complex
mapping for x86_64 and this extended check would be useful (as proven
by this failure).