[llvm-dev] (Thin)LTO llvm build

[Carsten Mattner via llvm-dev]

On Fri, Sep 16, 2016 at 10:18 PM, Teresa Johnson <tejohnson at google.com> wrote:
>
> Cc'ing llvm-dev again in case someone knows what is going on.
>
> That error is coming from a polly configure script, which I don't
> have cloned into my own tree. Not sure why polly would behave
> differently when configuring for ThinLTO. Does polly configure ok
> when configuring the same way, but for regular LTO?

Yes it does, and I don't remember when I've added it, meaning it's
been working when bootstrapping llvm with the host gcc toolchain, for
a long time.

> On Fri, Sep 16, 2016 at 12:36 PM, Carsten Mattner <carstenmattner at gmail.com> wrote:
> >
> > Hi Teresa,
> >
> > I've just attempted a THIN_LTO build again, and the
> > error I ran into is as follows, and happens during
> > cmake. I'm explicitly telling cmake to us llvm-ar and llvm-ranlib
> > as suggested.
> >
> > [...]
> > -- Performing Test COMPILER_RT_HAS_STATIC_FLAG - Success
> > -- Performing Test COMPILER_RT_SUPPORTS_ATOMIC_KEYWORD
> > -- Performing Test COMPILER_RT_SUPPORTS_ATOMIC_KEYWORD - Success
> > -- Builtin supported architectures:
> > -- ISL version: isl-0.17.1-164-gcbba1b6
> > -- Performing Test HAS_ATTRIBUTE_WARN_UNUSED_RESULT
> > -- Performing Test HAS_ATTRIBUTE_WARN_UNUSED_RESULT - Failed
> > -- Performing Test HAVE___ATTRIBUTE__
> > -- Performing Test HAVE___ATTRIBUTE__ - Failed
> > -- Performing Test HAVE_DECL_FFS
> > -- Performing Test HAVE_DECL_FFS - Failed
> > -- Performing Test HAVE_DECL___BUILTIN_FFS
> > -- Performing Test HAVE_DECL___BUILTIN_FFS - Failed
> > -- Performing Test HAVE_DECL__BITSCANFORWARD
> > -- Performing Test HAVE_DECL__BITSCANFORWARD - Failed
> > CMake Error at tools/polly/lib/External/CMakeLists.txt:90 (message):
> >   No ffs implementation found
> > [...]