[LLVMdev] 3.4 branch gcc 4.9 build error

[Tuncer Ayaz]

On 5/15/14, Tom Stellard wrote:
> 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?

release_34

> > 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?

Yes.