[CMake] Status of clang support?

[Alexander Neundorf]

On Wednesday 27 October 2010, Campbell Barton wrote:
> On Tue, Oct 26, 2010 at 1:02 AM, Mateusz Loskot <mateusz at loskot.net> wrote:
> > On 25/10/10 01:38, Mateusz Loskot wrote:
> >> On 24/10/10 23:00, Ryan Pavlik wrote:
> >>> My best guess would be to check for some Clang-specific defines,
> >>> similar to the platform checks.  Actually, it looks like in the Git
> >>> repository of CMake, there is now some Clang-specific support:
> >>> http://github.com/Kitware/CMake/commit/571dc7489111893355deba710feee599
> >>>0bce92e4 I think that this commit is included in 2.8.2.
> >>
> >> Ryan,
> >>
> >> It's very good to know.
> >>
> >>> I've made a note on that commit as to where I think a Clang-specific
> >>> variable might be set.
> >>
> >> I've seen, great!
> >>
> >>> For now, you might be able to look at the
> >>> value of CMAKE_CXX_COMPILER_ID for a more general solution - it seems
> >>> like that might contain "Clang" if building using Clang.
> >>
> >> I'm having access to CMake 2.8.0 at this moment
> >> And, this version sets CMAKE_CXX_COMPILER_ID to GNU, even if
> >> C/C++ compilers set to clang:
> >>
> >> cmake -DCMAKE_C_COMPILER=clang -DCMAKE_CXX_COMPILER=clang++
> >>
> >> Also, simple test always reports the "gnu".
> >>
> >> if("${CMAKE_CXX_COMPILER_ID}" MATCHES "clang")
> >>   message(STATUS "clang")
> >> elseif("${CMAKE_CXX_COMPILER_ID}" MATCHES "GNU")
> >>   message(STATUS "gnu")
> >> endif()
> >>
> >> I will try 2.8.2 soon.
> >>
> >> Thanks for your help!
> >
> > FYI,
> >
> > I have tried clang 2.9 (current SVN trunk)
> > together with CMake from current git.
> >
> > The compiler ID matching works perfectly well!
> >
> > Thanks again!
> >
> > Best regards,
>
> I've been using Clang static analyzer & regular Clang from SVN with
> CMake  for some time and I only have 2 problems with this.
> * When switching compilers some settings are lost, this is an
> annoyance when using ccmake, since I have custom includes that need to
> be entered in manually.

What do you mean with "switching compilers" ?
Installing a new version of clang or changing the compiler in an already 
configured build tree ?

> * For some reason I need to manually add these include paths to my
> CXXFLAGS -I/usr/include/c++/4.5.1
> -I/usr/include/c++/4.5.1/x86_64-unknown-linux-gnu/

Maybe you should put this in the cmake bug tracker.

Alex