but it does not set/add the required library
> Am 24.11.2016 um 22:01 schrieb Craig Scott <craig.sc...@crascit.com>:
>
> You might also need to set CMAKE_CXX_EXTENSIONS to OFF (it's ON by default).
> This controls which c++ library is linked for some compilers, with clang and
> gcc being two cases where it does this. You may also find this article about
> the related CMake variables and commands to be of interest.
>
>> On Fri, Nov 25, 2016 at 5:43 AM, Roman Wüger <roman.wue...@gmx.at> wrote:
>> It is working now, after I added -lc++ to CMAKE_REQUIRED_LIBRARIES before
>> the check_cxx_source_compiles() call.
>>
>> Shouldn't this be done by CMAKE_CXX_STANDARD?
>>
>> Best Regards
>> Roman
>>
>>> Am 24.11.2016 um 19:08 schrieb Roman Wüger <roman.wue...@gmx.at>:
>>>
>>> Hello,
>>>
>>>
>>>
>>> If I use a small piece of code which uses <regex>, then it fails with
>>> check_cxx_source_compiles. If I copy the piece of code into a file and run
>>> the following on the command line, then it works:
>>>
>>>
>>>
>>> clang++ main.cpp -std=c++14 -stdlib=libc++
>>>
>>>
>>>
>>> Here is the piece of code:
>>>
>>>
>>>
>>> #include <regex>
>>>
>>> #include <string>
>>>
>>>
>>>
>>> int main() {
>>>
>>> const std::string text = "Roses are #ff0000, other flowers have other
>>> colors.";
>>>
>>> const std::regex pattern("#([a-f0-9]{2})");
>>>
>>>
>>>
>>> std::smatch match;
>>>
>>> std::regex_search(text, match, pattern);
>>>
>>>
>>>
>>> return 0;
>>>
>>> }
>>>
>>>
>>>
>>> I use this code in CMake as a platform check as followed:
>>>
>>>
>>>
>>> # C++11 Regular Expression
>>>
>>> set(CMAKE_REQUIRED_FLAGS "${CMAKE_CXX_FLAGS}")
>>>
>>> check_cxx_source_compiles(
>>>
>>> "#include <regex>
>>>
>>> #include <string>
>>>
>>>
>>>
>>> int main() {
>>>
>>> const std::string text = \"Roses are #ff0000, other flowers have
>>> other colors.\";
>>>
>>> const std::regex pattern(\"#([a-f0-9]{2})\");
>>>
>>>
>>>
>>> std::smatch match;
>>>
>>> std::regex_search(text, match, pattern);
>>>
>>>
>>>
>>> return 0;
>>>
>>> }"
>>>
>>> HAVE_CXX11_REGULAR_EXPRESSIONS
>>>
>>> )
>>>
>>> set(CMAKE_REQUIRED_FLAGS "")
>>>
>>>
>>>
>>> CMakeFiles/CMakeError.log shows:
>>>
>>>
>>>
>>> Undefined symbols for architecture x86_64:
>>>
>>> "std::__1::basic_string<char, std::__1::char_traits<char>,
>>> std::__1::allocator<char> >::compare(char const*) const", referenced from:
>>>
>>> std::__1::basic_regex<char, std::__1::regex_traits<char>
>>> >::__start_matching_list(bool) in src.o
>>>
>>> "std::__1::__vector_base_common<true>::__throw_length_error() const",
>>> referenced from:
>>>
>>> std::__1::vector<std::__1::sub_match<char const*>,
>>> std::__1::allocator<std::__1::sub_match<char const*> > >::assign(unsigned
>>> long, std::__1::sub_match<char const*> const&) in src.o
>>>
>>> std::__1::vector<std::__1::sub_match<char const*>,
>>> std::__1::allocator<std::__1::sub_match<char const*> > >::allocate(unsigned
>>> long) in src.o
>>>
>>> void std::__1::vector<std::__1::__state<char>,
>>> std::__1::allocator<std::__1::__state<char> >
>>> >::__push_back_slow_path<std::__1::__state<char>
>>> >(std::__1::__state<char>&&) in src.o
>>>
>>> std::__1::vector<std::__1::sub_match<char const*>,
>>> std::__1::allocator<std::__1::sub_match<char const*> > >::__append(unsigned
>>> long, std::__1::sub_match<char const*> const&) in src.o
>>>
>>> std::__1::vector<std::__1::pair<unsigned long, char const*>,
>>> std::__1::allocator<std::__1::pair<unsigned long, char const*> >
>>> >::__append(unsigned long) in src.o
>>>
>>> std::__1::vector<std::__1::pair<unsigned long, char const*>,
>>> std::__1::allocator<std::__1::pair<unsigned long, char const*> >
>>> >::allocate(unsigned long) in src.o
>>>
>>> void std::__1::vector<char, std::__1::allocator<char>
>>> >::__push_back_slow_path<char>(char&&) in src.o
>>>
>>> ...
>>>
>>> "std::__1::__basic_string_common<true>::__throw_length_error() const",
>>> referenced from:
>>>
>>> std::__1::enable_if<__is_forward_iterator<char*>::value, void>::type
>>> std::__1::basic_string<char, std::__1::char_traits<char>,
>>> std::__1::allocator<char> >::__init<char*>(char*, char*) in src.o
>>>
>>> std::__1::enable_if<__is_forward_iterator<char const*>::value,
>>> void>::type std::__1::basic_string<char, std::__1::char_traits<char>,
>>> std::__1::allocator<char> >::__init<char const*>(char const*, char const*)
>>> in src.o
>>>
>>>
>>> std::__1::enable_if<__is_forward_iterator<std::__1::__wrap_iter<char*>
>>> >::value, void>::type std::__1::basic_string<char,
>>> std::__1::char_traits<char>, std::__1::allocator<char>
>>> >::__init<std::__1::__wrap_iter<char*> >(std::__1::__wrap_iter<char*>,
>>> std::__1::__wrap_iter<char*>) in src.o
>>>
>>>
>>> "std::__1::__match_any_but_newline<char>::__exec(std::__1::__state<char>&)
>>> const", referenced from:
>>>
>>> vtable for std::__1::__match_any_but_newline<char> in src.o
>>>
>>> "std::__1::locale::name() const", referenced from:
>>>
>>> std::__1::basic_regex<char, std::__1::regex_traits<char>
>>> >::__start_matching_list(bool) in src.o
>>>
>>> "std::__1::locale::use_facet(std::__1::locale::id&) const", referenced
>>> from:
>>>
>>> std::__1::regex_traits<char>::__init() in src.o
>>>
>>>
>>> "std::__1::regex_error::regex_error(std::__1::regex_constants::error_type)",
>>> referenced from:
>>>
>>> char const* std::__1::basic_regex<char, std::__1::regex_traits<char>
>>> >::__parse<char const*>(char const*, char const*) in src.o
>>>
>>> char const* std::__1::basic_regex<char, std::__1::regex_traits<char>
>>> >::__parse_basic_reg_exp<char const*>(char const*, char const*) in src.o
>>>
>>> char const* std::__1::basic_regex<char, std::__1::regex_traits<char>
>>> >::__parse_extended_reg_exp<char const*>(char const*, char const*) in src.o
>>>
>>> char const* std::__1::basic_regex<char, std::__1::regex_traits<char>
>>> >::__parse_assertion<char const*>(char const*, char const*) in src.o
>>>
>>> char const* std::__1::basic_regex<char, std::__1::regex_traits<char>
>>> >::__parse_atom<char const*>(char const*, char const*) in src.o
>>>
>>> char const* std::__1::basic_regex<char, std::__1::regex_traits<char>
>>> >::__parse_ERE_dupl_symbol<char const*>(char const*, char const*,
>>> std::__1::__owns_one_state<char>*, unsigned int, unsigned int) in src.o
>>>
>>> bool std::__1::basic_regex<char, std::__1::regex_traits<char>
>>> >::__match_at_start_ecma<std::__1::allocator<std::__1::sub_match<char
>>> const*> > >(char const*, char const*, std::__1::match_results<char const*,
>>> std::__1::allocator<std::__1::sub_match<char const*> > >&,
>>> std::__1::regex_constants::match_flag_type, bool) const in src.o
>>>
>>> ...
>>>
>>> "std::__1::regex_error::~regex_error()", referenced from:
>>>
>>> char const* std::__1::basic_regex<char, std::__1::regex_traits<char>
>>> >::__parse<char const*>(char const*, char const*) in src.o
>>>
>>> char const* std::__1::basic_regex<char, std::__1::regex_traits<char>
>>> >::__parse_basic_reg_exp<char const*>(char const*, char const*) in src.o
>>>
>>> char const* std::__1::basic_regex<char, std::__1::regex_traits<char>
>>> >::__parse_extended_reg_exp<char const*>(char const*, char const*) in src.o
>>>
>>> char const* std::__1::basic_regex<char, std::__1::regex_traits<char>
>>> >::__parse_assertion<char const*>(char const*, char const*) in src.o
>>>
>>> char const* std::__1::basic_regex<char, std::__1::regex_traits<char>
>>> >::__parse_atom<char const*>(char const*, char const*) in src.o
>>>
>>> char const* std::__1::basic_regex<char, std::__1::regex_traits<char>
>>> >::__parse_ERE_dupl_symbol<char const*>(char const*, char const*,
>>> std::__1::__owns_one_state<char>*, unsigned int, unsigned int) in src.o
>>>
>>> bool std::__1::basic_regex<char, std::__1::regex_traits<char>
>>> >::__match_at_start_ecma<std::__1::allocator<std::__1::sub_match<char
>>> const*> > >(char const*, char const*, std::__1::match_results<char const*,
>>> std::__1::allocator<std::__1::sub_match<char const*> > >&,
>>> std::__1::regex_constants::match_flag_type, bool) const in src.o
>>>
>>> ...
>>>
>>> "std::__1::basic_string<char, std::__1::char_traits<char>,
>>> std::__1::allocator<char> >::__init(char const*, unsigned long)",
>>> referenced from:
>>>
>>> _main in src.o
>>>
>>> "std::__1::basic_string<char, std::__1::char_traits<char>,
>>> std::__1::allocator<char> >::__init(unsigned long, char)", referenced from:
>>>
>>> std::__1::__bracket_expression<char, std::__1::regex_traits<char>
>>> >::__exec(std::__1::__state<char>&) const in src.o
>>>
>>> "std::__1::basic_string<char, std::__1::char_traits<char>,
>>> std::__1::allocator<char> >::reserve(unsigned long)", referenced from:
>>>
>>> std::__1::basic_string<char, std::__1::char_traits<char>,
>>> std::__1::allocator<char> >
>>> std::__1::regex_traits<char>::__lookup_collatename<char*>(char*, char*,
>>> char) const in src.o
>>>
>>> char const* std::__1::basic_regex<char, std::__1::regex_traits<char>
>>> >::__parse_collating_symbol<char const*>(char const*, char const*,
>>> std::__1::basic_string<char, std::__1::char_traits<char>,
>>> std::__1::allocator<char> >&) in src.o
>>>
>>> std::__1::basic_string<char, std::__1::char_traits<char>,
>>> std::__1::allocator<char> >
>>> std::__1::regex_traits<char>::__lookup_collatename<char const*>(char
>>> const*, char const*, char) const in src.o
>>>
>>> "std::__1::basic_string<char, std::__1::char_traits<char>,
>>> std::__1::allocator<char> >::basic_string(std::__1::basic_string<char,
>>> std::__1::char_traits<char>, std::__1::allocator<char> > const&)",
>>> referenced from:
>>>
>>> char const* std::__1::basic_regex<char, std::__1::regex_traits<char>
>>> >::__parse_equivalence_class<char const*>(char const*, char const*,
>>> std::__1::__bracket_expression<char, std::__1::regex_traits<char> >*) in
>>> src.o
>>>
>>> void std::__1::vector<std::__1::basic_string<char,
>>> std::__1::char_traits<char>, std::__1::allocator<char> >,
>>> std::__1::allocator<std::__1::basic_string<char,
>>> std::__1::char_traits<char>, std::__1::allocator<char> > >
>>> >::__push_back_slow_path<std::__1::basic_string<char,
>>> std::__1::char_traits<char>, std::__1::allocator<char> >
>>> const&>(std::__1::basic_string<char, std::__1::char_traits<char>,
>>> std::__1::allocator<char> > const&&&) in src.o
>>>
>>> "std::__1::basic_string<char, std::__1::char_traits<char>,
>>> std::__1::allocator<char> >::~basic_string()", referenced from:
>>>
>>> _main in src.o
>>>
>>> std::__1::basic_regex<char, std::__1::regex_traits<char>
>>> >::__start_matching_list(bool) in src.o
>>>
>>> std::__1::__bracket_expression<char, std::__1::regex_traits<char>
>>> >::__exec(std::__1::__state<char>&) const in src.o
>>>
>>> std::__1::__vector_base<std::__1::basic_string<char,
>>> std::__1::char_traits<char>, std::__1::allocator<char> >,
>>> std::__1::allocator<std::__1::basic_string<char,
>>> std::__1::char_traits<char>, std::__1::allocator<char> > >
>>> >::~__vector_base() in src.o
>>>
>>> std::__1::pair<std::__1::basic_string<char,
>>> std::__1::char_traits<char>, std::__1::allocator<char> >,
>>> std::__1::basic_string<char, std::__1::char_traits<char>,
>>> std::__1::allocator<char> > >::~pair() in src.o
>>>
>>> std::__1::basic_string<char, std::__1::char_traits<char>,
>>> std::__1::allocator<char> >
>>> std::__1::regex_traits<char>::transform<char*>(char*, char*) const in src.o
>>>
>>> std::__1::basic_string<char, std::__1::char_traits<char>,
>>> std::__1::allocator<char> >
>>> std::__1::regex_traits<char>::__lookup_collatename<char*>(char*, char*,
>>> char) const in src.o
>>>
>>> ...
>>>
>>> "std::__1::basic_string<char, std::__1::char_traits<char>,
>>> std::__1::allocator<char> >::operator=(std::__1::basic_string<char,
>>> std::__1::char_traits<char>, std::__1::allocator<char> > const&)",
>>> referenced from:
>>>
>>> std::__1::basic_string<char, std::__1::char_traits<char>,
>>> std::__1::allocator<char> >
>>> std::__1::regex_traits<char>::__lookup_collatename<char*>(char*, char*,
>>> char) const in src.o
>>>
>>> std::__1::basic_string<char, std::__1::char_traits<char>,
>>> std::__1::allocator<char> >
>>> std::__1::regex_traits<char>::__lookup_collatename<char const*>(char
>>> const*, char const*, char) const in src.o
>>>
>>> "std::__1::basic_string<char, std::__1::char_traits<char>,
>>> std::__1::allocator<char> >::operator=(char)", referenced from:
>>>
>>> char const* std::__1::basic_regex<char, std::__1::regex_traits<char>
>>> >::__parse_character_escape<char const*>(char const*, char const*,
>>> std::__1::basic_string<char, std::__1::char_traits<char>,
>>> std::__1::allocator<char> >*) in src.o
>>>
>>> char const* std::__1::basic_regex<char, std::__1::regex_traits<char>
>>> >::__parse_expression_term<char const*>(char const*, char const*,
>>> std::__1::__bracket_expression<char, std::__1::regex_traits<char> >*) in
>>> src.o
>>>
>>> char const* std::__1::basic_regex<char, std::__1::regex_traits<char>
>>> >::__parse_class_escape<char const*>(char const*, char const*,
>>> std::__1::basic_string<char, std::__1::char_traits<char>,
>>> std::__1::allocator<char> >&, std::__1::__bracket_expression<char,
>>> std::__1::regex_traits<char> >*) in src.o
>>>
>>> char const* std::__1::basic_regex<char, std::__1::regex_traits<char>
>>> >::__parse_awk_escape<char const*>(char const*, char const*,
>>> std::__1::basic_string<char, std::__1::char_traits<char>,
>>> std::__1::allocator<char> >*) in src.o
>>>
>>> "std::__1::__get_classname(char const*, bool)", referenced from:
>>>
>>> unsigned int std::__1::regex_traits<char>::__lookup_classname<char
>>> const*>(char const*, char const*, bool, char) const in src.o
>>>
>>> "std::__1::__shared_weak_count::__add_shared()", referenced from:
>>>
>>> std::__1::basic_regex<char, std::__1::regex_traits<char>
>>> >::basic_regex(std::__1::basic_regex<char, std::__1::regex_traits<char> >
>>> const&) in src.o
>>>
>>> "std::__1::__shared_weak_count::__release_shared()", referenced from:
>>>
>>> std::__1::shared_ptr<std::__1::__empty_state<char> >::~shared_ptr()
>>> in src.o
>>>
>>> "std::__1::__shared_weak_count::~__shared_weak_count()", referenced from:
>>>
>>> std::__1::__shared_ptr_pointer<std::__1::__empty_state<char>*,
>>> std::__1::default_delete<std::__1::__empty_state<char> >,
>>> std::__1::allocator<std::__1::__empty_state<char> >
>>> >::~__shared_ptr_pointer() in src.o
>>>
>>> "std::__1::__get_collation_name(char const*)", referenced from:
>>>
>>> std::__1::basic_string<char, std::__1::char_traits<char>,
>>> std::__1::allocator<char> >
>>> std::__1::regex_traits<char>::__lookup_collatename<char*>(char*, char*,
>>> char) const in src.o
>>>
>>> std::__1::basic_string<char, std::__1::char_traits<char>,
>>> std::__1::allocator<char> >
>>> std::__1::regex_traits<char>::__lookup_collatename<char const*>(char
>>> const*, char const*, char) const in src.o
>>>
>>> "std::__1::ctype<char>::id", referenced from:
>>>
>>> std::__1::regex_traits<char>::__init() in src.o
>>>
>>> "std::__1::locale::locale(std::__1::locale const&)", referenced from:
>>>
>>>
>>> std::__1::regex_traits<char>::regex_traits(std::__1::regex_traits<char>
>>> const&) in src.o
>>>
>>> std::__1::basic_regex<char, std::__1::regex_traits<char>
>>> >::__start_matching_list(bool) in src.o
>>>
>>> "std::__1::locale::locale()", referenced from:
>>>
>>> std::__1::regex_traits<char>::regex_traits() in src.o
>>>
>>> "std::__1::locale::~locale()", referenced from:
>>>
>>> std::__1::regex_traits<char>::~regex_traits() in src.o
>>>
>>> std::__1::regex_traits<char>::regex_traits() in src.o
>>>
>>> std::__1::basic_regex<char, std::__1::regex_traits<char>
>>> >::__start_matching_list(bool) in src.o
>>>
>>> "std::__1::collate<char>::id", referenced from:
>>>
>>> std::__1::regex_traits<char>::__init() in src.o
>>>
>>> "typeinfo for std::__1::regex_error", referenced from:
>>>
>>> char const* std::__1::basic_regex<char, std::__1::regex_traits<char>
>>> >::__parse<char const*>(char const*, char const*) in src.o
>>>
>>> char const* std::__1::basic_regex<char, std::__1::regex_traits<char>
>>> >::__parse_basic_reg_exp<char const*>(char const*, char const*) in src.o
>>>
>>> char const* std::__1::basic_regex<char, std::__1::regex_traits<char>
>>> >::__parse_extended_reg_exp<char const*>(char const*, char const*) in src.o
>>>
>>> char const* std::__1::basic_regex<char, std::__1::regex_traits<char>
>>> >::__parse_assertion<char const*>(char const*, char const*) in src.o
>>>
>>> char const* std::__1::basic_regex<char, std::__1::regex_traits<char>
>>> >::__parse_atom<char const*>(char const*, char const*) in src.o
>>>
>>> char const* std::__1::basic_regex<char, std::__1::regex_traits<char>
>>> >::__parse_ERE_dupl_symbol<char const*>(char const*, char const*,
>>> std::__1::__owns_one_state<char>*, unsigned int, unsigned int) in src.o
>>>
>>> bool std::__1::basic_regex<char, std::__1::regex_traits<char>
>>> >::__match_at_start_ecma<std::__1::allocator<std::__1::sub_match<char
>>> const*> > >(char const*, char const*, std::__1::match_results<char const*,
>>> std::__1::allocator<std::__1::sub_match<char const*> > >&,
>>> std::__1::regex_constants::match_flag_type, bool) const in src.o
>>>
>>> ...
>>>
>>> "typeinfo for std::__1::__shared_weak_count", referenced from:
>>>
>>> typeinfo for
>>> std::__1::__shared_ptr_pointer<std::__1::__empty_state<char>*,
>>> std::__1::default_delete<std::__1::__empty_state<char> >,
>>> std::__1::allocator<std::__1::__empty_state<char> > > in src.o
>>>
>>> "vtable for std::__1::__shared_count", referenced from:
>>>
>>> std::__1::shared_ptr<std::__1::__empty_state<char>
>>> >::shared_ptr<std::__1::__empty_state<char>
>>> >(std::__1::__empty_state<char>*,
>>> std::__1::enable_if<is_convertible<std::__1::__empty_state<char>*,
>>> std::__1::__empty_state<char>*>::value,
>>> std::__1::shared_ptr<std::__1::__empty_state<char> >::__nat>::type) in src.o
>>>
>>> NOTE: a missing vtable usually means the first non-inline virtual member
>>> function has no definition.
>>>
>>> "vtable for std::__1::__shared_weak_count", referenced from:
>>>
>>> std::__1::shared_ptr<std::__1::__empty_state<char>
>>> >::shared_ptr<std::__1::__empty_state<char>
>>> >(std::__1::__empty_state<char>*,
>>> std::__1::enable_if<is_convertible<std::__1::__empty_state<char>*,
>>> std::__1::__empty_state<char>*>::value,
>>> std::__1::shared_ptr<std::__1::__empty_state<char> >::__nat>::type) in src.o
>>>
>>> NOTE: a missing vtable usually means the first non-inline virtual member
>>> function has no definition.
>>>
>>> ld: symbol(s) not found for architecture x86_64
>>>
>>> clang: error: linker command failed with exit code 1 (use -v to see
>>> invocation)
>>>
>>>
>>>
>>> ** BUILD FAILED **
>>>
>>>
>>>
>>> Did I forget something?
>>>
>>>
>>>
>>> Thanks in advance
>>>
>>>
>>>
>>> Best Regards
>>>
>>> Roman
>>>
>>> --
>>>
>>> Powered by www.kitware.com
>>>
>>> Please keep messages on-topic and check the CMake FAQ at:
>>> http://www.cmake.org/Wiki/CMake_FAQ
>>>
>>> Kitware offers various services to support the CMake community. For more
>>> information on each offering, please visit:
>>>
>>> CMake Support: http://cmake.org/cmake/help/support.html
>>> CMake Consulting: http://cmake.org/cmake/help/consulting.html
>>> CMake Training Courses: http://cmake.org/cmake/help/training.html
>>>
>>> Visit other Kitware open-source projects at
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>>>
>>> Follow this link to subscribe/unsubscribe:
>>> http://public.kitware.com/mailman/listinfo/cmake-developers
>>
>> --
>>
>> Powered by www.kitware.com
>>
>> Please keep messages on-topic and check the CMake FAQ at:
>> http://www.cmake.org/Wiki/CMake_FAQ
>>
>> Kitware offers various services to support the CMake community. For more
>> information on each offering, please visit:
>>
>> CMake Support: http://cmake.org/cmake/help/support.html
>> CMake Consulting: http://cmake.org/cmake/help/consulting.html
>> CMake Training Courses: http://cmake.org/cmake/help/training.html
>>
>> Visit other Kitware open-source projects at
>> http://www.kitware.com/opensource/opensource.html
>>
>> Follow this link to subscribe/unsubscribe:
>> http://public.kitware.com/mailman/listinfo/cmake-developers
>
>
>
> --
> Craig Scott
> Melbourne, Australia
> https://crascit.com
--
Powered by www.kitware.com
Please keep messages on-topic and check the CMake FAQ at:
http://www.cmake.org/Wiki/CMake_FAQ
Kitware offers various services to support the CMake community. For more
information on each offering, please visit:
CMake Support: http://cmake.org/cmake/help/support.html
CMake Consulting: http://cmake.org/cmake/help/consulting.html
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Visit other Kitware open-source projects at
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