[lld] r248102 - COFF: Fix thread-safety bug.

[Rui Ueyama via llvm-commits]

I have no idea. CC'ing Peter since he may know about that.

On Sat, Sep 19, 2015 at 5:31 PM, David Blaikie <dblaikie at gmail.com> wrote:

>
>
> On Sat, Sep 19, 2015 at 4:14 PM, Rui Ueyama via llvm-commits <
> llvm-commits at lists.llvm.org> wrote:
>
>> Author: ruiu
>> Date: Sat Sep 19 18:14:51 2015
>> New Revision: 248102
>>
>> URL: http://llvm.org/viewvc/llvm-project?rev=248102&view=rev
>> Log:
>> COFF: Fix thread-safety bug.
>>
>> LTOModule doesn't seem to be thread-safe, so guard that with mutex.
>>
>
> Yeah, that seems unfortunate.
>
> Any idea where the thread unsafety comes from & whether we can/should fix
> it down the stack rather than in lld?
>
>
>>
>> Modified:
>>     lld/trunk/COFF/InputFiles.cpp
>>     lld/trunk/COFF/InputFiles.h
>>
>> Modified: lld/trunk/COFF/InputFiles.cpp
>> URL:
>> http://llvm.org/viewvc/llvm-project/lld/trunk/COFF/InputFiles.cpp?rev=248102&r1=248101&r2=248102&view=diff
>>
>> ==============================================================================
>> --- lld/trunk/COFF/InputFiles.cpp (original)
>> +++ lld/trunk/COFF/InputFiles.cpp Sat Sep 19 18:14:51 2015
>> @@ -310,6 +310,9 @@ void ImportFile::parse() {
>>  }
>>
>>  void BitcodeFile::parse() {
>> +  // Usually parse() is thread-safe, but bitcode file is an exception.
>> +  std::lock_guard<std::mutex> Lock(Mu);
>> +
>>    std::string Err;
>>    M.reset(LTOModule::createFromBuffer(MB.getBufferStart(),
>>                                        MB.getBufferSize(),
>> @@ -356,5 +359,7 @@ MachineTypes BitcodeFile::getMachineType
>>    }
>>  }
>>
>> +std::mutex BitcodeFile::Mu;
>> +
>>  } // namespace coff
>>  } // namespace lld
>>
>> Modified: lld/trunk/COFF/InputFiles.h
>> URL:
>> http://llvm.org/viewvc/llvm-project/lld/trunk/COFF/InputFiles.h?rev=248102&r1=248101&r2=248102&view=diff
>>
>> ==============================================================================
>> --- lld/trunk/COFF/InputFiles.h (original)
>> +++ lld/trunk/COFF/InputFiles.h Sat Sep 19 18:14:51 2015
>> @@ -17,6 +17,7 @@
>>  #include "llvm/Object/COFF.h"
>>  #include "llvm/Support/StringSaver.h"
>>  #include <memory>
>> +#include <mutex>
>>  #include <set>
>>  #include <vector>
>>
>> @@ -213,6 +214,7 @@ private:
>>    std::vector<SymbolBody *> SymbolBodies;
>>    llvm::BumpPtrAllocator Alloc;
>>    std::unique_ptr<LTOModule> M;
>> +  static std::mutex Mu;
>>  };
>>
>>  } // namespace coff
>>
>>
>> _______________________________________________
>> llvm-commits mailing list
>> llvm-commits at lists.llvm.org
>> http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-commits
>>
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.llvm.org/pipermail/llvm-commits/attachments/20150919/418f39b0/attachment.html>