[Bug c++/61736] New: Conditional expression yields wrong value category

[Bug c++/61736] New: Conditional expression yields wrong value category

[kaballo86 at hotmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61736

            Bug ID: 61736
           Summary: Conditional expression yields wrong value category
           Product: gcc
           Version: 4.10.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: kaballo86 at hotmail dot com

The following snippet results in a compilation error: invalid initialization of
non-const reference of type ‘int&’ from an rvalue of type ‘int’:

    int* foo(){ return nullptr; }
    int& bar(){ return foo() != nullptr ? *foo() : throw 0; } // error

    int main() {
      int& ref = bar();
    }

According to [expr.cond]/2:
> If either the second or the third operand has type void, one of the following shall hold:
>  — The second or the third operand (but not both) is a (possibly parenthesized) throw-expression (15.1); the result is of the type and value category of the other.

The value category of the conditional expression would be that of `*foo()`,
which should be an lvalue and bind to `int&`.
>From gcc-bugs-return-455786-listarch-gcc-bugs=gcc.gnu.org@gcc.gnu.org Mon Jul 07 14:17:56 2014
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From: "paolo at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c++/58898] Adding default template argument to class template with "most vexing parse" causes compile error
Date: Mon, 07 Jul 2014 14:17:00 -0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?idX898

--- Comment #2 from paolo at gcc dot gnu.org <paolo at gcc dot gnu.org> ---
Author: paolo
Date: Mon Jul  7 14:17:17 2014
New Revision: 212331

URL: https://gcc.gnu.org/viewcvs?rev!2331&root=gcc&view=rev
Log:
2014-07-07  Paolo Carlini  <paolo.carlini@oracle.com>

    PR c++/58898
    * g++.dg/parse/pr58898.C: New.

Added:
    trunk/gcc/testsuite/g++.dg/parse/pr58898.C
Modified:
    trunk/gcc/testsuite/ChangeLog

[Bug c++/61736] Conditional expression yields wrong value category

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61736

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2014-10-02
     Ever confirmed|0                           |1

[Bug c++/61736] Conditional expression yields wrong value category

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61736

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

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

--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Dup of bug 64372.  Fixed in GCC 10+.

*** This bug has been marked as a duplicate of bug 64372 ***