[boost] Fwd: [clang] clang-cl expansion of macros

Subject: [boost] Fwd: [clang] clang-cl expansion of macros
From: degski (degski_at_[hidden])
Date: 2017-04-29 07:58:55

On 16 April 2016 at 17:58, Edward Diener <eldiener_at_[hidden]> wrote:

> What I strongly suspect will finally happen is that clang will not fix
> these emulation problems because they are too tricky and numerous to do.
> Instead they will probably declare that their emulation is good enough for
> the majority of preprocessor constructs and that Boost PP, which pushes the
> preprocessor to its limits, is not meant to work with their flawed VC++
> emulation. I hope I am wrong about that supposition, but having spent much
> time in Boost PP and Boost VMD trying to workaround VC++ non-standard
> preprocessor behavior I can envision that having to code "down" to that
> behavior in numerous complicated instances will be too much time consuming
> work for the clang developers who have chosen to work with VC++
> preprocessor emulation.
>

I've successfully built boost-1.64 with VC1410 (from the developer command
prompt). Trying to use boost with a project using Clang 4.0.0 (both the
LLVM and C2 backends) gives me the following PP error messages:

1>------ Rebuild All started: Project: test, Configuration: Debug x64 ------
1>  In file included from test.cpp:16:
1>  In file included from z:\vc\x64\include\boost/filesystem.hpp:16:
1>  In file included from z:\vc\x64\include\boost/filesystem/path.hpp:28:
1>  In file included from z:\vc\x64\include\boost/iterat
or/iterator_facade.hpp:12:
1>  In file included from z:\vc\x64\include\boost/iterat
or/interoperable.hpp:11:
1>  In file included from z:\vc\x64\include\boost/mpl/or.hpp:43:
1>  In file included from z:\vc\x64\include\boost/mpl/au
x_/include_preprocessed.hpp:37:
1>z:\vc\x64\include\boost/mpl/aux_/preprocessed/plain/or.hpp(59,7): error :
too many arguments provided to function-like macro invocation
1>        2
1>        ^
1>  z:\vc\x64\include\boost/preprocessor/facilities/expand.hpp(26,10):
note: macro 'BOOST_PP_EXPAND_I' defined here
1>  # define BOOST_PP_EXPAND_I(x) x
1>           ^
1>  In file included from test.cpp:16:
1>  In file included from z:\vc\x64\include\boost/filesystem.hpp:16:
1>  In file included from z:\vc\x64\include\boost/filesystem/path.hpp:28:
1>  In file included from z:\vc\x64\include\boost/iterat
or/iterator_facade.hpp:12:
1>  In file included from z:\vc\x64\include\boost/iterat
or/interoperable.hpp:11:
1>  In file included from z:\vc\x64\include\boost/mpl/or.hpp:43:
1>  In file included from z:\vc\x64\include\boost/mpl/au
x_/include_preprocessed.hpp:37:
1>z:\vc\x64\include\boost/mpl/aux_/preprocessed/plain/or.hpp(58,1): error :
expected a qualified name after 'typename'
1>  BOOST_MPL_AUX_NA_SPEC2(
1>  ^
1>  z:\vc\x64\include\boost/mpl/aux_/na_spec.hpp(166,44):  note: expanded
from macro 'BOOST_MPL_AUX_NA_SPEC2'
1>  #define BOOST_MPL_AUX_NA_SPEC2(i, j, name) \
1>                                             ^
1>  z:\vc\x64\include\boost/mpl/aux_/na_spec.hpp(64,11):  note: expanded
from macro '\
1>
1>  BOOST_MPL_AUX_NA_SPEC_MAIN'
1>            BOOST_MPL_PP_PARAMS(i, typename T) \
1>            ^
1>  z:\vc\x64\include\boost/mpl/aux_/preprocessor/params.hpp(58,11):  note:
expanded from macro 'BOOST_MPL_PP_PARAMS'
1>          , BOOST_MPL_PP_AUX_PARAM_FUNC \
1>            ^
1>  In file included from test.cpp:16:
1>  In file included from z:\vc\x64\include\boost/filesystem.hpp:16:
1>  In file included from z:\vc\x64\include\boost/filesystem/path.hpp:28:
1>  In file included from z:\vc\x64\include\boost/iterat
or/iterator_facade.hpp:12:
1>  In file included from z:\vc\x64\include\boost/iterat
or/interoperable.hpp:11:
1>  In file included from z:\vc\x64\include\boost/mpl/or.hpp:43:
1>  In file included from z:\vc\x64\include\boost/mpl/au
x_/include_preprocessed.hpp:37:
1>z:\vc\x64\include\boost/mpl/aux_/preprocessed/plain/or.hpp(58,1): error :
expected ',' or '>' in template-parameter-list

Up till now I was using a hacked boost-1.62. So in order to see what would
happen, I also built boost-1.63. Apart from a small change in
type_with_alignment.hpp (adding a ckeck for _MSC_VER not to exist if
__clang__ does exist in line 87), boost-1.63 compiles without a problem (no
specific (relevant to the emulation) command line parameters).

Is there a macro I should define or is there something else I should set/do
in order to use boost-1.64 with Clang 4.0.0 on windows? Any other
suggestions?

degski
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