[Bug c++/12135] New: [3.4 regression] spurious "int ._0" in error message

["reichelt at gcc dot gnu dot org" <gcc-bugzilla at gcc dot gnu dot org>]

PLEASE REPLY TO gcc-bugzilla@gcc.gnu.org ONLY, *NOT* gcc-bugs@gcc.gnu.org.

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=12135

           Summary: [3.4 regression] spurious "int ._0" in error message
           Product: gcc
           Version: 3.4
            Status: UNCONFIRMED
          Keywords: diagnostic
          Severity: minor
          Priority: P2
         Component: c++
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: reichelt at gcc dot gnu dot org
                CC: gcc-bugs at gcc dot gnu dot org

Compiling the invalid code snippet

--------------------------------------------
inline template <int> void foo () {}
--------------------------------------------

with mainline, I get the following error message:

  bug.cc:1: error: expected unqualified-id
  bug.cc:1: error: ISO C++ forbids declaration of `type name' with no type
  bug.cc:1: error: abstract declarator `int' used as declaration
  bug.cc:1: error: explicit instantiation of non-template `int ._0'
  bug.cc:1: error: expected `;'

which is bogus. The worst part is "int ._0" which is nowhere to be
seen in the code. The rest isn't very helpful either.

Previous versions of gcc just gave a simple

  bug.cc:1: error: parse error before `<' token

which isn't very elaborate, but not as confusing as mainline's message.


Btw, 3.3 branch issues an ICE when compiling the following code
(one can use any name of a builtin instead of abort):

--------------------------------------------
inline template <int> void foo () {}
void abort ();
--------------------------------------------

The error message then is:

  bug.cc:1: error: parse error before `<' token
  bug.cc:3: internal compiler error: in lookup_template_function, at
cp/pt.c:         4002
  Please submit a full bug report, [etc.]

But since this is an error-recovery problem which is fixed on mainline,
there's nothing more to do about the ICE.