Re: C++ error

[Laurent Gatto]

Hi Fredrik,

Excellent advice, and I was able to identify the culprit.

Here's a simple reproducible example

$ guix shell --container gcc-toolchain
[env]$ g++ main.cpp
[env]$ exit

$ guix shell --container gcc-toolchain gfortran-toolchain
[env]$ g++ main.cpp
In file included from
/gnu/store/68l504nyvms77jzfg9yf4njiyfbi8gm2-profile/include/c++/bits/move.h:57,
                 from
/gnu/store/68l504nyvms77jzfg9yf4njiyfbi8gm2-profile/include/c++/bits/exception_ptr.h:43,
                 from
/gnu/store/68l504nyvms77jzfg9yf4njiyfbi8gm2-profile/include/c++/exception:153,
                 from
/gnu/store/68l504nyvms77jzfg9yf4njiyfbi8gm2-profile/include/c++/ios:39,
                 from
/gnu/store/68l504nyvms77jzfg9yf4njiyfbi8gm2-profile/include/c++/ostream:38,
                 from
/gnu/store/68l504nyvms77jzfg9yf4njiyfbi8gm2-profile/include/c++/iostream:39,
                 from main.cpp:1:
/gnu/store/68l504nyvms77jzfg9yf4njiyfbi8gm2-profile/include/c++/type_traits:732:26:
error: expected identifier before '(' token
  732 |     _GLIBCXX20_DEPRECATED("use is_standard_layout &&
is_trivial instead")
      |                          ^
/gnu/store/68l504nyvms77jzfg9yf4njiyfbi8gm2-profile/include/c++/type_traits:732:27:
error: expected unqualified-id before string constant
  732 |     _GLIBCXX20_DEPRECATED("use is_standard_layout &&
is_trivial instead")
      |                           ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/gnu/store/68l504nyvms77jzfg9yf4njiyfbi8gm2-profile/include/c++/type_traits:732:27:
error: expected ')' before string constant
  732 |     _GLIBCXX20_DEPRECATED("use is_standard_layout &&
is_trivial instead")
      |                          ~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
      |                           )
/gnu/store/68l504nyvms77jzfg9yf4njiyfbi8gm2-profile/include/c++/type_traits:3154:25:
error: expected unqualified-id before string constant
 3154 |   _GLIBCXX20_DEPRECATED("use is_standard_layout_v &&
is_trivial_v instead")
      |
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/gnu/store/68l504nyvms77jzfg9yf4njiyfbi8gm2-profile/include/c++/type_traits:3154:25:
error: expected ')' before string constant
 3154 |   _GLIBCXX20_DEPRECATED("use is_standard_layout_v &&
is_trivial_v instead")
      |
~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
      |                         )

I also confirmed that I was able to compile that source code by simply
commenting gfortran-toolchain in my system manifest.

Isn't this weird though? What if I need both?


Laurent