[Bug c++/97174] New: out-of-namespace function definition

["wolfgang.roehrl@gi-de.com" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97174

            Bug ID: 97174
           Summary: out-of-namespace function definition
           Product: gcc
           Version: 7.5.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: wolfgang.roehrl@gi-de.com
  Target Milestone: ---

Hi,

I would like to post a bug report for the GNU C/C++ compiler 7.5.0.

We use the compiler to generate code for a PowerPC processor.

Invokation line for the GNU C++ compiler:

ccppc -c -x c++ --std=gnu++17 -Wall -Werror -g -mcpu=e6500 -m32
      -maltivec -mvrsave -ftls-model=local-exec -msdata=sysv
      -fno-common -fno-openmp -mbig -mmultiple -mno-string -misel
      -mstrict-align -fverbose-asm -G 8 -O3
      -I<some include paths>
      -D<some #define's>
      X.CPP -oX.O


// file X.CPP

#include <type_traits>

namespace N
{
  template <typename T>
  typename std::make_unsigned_t<T> conv (T);
}

template <typename T>
long N::conv (T val)
{ return static_cast<long>(val); }


The compiler accepts this code even though function "long N::conv (T)" is not
declared in namespace N. I think this is an illegal out-of-namespace definition
(cf. C++17 standard, 10.3.1.2/2).

With kind regards
W. Roehrl