Re: problem with changeset fa917f1f0faf

[Ben Abbott]

> On Aug 10, 2016, at 8:37 PM, Carnë Draug <address@hidden> wrote:
> 
> On 11 August 2016 at 00:47, Ben Abbott <address@hidden> wrote:
>> Carne,
>> 
>> I think I’m seeing an error associated with the change below.
>> 
>>        http://hg.savannah.gnu.org/hgweb/octave/rev/fa917f1f0faf
>> 
>> [...]
>> 
>> liboctave/array/MatrixType.cc:530:23: error: assigning to 'double' from 
>> incompatible type 'complex<double>'
>>                    d = std::conj (d);
>>                      ^ ~~~~~~~~~~~~~
> 
> How does your compiler handles this?
> 
>    #include <iostream>
>    #include <complex>
>    #include <typeinfo>
> 
>    int main()
>    {
>      std::cout << typeid (std::conj (double (5.0))).name() << std::endl;
>    }
> 
> If you get back a complex number, the issue is discussed on DR 1137 [1].
> You should get back d for double.  I only found this DR number because
> it's refered on the GCC implementation of conj.
> 
> Carnë
> 
> [1] https://lwg.github.io/issues/lwg-defects.html#1137

I’m out of my element … I placed those lines in foo.cc and compiled using 
Apple’s clang

clang foo.cc
Undefined symbols for architecture x86_64:
  "std::__1::locale::use_facet(std::__1::locale::id&) const", referenced from:
      std::__1::basic_ostream<char, std::__1::char_traits<char> >& 
std::__1::endl<char, std::__1::char_traits<char> 
>(std::__1::basic_ostream<char, std::__1::char_traits<char> >&) in foo-7e13c7.o
      std::__1::basic_ostream<char, std::__1::char_traits<char> >& 
std::__1::__put_character_sequence<char, std::__1::char_traits<char> 
>(std::__1::basic_ostream<char, std::__1::char_traits<char> >&, char const*, 
unsigned long) in foo-7e13c7.o
  "std::__1::ios_base::getloc() const", referenced from:
      std::__1::basic_ostream<char, std::__1::char_traits<char> >& 
std::__1::endl<char, std::__1::char_traits<char> 
>(std::__1::basic_ostream<char, std::__1::char_traits<char> >&) in foo-7e13c7.o
      std::__1::basic_ostream<char, std::__1::char_traits<char> >& 
std::__1::__put_character_sequence<char, std::__1::char_traits<char> 
>(std::__1::basic_ostream<char, std::__1::char_traits<char> >&, char const*, 
unsigned long) in foo-7e13c7.o
  "std::__1::basic_string<char, std::__1::char_traits<char>, 
std::__1::allocator<char> >::__init(unsigned long, char)", referenced from:
      std::__1::ostreambuf_iterator<char, std::__1::char_traits<char> > 
std::__1::__pad_and_output<char, std::__1::char_traits<char> 
>(std::__1::ostreambuf_iterator<char, std::__1::char_traits<char> >, char 
const*, char const*, char const*, std::__1::ios_base&, char) in foo-7e13c7.o
  "std::__1::basic_string<char, std::__1::char_traits<char>, 
std::__1::allocator<char> >::~basic_string()", referenced from:
      std::__1::ostreambuf_iterator<char, std::__1::char_traits<char> > 
std::__1::__pad_and_output<char, std::__1::char_traits<char> 
>(std::__1::ostreambuf_iterator<char, std::__1::char_traits<char> >, char 
const*, char const*, char const*, std::__1::ios_base&, char) in foo-7e13c7.o
  "std::__1::basic_ostream<char, std::__1::char_traits<char> >::put(char)", 
referenced from:
      std::__1::basic_ostream<char, std::__1::char_traits<char> >& 
std::__1::endl<char, std::__1::char_traits<char> 
>(std::__1::basic_ostream<char, std::__1::char_traits<char> >&) in foo-7e13c7.o
  "std::__1::basic_ostream<char, std::__1::char_traits<char> >::flush()", 
referenced from:
      std::__1::basic_ostream<char, std::__1::char_traits<char> >& 
std::__1::endl<char, std::__1::char_traits<char> 
>(std::__1::basic_ostream<char, std::__1::char_traits<char> >&) in foo-7e13c7.o
  "std::__1::basic_ostream<char, std::__1::char_traits<char> 
>::sentry::sentry(std::__1::basic_ostream<char, std::__1::char_traits<char> 
>&)", referenced from:
      std::__1::basic_ostream<char, std::__1::char_traits<char> >& 
std::__1::__put_character_sequence<char, std::__1::char_traits<char> 
>(std::__1::basic_ostream<char, std::__1::char_traits<char> >&, char const*, 
unsigned long) in foo-7e13c7.o
  "std::__1::basic_ostream<char, std::__1::char_traits<char> 
>::sentry::~sentry()", referenced from:
      std::__1::basic_ostream<char, std::__1::char_traits<char> >& 
std::__1::__put_character_sequence<char, std::__1::char_traits<char> 
>(std::__1::basic_ostream<char, std::__1::char_traits<char> >&, char const*, 
unsigned long) in foo-7e13c7.o
  "std::__1::cout", referenced from:
      _main in foo-7e13c7.o
  "std::__1::ctype<char>::id", referenced from:
      std::__1::basic_ostream<char, std::__1::char_traits<char> >& 
std::__1::endl<char, std::__1::char_traits<char> 
>(std::__1::basic_ostream<char, std::__1::char_traits<char> >&) in foo-7e13c7.o
      std::__1::basic_ostream<char, std::__1::char_traits<char> >& 
std::__1::__put_character_sequence<char, std::__1::char_traits<char> 
>(std::__1::basic_ostream<char, std::__1::char_traits<char> >&, char const*, 
unsigned long) in foo-7e13c7.o
  "std::__1::locale::~locale()", referenced from:
      std::__1::basic_ostream<char, std::__1::char_traits<char> >& 
std::__1::endl<char, std::__1::char_traits<char> 
>(std::__1::basic_ostream<char, std::__1::char_traits<char> >&) in foo-7e13c7.o
      std::__1::basic_ostream<char, std::__1::char_traits<char> >& 
std::__1::__put_character_sequence<char, std::__1::char_traits<char> 
>(std::__1::basic_ostream<char, std::__1::char_traits<char> >&, char const*, 
unsigned long) in foo-7e13c7.o
  "std::__1::ios_base::__set_badbit_and_consider_rethrow()", referenced from:
      std::__1::basic_ostream<char, std::__1::char_traits<char> >& 
std::__1::__put_character_sequence<char, std::__1::char_traits<char> 
>(std::__1::basic_ostream<char, std::__1::char_traits<char> >&, char const*, 
unsigned long) in foo-7e13c7.o
  "std::__1::ios_base::clear(unsigned int)", referenced from:
      std::__1::basic_ostream<char, std::__1::char_traits<char> >& 
std::__1::__put_character_sequence<char, std::__1::char_traits<char> 
>(std::__1::basic_ostream<char, std::__1::char_traits<char> >&, char const*, 
unsigned long) in foo-7e13c7.o
  "std::terminate()", referenced from:
      ___clang_call_terminate in foo-7e13c7.o
  "vtable for __cxxabiv1::__class_type_info", referenced from:
      typeinfo for std::__1::complex<double> in foo-7e13c7.o
  NOTE: a missing vtable usually means the first non-inline virtual member 
function has no definition.
  "___cxa_begin_catch", referenced from:
      std::__1::basic_ostream<char, std::__1::char_traits<char> >& 
std::__1::__put_character_sequence<char, std::__1::char_traits<char> 
>(std::__1::basic_ostream<char, std::__1::char_traits<char> >&, char const*, 
unsigned long) in foo-7e13c7.o
      ___clang_call_terminate in foo-7e13c7.o
  "___cxa_end_catch", referenced from:
      std::__1::basic_ostream<char, std::__1::char_traits<char> >& 
std::__1::__put_character_sequence<char, std::__1::char_traits<char> 
>(std::__1::basic_ostream<char, std::__1::char_traits<char> >&, char const*, 
unsigned long) in foo-7e13c7.o
  "___gxx_personality_v0", referenced from:
      std::__1::basic_ostream<char, std::__1::char_traits<char> >& 
std::__1::endl<char, std::__1::char_traits<char> 
>(std::__1::basic_ostream<char, std::__1::char_traits<char> >&) in foo-7e13c7.o
      std::__1::basic_ostream<char, std::__1::char_traits<char> >& 
std::__1::__put_character_sequence<char, std::__1::char_traits<char> 
>(std::__1::basic_ostream<char, std::__1::char_traits<char> >&, char const*, 
unsigned long) in foo-7e13c7.o
      std::__1::ostreambuf_iterator<char, std::__1::char_traits<char> > 
std::__1::__pad_and_output<char, std::__1::char_traits<char> 
>(std::__1::ostreambuf_iterator<char, std::__1::char_traits<char> >, char 
const*, char const*, char const*, std::__1::ios_base&, char) in foo-7e13c7.o
      Dwarf Exception Unwind Info (__eh_frame) in foo-7e13c7.o
ld: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)

Ben