[LLVMbugs] [Bug 19824] Invalid code generation / optimization of C++ with -O3

[bugzilla-daemon at llvm.org]

http://llvm.org/bugs/show_bug.cgi?id=19824

Dane Springmeyer <dane at mapbox.com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
         Resolution|---                         |FIXED

--- Comment #3 from Dane Springmeyer <dane at mapbox.com> ---
Good news. This turns out to be a bug in our usage of c++11 lambdas and is not
a problem in clang/llvm. We were passing references to objects into the lambdas
that were not designed to be copied or moved, which was perhaps creating
undefined behavior. Our guess is that its the -argpromotion optimization that
was triggering this problem - without it we were getting away with dodgy code.
Our fix was to do some deep refactoring in our code to not rely on lambdas in
the same way:
https://github.com/mapnik/mapnik/commit/a49e1d075e75ac5ddc6101e7d85c15c8688b5a32.
Sorry for the noise and thanks for helping discuss this issue until it became
clearer.

-- 
You are receiving this mail because:
You are on the CC list for the bug.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.llvm.org/pipermail/llvm-bugs/attachments/20140605/a7c2ced9/attachment.html>