[Bug c++/65514] New: Initializing a non-static const data member of a template class from a static const data member of another template class results in errors in certain situations

[nilschrbrause at googlemail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65514

            Bug ID: 65514
           Summary: Initializing a non-static const data member of a
                    template class from a static const data member of
                    another template class results in errors in certain
                    situations
           Product: gcc
           Version: 4.9.2
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: nilschrbrause at googlemail dot com

Created attachment 35093
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=35093&action=edit
Test source

% g++ -v
Using built-in specs.
COLLECT_GCC=g++
COLLECT_LTO_WRAPPER=/usr/lib/gcc/x86_64-unknown-linux-gnu/4.9.2/lto-wrapper
Target: x86_64-unknown-linux-gnu
Configured with: /build/gcc-multilib/src/gcc-4.9-20150304/configure
--prefix=/usr --libdir=/usr/lib --libexecdir=/usr/lib --mandir=/usr/share/man
--infodir=/usr/share/info --with-bugurl=https://bugs.archlinux.org/
--enable-languages=c,c++,ada,fortran,go,lto,objc,obj-c++ --enable-shared
--enable-threads=posix --with-system-zlib --enable-__cxa_atexit
--disable-libunwind-exceptions --enable-clocale=gnu --disable-libstdcxx-pch
--disable-libssp --enable-gnu-unique-object --enable-linker-build-id
--enable-cloog-backend=isl --enable-lto --enable-plugin
--enable-install-libiberty --with-linker-hash-style=gnu --enable-multilib
--disable-werror --enable-checking=release
Thread model: posix
gcc version 4.9.2 20150304 (prerelease) (GCC)

% g++ -std=c++11 test.cpp
test.cpp:12:25: error: expected ‘;’ at end of member declaration
   const int is = add<1, x>::is;
                         ^
test.cpp:12:25: error: declaration of ‘const int add1<x>::x’
test.cpp:8:11: error:  shadows template parm ‘int x’
 template <int x> 
           ^
test.cpp:12:26: error: expected unqualified-id before ‘>’ token
   const int is = add<1, x>::is;
                          ^
test.cpp:12:22: error: wrong number of template arguments (1, should be 2)
   const int is = add<1, x>::is;
                      ^
test.cpp:2:7: error: provided for ‘template<int x, int y> class add’
 class add 
       ^

Source code is attached.

The error vanishes, when:
- a 'static' is added: const static int is = add<1, x>::is;
- the '1' and the 'x' are reversed: const int is = add<x, 1>::is;
- the RHS is enclosed in paranthesis: const int is = (add<1, x>::is);