[Boost-users] [preprocessor] Undeclared identifier BOOST_PP_IIF_0 under Clang only

Subject: [Boost-users] [preprocessor] Undeclared identifier BOOST_PP_IIF_0 under Clang only
From: Pierre Talbot (ptalbot_at_[hidden])
Date: 2014-04-02 15:48:04

Hi,

I defined a macro using Boost.Preprocessor that compiles and works fine 
under gcc but fails to compile under Clang. The macro is defined here: 
https://github.com/ptal/Boost.Expected/blob/master/include/boost/functional/do_yield.hpp

And the error message follows this message, the file using the macro is 
https://github.com/ptal/Boost.Expected/blob/master/example/monadic_calculator/monadic_calculator.cpp

Thanks for any helps,
Pierre Talbot

Boost.Expected/example/monadic_calculator$ b2
...patience...
...found 1246 targets...
...updating 2 targets...
clang-linux.compile.c++.without-pth 
bin/clang-linux-3.5.0/debug/monadic_calculator.o
monadic_calculator.cpp:141:15: error: use of undeclared identifier 
'BOOST_PP_IIF_0'
     etokens = DO(
               ^
../../include/boost/functional/do_yield.hpp:100:17: note: expanded from 
macro 'DO'
#define DO(...) DO_SEQ(BOOST_PP_VARIADIC_TO_SEQ(__VA_ARGS__))
                 ^
../../include/boost/functional/do_yield.hpp:97:3: note: expanded from 
macro 'DO_SEQ'
   BOOST_PP_SEQ_FOR_EACH_I(DO_ELEM, seq, seq) \
   ^
/usr/local/boost_1_55_0/boost/preprocessor/seq/for_each_i.hpp:27:55: 
note: expanded from macro 'BOOST_PP_SEQ_FOR_EACH_I'
#    define BOOST_PP_SEQ_FOR_EACH_I(macro, data, seq) 
BOOST_PP_FOR((macro, data, seq (nil), 0), BOOST_PP_SEQ_FOR_EACH_I_P, 
BOOST_PP_SEQ_FOR_EACH_I_O, BOOST_PP_SEQ_FOR_EACH_I_M)
                                                       ^
/usr/local/boost_1_55_0/boost/preprocessor/repetition/for.hpp:27:23: 
note: expanded from macro 'BOOST_PP_FOR'
# define BOOST_PP_FOR BOOST_PP_CAT(BOOST_PP_FOR_, 
BOOST_PP_AUTO_REC(BOOST_PP_FOR_P, 256))
                       ^
/usr/local/boost_1_55_0/boost/preprocessor/cat.hpp:22:32: note: expanded 
from macro 'BOOST_PP_CAT'
#    define BOOST_PP_CAT(a, b) BOOST_PP_CAT_I(a, b)
                                ^
/usr/local/boost_1_55_0/boost/preprocessor/cat.hpp:29:34: note: expanded 
from macro 'BOOST_PP_CAT_I'
#    define BOOST_PP_CAT_I(a, b) a ## b
                                  ^
<scratch space>:130:1: note: expanded from here
BOOST_PP_FOR_1
^
/usr/local/boost_1_55_0/boost/preprocessor/repetition/detail/for.hpp:22:37: 
note: expanded from macro 'BOOST_PP_FOR_1'
# define BOOST_PP_FOR_1(s, p, o, m) BOOST_PP_FOR_1_C(BOOST_PP_BOOL(p(2, 
s)), s, p, o, m)
                                     ^
/usr/local/boost_1_55_0/boost/preprocessor/repetition/detail/for.hpp:279:42: 
note: expanded from macro 'BOOST_PP_FOR_1_C'
# define BOOST_PP_FOR_1_C(c, s, p, o, m) BOOST_PP_IIF(c, m, 
BOOST_PP_TUPLE_EAT_2)(2, s) BOOST_PP_IIF(c, BOOST_PP_FOR_2, 
BOOST_PP_TUPLE_EAT_4)(BOOST_PP_EXPR_IIF(c, o)(2, s), p, o, m)
                                          ^
/usr/local/boost_1_55_0/boost/preprocessor/control/iif.hpp:18:37: note: 
expanded from macro 'BOOST_PP_IIF'
#    define BOOST_PP_IIF(bit, t, f) BOOST_PP_IIF_I(bit, t, f)
                                     ^
/usr/local/boost_1_55_0/boost/preprocessor/control/iif.hpp:25:39: note: 
expanded from macro 'BOOST_PP_IIF_I'
#    define BOOST_PP_IIF_I(bit, t, f) BOOST_PP_IIF_ ## bit(t, f)
                                       ^
<scratch space>:136:1: note: expanded from here
BOOST_PP_IIF_0
^