[Bug c++/65110] New: Does not accept multi-argument template in member initialization

[Bug c++/65110] New: Does not accept multi-argument template in member initialization

[stanshebs at earthlink dot net]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65110

            Bug ID: 65110
           Summary: Does not accept multi-argument template in member
                    initialization
           Product: gcc
           Version: 4.8.2
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: stanshebs at earthlink dot net

The following snippet generates a host of complaints, presumably connected to
ambiguity of template argument list vs initializer list:

template<typename, typename> struct C { int n; };
struct D { int k = C<D, D>().n; };

$ cc -Wall -std=c++11 demo.cc
demo.cc:2:25: error: expected ‘;’ at end of member declaration
 struct D { int k = C<D, D>().n; };
                         ^
demo.cc:2:26: error: expected unqualified-id before ‘>’ token
 struct D { int k = C<D, D>().n; };
                          ^
demo.cc:2:22: error: wrong number of template arguments (1, should be 2)
 struct D { int k = C<D, D>().n; };
                      ^
demo.cc:1:37: error: provided for ‘template<class, class> struct C’
 template<typename, typename> struct C { int n; };
                                     ^

This occurs for both 4.8 and current trunk; current Clang accepts without any
complaints.

(Google ref: b/19213572)
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From: "froydnj at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug middle-end/65111] New: null checks on pointers created from references not optimized away
Date: Wed, 18 Feb 2015 19:29:00 -0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?ide111

            Bug ID: 65111
           Summary: null checks on pointers created from references not
                    optimized away
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: middle-end
          Assignee: unassigned at gcc dot gnu.org
          Reporter: froydnj at gcc dot gnu.org

Compiling the C++ code:

#include <new>

void init(int& p)
{
  new (&p) float(3.14f);
}

yields (GCC 4.9.1):

_Z4initRi:
    testq    %rdi, %rdi
    je    .L1
    movl    $0x4048f5c3, (%rdi)
.L1:
    rep ret

Compiling the equivalent code with clang (3.5 and 3.6-prerelease) yields:

_Z4initRi:                              # @_Z4initRi
    movl    $1078523331, (%rdi)     # imm = 0x4048F5C3
    retq

because clang has determined that &p cannot be null.

[Bug c++/65110] Does not accept multi-argument template in member initialization

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65110

Jonathan Wakely <redi at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |RESOLVED
         Resolution|---                         |DUPLICATE

--- Comment #1 from Jonathan Wakely <redi at gcc dot gnu.org> ---
This is http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#325 and so
a dup of PR 52595

*** This bug has been marked as a duplicate of bug 52595 ***