[LLVMdev] 3.4 branch gcc 4.9 build error

[Tom Stellard]

On Thu, May 15, 2014 at 01:38:32PM +0200, Tuncer Ayaz wrote:
> On Thu, 15 May 2014 02:25:30 +0200, Tom Stellard wrote:
> 
> > On Sat, May 10, 2014 at 11:48:23PM +0200, Tuncer Ayaz wrote:
> > > Tom,
> > >
> > > now that 3.4.1 is out, any chance of a 3.4.2 with just the three
> > > fixes or at least merging them to the 3.4 branch?
> >
> > I've pushed the two approved patches to the 3.4 branch, can you
> > verify that they work with gcc 4.9.
> 
> Thanks, Tom.
> 
> Fresh (svn rev 208853) checkout of llvm, clang, etc:
> 
> llvm[1]: Compiling APFloat.cpp for Release build
> In file included from APFloat.cpp:15:
> In file included from /tmp/llvm/include/llvm/ADT/APFloat.h:20:
> In file included from /tmp/llvm/include/llvm/ADT/APInt.h:19:
> In file included from /tmp/llvm/include/llvm/ADT/ArrayRef.h:14:
> In file included from /tmp/llvm/include/llvm/ADT/SmallVector.h:17:
> In file included from /tmp/llvm/include/llvm/Support/AlignOf.h:19:
> /usr/lib64/[...]/c++/4.9.0/cstddef:51:11: error:
>       no member named 'max_align_t' in the global namespace
>   using ::max_align_t;
>         ~~^
> 1 error generated.
> 

Is this trunk or the 3.4 branch?

> As the fixes got merged to the release_34 branch, I went to check the
> local configure options and noticed I was passing --enable-cxx11. If I
> omit that, there's no max_align_t error. I don't remember when I added
> that, but it used to build prior to gcc 4.9. Just so I understand, is
> that flag meant to be enabled (and known to work) when llvm is built
> by clang, or is that also in need of fixing for gcc 4.9?

So clang/llvm will only fail to build with gcc 4.9 if the --enable-cxx11 flag is used?

-Tom