[Bug c++/39786] New: Qualified name lookup through different numbers of using directives

[Bug c++/39786] New: Qualified name lookup through different numbers of using directives

[hstong at ca dot ibm dot com]

It appears that qualified name lookup fails to find the correct candidate set
for overload resolution in the test case below.

For the following test case, the symptom is rejects-valid; however, it is
simple
to produce variants for wrong-code and accepts-invalid.

The Comeau online compiler compiles the test case successfully.

ISO/IEC 14882:2003 Sub-clause 3.4.3.2 [namespace.qual] paragraph 2:
===
Given X::m (where X is a user-declared namespace), or given ::m (where X is the
global namespace), let
S be the set of all declarations of m in X and in the transitive closure of all
namespaces nominated by
using-directives in X and its used namespaces, except that using-directives are
ignored in any namespace,
including X, directly containing one or more declarations of m.  No namespace
is searched more than once
in the lookup of a name.  If S is the empty set, the program is ill-formed. 
Otherwise, if S has exactly one
member, or if the context of the reference is a using-declaration (7.3.3), S is
the required set of declarations
of m.  Otherwise if the use of m is not one that allows a unique declaration to
be chosen from S, the program
is ill-formed.
===

We are looking for `f' from the global namespace.  The global namespace does
not directly contain a declaration
of `f'.  There are two namespaces nominated by using-directives in the global
namespace, ::A and ::B.

There are no using-directives in ::A.  ::B does not directly contain a
declaration of `f'.  There is a using-
directive in ::B nominating ::B::C.  There are no using-directives in ::B::C.

S is { ::A::f(char *), ::B::C::f(int) } and overload resolution on the call
`::f(0)' should pick ::B::C::f(int).

### Self-contained source (namelookup.C):
namespace A {
    char (*f(char *p))[13] { return 0; }
}

namespace B {
    namespace C {
        char (*f(int p))[42] { return 0; }
    }
    using namespace C;
}

using namespace B;
using namespace A;

char x[sizeof *::f(0) == 42 ? 1 : -1];


### Command to reproduce:
g++ -c namelookup.C


### Compiler output:
namelookup.C:15: error: size of array x is negative


### g++ -v output:
Using built-in specs.
Target: powerpc64-suse-linux
Configured with: ../configure --prefix=/usr --infodir=/usr/share/info
--mandir=/usr/share/man --libdir=/usr/lib64 --libexecdir=/usr/lib64
--enable-languages=c,c++,objc,fortran,obj-c++,java --enable-checking=release
--with-gxx-include-dir=/usr/include/c++/4.3 --enable-ssp --disable-libssp
--with-bugurl=http://bugs.opensuse.org/ --with-pkgversion='SUSE Linux'
--disable-libgcj --disable-libmudflap --with-slibdir=/lib64 --with-system-zlib
--enable-__cxa_atexit --enable-libstdcxx-allocator=new --disable-libstdcxx-pch
--enable-version-specific-runtime-libs --program-suffix=-4.3
--enable-linux-futex --without-system-libunwind --with-cpu=power4
--enable-secureplt --with-long-double-128 --build=powerpc64-suse-linux
Thread model: posix
gcc version 4.3.2 [gcc-4_3-branch revision 141291] (SUSE Linux)


-- 
           Summary: Qualified name lookup through different numbers of using
                    directives
           Product: gcc
           Version: 4.3.2
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: hstong at ca dot ibm dot com
 GCC build triplet: powerpc64-suse-linux
  GCC host triplet: powerpc64-suse-linux
GCC target triplet: powerpc64-suse-linux


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39786

[Bug c++/39786] [4.3/4.4/4.5 Regression] Qualified name lookup through different numbers of using directives

[rguenth at gcc dot gnu dot org]

------- Comment #1 from rguenth at gcc dot gnu dot org  2009-04-17 09:14 -------
Confirmed.  The code was accepted with 3.3.6


-- 

rguenth at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
     Ever Confirmed|0                           |1
      Known to fail|4.1.2 4.3.2                 |4.1.2 4.3.2 4.5.0
      Known to work|                            |3.3.6
   Last reconfirmed|0000-00-00 00:00:00         |2009-04-17 09:14:10
               date|                            |
            Summary|Qualified name lookup       |[4.3/4.4/4.5 Regression]
                   |through different numbers of|Qualified name lookup
                   |using directives            |through different numbers of
                   |                            |using directives
   Target Milestone|---                         |4.3.4


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39786

[Bug c++/39786] [4.3/4.4/4.5 Regression] Qualified name lookup through different numbers of using directives

[rguenth at gcc dot gnu dot org]

-- 

rguenth at gcc dot gnu dot org changed:

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


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39786

[Bug c++/39786] [4.3/4.4/4.5 Regression] Qualified name lookup through different numbers of using directives

[rguenth at gcc dot gnu dot org]

------- Comment #2 from rguenth at gcc dot gnu dot org  2009-08-04 12:30 -------
GCC 4.3.4 is being released, adjusting target milestone.


-- 

rguenth at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|4.3.4                       |4.3.5


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39786

[Bug c++/39786] [4.3/4.4 Regression] Qualified name lookup through different numbers of using directives

[jason at gcc dot gnu dot org]

------- Comment #3 from jason at gcc dot gnu dot org  2009-11-03 20:45 -------
This test now passes with 4.5, presumably because of

2009-10-28  Jason Merrill  <jason@redhat.com>

        Core issue 812, 861
        * name-lookup.c (set_decl_namespace): Deal properly with inline
        namespaces.
        (qualified_lookup_using_namespace): Overhaul.
        * pt.c (print_candidates): Handle getting an OVERLOAD.

I suppose I could apply the qualified_lookup_using_namespace hunk to 4.3 and
4.4.


-- 

jason at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         AssignedTo|unassigned at gcc dot gnu   |jason at gcc dot gnu dot org
                   |dot org                     |
             Status|NEW                         |ASSIGNED
      Known to fail|4.1.2 4.3.2 4.4.0 4.5.0     |4.1.2 4.3.2 4.4.0
      Known to work|3.3.6                       |3.3.6 4.5.0
   Last reconfirmed|2009-04-17 09:14:10         |2009-11-03 20:45:45
               date|                            |
            Summary|[4.3/4.4/4.5 Regression]    |[4.3/4.4 Regression]
                   |Qualified name lookup       |Qualified name lookup
                   |through different numbers of|through different numbers of
                   |using directives            |using directives


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39786

[Bug c++/39786] [4.3/4.4 Regression] Qualified name lookup through different numbers of using directives

[jason at gcc dot gnu dot org]

------- Comment #4 from jason at gcc dot gnu dot org  2009-11-03 20:52 -------
Subject: Bug 39786

Author: jason
Date: Tue Nov  3 20:52:30 2009
New Revision: 153865

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=153865
Log:
        PR c++/39786
        * g++.dg/lookup/using22.C: New.

Added:
    trunk/gcc/testsuite/g++.dg/lookup/using22.C
Modified:
    trunk/gcc/testsuite/ChangeLog


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39786

[Bug c++/39786] [4.3/4.4 Regression] Qualified name lookup through different numbers of using directives

[jason at gcc dot gnu dot org]

------- Comment #5 from jason at gcc dot gnu dot org  2009-11-03 21:34 -------
Subject: Bug 39786

Author: jason
Date: Tue Nov  3 21:33:55 2009
New Revision: 153872

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=153872
Log:
        PR c++/41876
        * parser.c (cp_parser_exception_declaration): Pass true to
        is_condition parm of cp_parser_type_specifier_seq.
        (cp_parser_omp_for_loop): Likewise.

        PR c++/39786, Core issue 812, 861
        * name-lookup.c (qualified_lookup_using_namespace): Overhaul.


Added:
    branches/gcc-4_4-branch/gcc/testsuite/g++.dg/cpp0x/inline-ns3.C
      - copied unchanged from r153682,
trunk/gcc/testsuite/g++.dg/cpp0x/inline-ns3.C
    branches/gcc-4_4-branch/gcc/testsuite/g++.dg/lookup/using22.C
      - copied unchanged from r153865,
trunk/gcc/testsuite/g++.dg/lookup/using22.C
    branches/gcc-4_4-branch/gcc/testsuite/g++.dg/parse/eh-decl.C
      - copied unchanged from r153864,
trunk/gcc/testsuite/g++.dg/parse/eh-decl.C
Modified:
    branches/gcc-4_4-branch/gcc/cp/ChangeLog
    branches/gcc-4_4-branch/gcc/cp/name-lookup.c
    branches/gcc-4_4-branch/gcc/cp/parser.c
    branches/gcc-4_4-branch/gcc/testsuite/ChangeLog
    branches/gcc-4_4-branch/gcc/testsuite/g++.dg/lookup/using16.C


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39786

[Bug c++/39786] [4.3/4.4 Regression] Qualified name lookup through different numbers of using directives

[jason at gcc dot gnu dot org]

------- Comment #6 from jason at gcc dot gnu dot org  2009-11-03 22:09 -------
Fixed fer 4.4.3, 4.5.0.  I'm not comfortable applying the fix to 4.3 as it
might have unintended side-effects.


-- 

jason at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
         Resolution|                            |FIXED
   Target Milestone|4.3.5                       |4.4.3


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39786