[Bug c++/50308] New: __attribute__((deprecated)) incorrectly generates warning in ADL lookup

[Bug c++/50308] New: __attribute__((deprecated)) incorrectly generates warning in ADL lookup

[gd_bugzilla at growndodo dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50308

             Bug #: 50308
           Summary: __attribute__((deprecated)) incorrectly generates
                    warning in ADL lookup
    Classification: Unclassified
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: gd_bugzilla@growndodo.com


void A( int ) __attribute__((deprecated));

namespace B {

struct C {};

void A( C )
{}

}

int main (int argc, const char * argv[])
{
    B::C x;

    // ADL correctly identifies the non-deprecated B::A, but a warning about
the global A is generated anyway
    A( x );

    return 0;
}

[Bug c++/50308] __attribute__((deprecated)) incorrectly generates warning in ADL lookup

[pinskia at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50308

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         Depends on|                            |17729

--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> 2012-02-01 03:13:19 UTC ---
Confirmed.  Looks related to PR 17729.

[Bug c++/50308] __attribute__((deprecated)) incorrectly generates warning in ADL lookup

[pinskia at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50308

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2012-02-01
     Ever Confirmed|0                           |1

[Bug c++/50308] __attribute__((deprecated)) incorrectly generates warning in ADL lookup

[iains at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50308

Iain Sandoe <iains at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |iains at gcc dot gnu.org

--- Comment #2 from Iain Sandoe <iains at gcc dot gnu.org> 2012-02-01 17:57:04 UTC ---
the warning is generated from:
 /GCC/gcc-live-trunk/gcc/cp/semantics.c:3342

the decl is unused on entry to finish_id_expression () ..
.. and marked as used (on line 3306) ... is that expected?

Otherwise, I'd assume that we could guard  line 3342 with say...
  if (TREE_USED (decl) && TREE_DEPRECATED (decl))
    warn_deprecated_use (decl, NULL_TREE);

dunno..
===

(gdb) call debug_tree(node)
 <function_decl 0x421d7800 A
    type <function_type 0x42129f00
        type <void_type 0x4211a720 void VOID
            align 8 symtab 0 alias set -1 canonical type 0x4211a720
            pointer_to_this <pointer_type 0x4211a780>>
        QI
        size <integer_cst 0x4210478c constant 8>
        unit size <integer_cst 0x421047a8 constant 1>
        align 8 symtab 0 alias set -1 canonical type 0x42129f00
        arg-types <tree_list 0x42114588 value <integer_type 0x4211a3c0 int>
            chain <tree_list 0x42114150 value <void_type 0x4211a720 void>>>>
    used public deprecated external QI file ../tests-attr/pr50308-1.C line 1
col 6 align 8 context <translation_unit_decl 0x4211c06c D.1>
    arguments <parm_decl 0x4210e8dc D.2180
        type <integer_type 0x4211a3c0 int public SI
            size <integer_cst 0x421045cc constant 32>
            unit size <integer_cst 0x421045e8 constant 4>
            align 32 symtab 0 alias set -1 canonical type 0x4211a3c0 precision
32 min <integer_cst 0x421048c0 -2147483648> max <integer_cst 0x421048dc
2147483647>
            pointer_to_this <pointer_type 0x4211aae0>>
        SI file ../tests-attr/pr50308-1.C line 1 col 9 size <integer_cst
0x421045cc 32> unit size <integer_cst 0x421045e8 4>
        align 32 context <function_decl 0x421d7800 A>
        arg-type <integer_type 0x4211a3c0 int>>
    full-name "void A(int)"
    chain <function_decl 0x421cee80 __cxa_call_unexpected>>

[Bug c++/50308] __attribute__((deprecated)) incorrectly generates warning in ADL lookup

[iains at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50308

--- Comment #3 from Iain Sandoe <iains at gcc dot gnu.org> 2012-02-02 10:54:44 UTC ---
Created attachment 26551
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=26551
test-case

see PR17729 for an updated patch that also passes for this PR.

Attached, version of the example problem set up as a test-case for the
test-suite.

[Bug c++/50308] __attribute__((deprecated)) incorrectly generates warning in ADL lookup

[iains at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50308

--- Comment #4 from Iain Sandoe <iains at gcc dot gnu.org> 2012-02-02 10:59:40 UTC ---
Comment on attachment 26551
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=26551
test-case

>  // The original reported fault...
>  A (x); // { dg-bogus ".A. is deprecated .declared at .*pr50308-1.C:4." "" }

duh, wrong version attached should be:

  A (x); // { dg-bogus ".void A.int.. is deprecated .declared
at.*pr50308-1.C:4." "" }