Boost 1.60 any.hpp error: 'if_' in namespace 'boost::mpl' does not name a template type

[Thomas Milotti <thomas.milotti@…>]

Linux 3.19.0-51-generic #58-Ubuntu SMP Fri Feb 26 21:22:26 UTC 2016 x86_64 x86_64 x86_64 GNU/Linux Ubuntu 15.04

Boost 1.60

#include <iostream> #include <boost/any.hpp>

int main() {

boost::any a = 1; std::cout << boost::any_cast<int>(a) << '\n'; a = 3.14; std::cout << boost::any_cast<double>(a) << '\n'; a = true; std::cout << std::boolalpha << boost::any_cast<bool>(a) << '\n';

}

This code generates a compilation error:

/usr/include/boost/any.hpp: In function ‘ValueType boost::any_cast(boost::any&)’: /usr/include/boost/any.hpp:292:52: error: ‘if_’ in namespace ‘boost::mpl’ does not name a template type

typedef BOOST_DEDUCED_TYPENAME boost::mpl::if_<

/usr/include/boost/any.hpp:292:55: error: expected unqualified-id before ‘<’ token

typedef BOOST_DEDUCED_TYPENAME boost::mpl::if_<

/usr/include/boost/any.hpp:298:28: error: ‘ref_type’ does not name a type

return static_cast<ref_type>(*result);

[Antony Polukhin]

Looks like this was fixed in ​ed7cac4e. Are you sure that Boost. 1.60 is used on your system? Does the fix line exist in your header?

[Christopher Arndt]

A similar bug exists in classic_utility.hpp (resp. boost/spirit/home/classic/utility.hpp), which also fails to include if.hpp`.

Checking for header boost/spirit/include/classic_utility.hpp
==>
#include <boost/spirit/include/classic_utility.hpp>

int main(int argc, char **argv) {
        (void)argc; (void)argv;
        return 0;
}

<==
[1/2] Compiling ESC[32mbuild/.conf_check_f294e83272b96d2356ef0156052d5b3c/test.cppESC[0m

['/usr/lib/ccache/bin/g++', '-std=c++11', '-march=x86-64', '-mtune=generic', '-O2', '-pipe', '-fstack-protector', '-D_FORTIFY_SOURCE=2', '-DVERSION="1.0.0"', '-DHAVE_BOOST_SPIRIT_INCLUDE_CLASSIC_DYNAMIC_HPP=1', '-DHAVE_BOOST_SPIRIT_INCLUDE_CLASSIC_CORE_HPP=1', '-DHAVE_BOOST_SPIRIT_INCLUDE_CLASSIC_PARSE_TREE_HPP=1', '../test.cpp', '-c', '-o', '/home/chris/src/arch/aur/ttl2c-git/src/ttl2c/build/.conf_check_f294e83272b96d2356ef0156052d5b3c/testbuild/test.cpp.1.o']
err: In file included from /usr/include/boost/spirit/home/classic/utility.hpp:30:0,
                 from /usr/include/boost/spirit/include/classic_utility.hpp:11,
                 from ../test.cpp:1:
/usr/include/boost/spirit/home/classic/utility/loops.hpp:269:35: error: 'if_' in namespace 'boost::mpl' does not name a template type
             typedef typename mpl::if_<
                                   ^~~
/usr/include/boost/spirit/home/classic/utility/loops.hpp:269:38: error: expected unqualified-id before '<' token
             typedef typename mpl::if_<
                                      ^

[Antony Polukhin]

Added a test in ​c8a2c96a. The issue is not reproducable.