[Bug c++/60219] [4.8/4.9 Regression] [c++11] ICE invalid use of variadic template

[Bug c++/60219] [4.8/4.9 Regression] [c++11] ICE invalid use of variadic template

[reichelt at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60219

Volker Reichelt <reichelt at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
      Known to work|                            |4.7.0
   Target Milestone|---                         |4.8.4
      Known to fail|                            |4.8.0, 4.9.0

[Bug c++/60219] New: [4.8/4.9 Regression] [c++11] ICE invalid use of variadic template

[reichelt at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60219

            Bug ID: 60219
           Summary: [4.8/4.9 Regression] [c++11] ICE invalid use of
                    variadic template
           Product: gcc
           Version: 4.9.0
            Status: UNCONFIRMED
          Keywords: diagnostic, ice-on-invalid-code
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: reichelt at gcc dot gnu.org

The following invalid code snippet (compiled with "-std=c++11") triggers
an ICE since GCC 4.8.0:

=============================================
template<typename..., int> void foo();

void bar()
{
  foo<0>;
}
=============================================

bug.cc: In function 'void bar()':
bug.cc:5:9: internal compiler error: tree check: accessed elt 3 of tree_vec
with 2 elts in coerce_template_parms, at cp/pt.c:6857
   foo<0>;
         ^
0xdca805 tree_vec_elt_check_failed(int, int, char const*, int, char const*)
        ../../gcc/gcc/tree.c:9377
0x61aa12 tree_vec_elt_check
        ../../gcc/gcc/tree.h:2899
0x61aa12 coerce_template_parms
        ../../gcc/gcc/cp/pt.c:6857
0x633577 resolve_nondeduced_context(tree_node*)
        ../../gcc/gcc/cp/pt.c:16561
0x6f9907 convert_to_void(tree_node*, impl_conv_void, int)
        ../../gcc/gcc/cp/cvt.c:1244
0x726d8a finish_expr_stmt(tree_node*)
        ../../gcc/gcc/cp/semantics.c:684
0x6ae3e8 cp_parser_statement
        ../../gcc/gcc/cp/parser.c:9473
0x6af1b9 cp_parser_statement_seq_opt
        ../../gcc/gcc/cp/parser.c:9745
0x6af326 cp_parser_compound_statement
        ../../gcc/gcc/cp/parser.c:9699
0x6c34fb cp_parser_function_body
        ../../gcc/gcc/cp/parser.c:18641
0x6c34fb cp_parser_ctor_initializer_opt_and_function_body
        ../../gcc/gcc/cp/parser.c:18677
0x6c7842 cp_parser_function_definition_after_declarator
        ../../gcc/gcc/cp/parser.c:22792
0x6c86e1 cp_parser_function_definition_from_specifiers_and_declarator
        ../../gcc/gcc/cp/parser.c:22704
0x6c86e1 cp_parser_init_declarator
        ../../gcc/gcc/cp/parser.c:16585
0x6c9979 cp_parser_simple_declaration
        ../../gcc/gcc/cp/parser.c:11205
0x6acc63 cp_parser_block_declaration
        ../../gcc/gcc/cp/parser.c:11086
0x6d3f12 cp_parser_declaration
        ../../gcc/gcc/cp/parser.c:10983
0x6d2c08 cp_parser_declaration_seq_opt
        ../../gcc/gcc/cp/parser.c:10869
0x6d44aa cp_parser_translation_unit
        ../../gcc/gcc/cp/parser.c:4014
0x6d44aa c_parse_file()
        ../../gcc/gcc/cp/parser.c:31536
Please submit a full bug report, [etc.]

If I actually try to call foo<0>, I get a broken diagnostic ending in a colon:

==============================================
template<typename..., int> void foo();

void bar()
{
  foo<0>();
}
==============================================

bug.cc: In function 'void bar()':
bug.cc:5:10: error: no matching function for call to 'foo()'
   foo<0>();
          ^
bug.cc:5:10: note: candidate is:
bug.cc:1:33: note: template<class ..., int <anonymous> > void foo()
 template<typename..., int> void foo();
                                 ^
bug.cc:1:33: note:   template argument deduction/substitution failed:

Why?

[Bug c++/60219] [4.8/4.9 Regression] [c++11] ICE invalid use of variadic template

[reichelt at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60219

Volker Reichelt <reichelt at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|4.8.4                       |4.8.3

[Bug c++/60219] [4.8/4.9 Regression] [c++11] ICE invalid use of variadic template

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60219

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2014-02-17
                 CC|                            |jakub at gcc dot gnu.org,
                   |                            |jason at gcc dot gnu.org
            Version|4.9.0                       |4.8.3
     Ever confirmed|0                           |1

--- Comment #1 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Started likely with r190653 (works with r190650, fails with r190662,
coerce_template_parms+resolve_nondeduced_context in backtrace).

[Bug c++/60219] [4.8/4.9 Regression] [c++11] ICE invalid use of variadic template

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60219

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Priority|P3                          |P2

[Bug c++/60219] [4.8/4.9 Regression] [c++11] ICE invalid use of variadic template

[jason at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60219

Jason Merrill <jason at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |ASSIGNED
           Assignee|unassigned at gcc dot gnu.org      |jason at gcc dot gnu.org

[Bug c++/60219] [4.8/4.9 Regression] [c++11] ICE invalid use of variadic template

[jason at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60219

--- Comment #2 from Jason Merrill <jason at gcc dot gnu.org> ---
Author: jason
Date: Fri Feb 21 14:57:00 2014
New Revision: 208003

URL: http://gcc.gnu.org/viewcvs?rev=208003&root=gcc&view=rev
Log:
    PR c++/60219
    * pt.c (coerce_template_parms): Bail if argument packing fails.

Added:
    trunk/gcc/testsuite/g++.dg/cpp0x/variadic150.C
Modified:
    trunk/gcc/cp/ChangeLog
    trunk/gcc/cp/pt.c

[Bug c++/60219] [4.8/4.9 Regression] [c++11] ICE invalid use of variadic template

[jason at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60219

--- Comment #3 from Jason Merrill <jason at gcc dot gnu.org> ---
Author: jason
Date: Fri Feb 21 15:29:25 2014
New Revision: 208007

URL: http://gcc.gnu.org/viewcvs?rev=208007&root=gcc&view=rev
Log:
    PR c++/60219
    * pt.c (coerce_template_parms): Bail if argument packing fails.

Added:
    branches/gcc-4_8-branch/gcc/testsuite/g++.dg/cpp0x/variadic150.C
Modified:
    branches/gcc-4_8-branch/gcc/cp/ChangeLog
    branches/gcc-4_8-branch/gcc/cp/pt.c

[Bug c++/60219] [4.8/4.9 Regression] [c++11] ICE invalid use of variadic template

[jason at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60219

Jason Merrill <jason at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
         Resolution|---                         |FIXED

--- Comment #4 from Jason Merrill <jason at gcc dot gnu.org> ---
Fixed for 4.8.3/4.9.