[Bug c++/48536] New: C++0x Automatic Enumerator Incrementation is not compliant with Clause 7.2/5

[Bug c++/48536] New: C++0x Automatic Enumerator Incrementation is not compliant with Clause 7.2/5

[shaw.john.r at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48536

           Summary: C++0x Automatic Enumerator Incrementation is not
                    compliant with Clause 7.2/5
           Product: gcc
           Version: 4.5.2
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: shaw.john.r@gmail.com


The enumerations defined below are well-formed C++0x, but g++, with C++0x
extensions enabled, still treats #1 as an overflow error.

Note: Comeau C/C++ 4.3.10.1 with C++0x extensions enabled reports no errors.

#include <climits>
//
// g++ version 4.5.2 and below
//
// Compiler options:
//    -std=c++0x
//    -std=gnu++0x
// non-compliant error message:
//    "error: overflow in enumeration values"
//
// According to C++ draft N1905 (2005) and above / Clause 7.2/5
// The following enumeration is well-formed.
//
enum Enum_Inc  { EI_1=UINT_MAX, EI_2 }; // #1

// The above should be equivalent to the following
enum Enum_Inc2 { FI_1=UINT_MAX, FI_2=FI_1+1 }; // #2

[Bug c++/48536] C++0x Automatic Enumerator Incrementation is not compliant with Clause 7.2/5

[redi at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48536

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

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

--- Comment #1 from Jonathan Wakely <redi at gcc dot gnu.org> 2011-05-03 20:00:08 UTC ---
I'm not sure #1 is equivalent to #2, but I think they should both be
well-formed.
Jason, can you confirm?

[Bug c++/48536] C++0x Automatic Enumerator Incrementation is not compliant with Clause 7.2/5

[jason at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48536

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2011.05.03 20:34:19
     Ever Confirmed|0                           |1

--- Comment #2 from Jason Merrill <jason at gcc dot gnu.org> 2011-05-03 20:34:19 UTC ---
Agreed.

"Otherwise the type of the initializing value is the same as the type of the
initializing value of the preceding enumerator unless the incremented value is
not representable in that type, in which case the type is an unspecified
integral type sufficient to contain the incremented value. If no such type
exists, the program is ill-formed."

Instead of complaining about overflow, we should adjust the type of EI_2.

But I'm pretty sure #1 and #2 are not equivalent because the initializer for
FI_2 wraps to 0.

[Bug c++/48536] [C++0x] Automatic Enumerator Incrementation is not compliant with Clause 7.2/5

[jason at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48536

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

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

[Bug c++/48536] [C++0x] Automatic Enumerator Incrementation is not compliant with Clause 7.2/5

[jason at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48536

--- Comment #3 from Jason Merrill <jason at gcc dot gnu.org> 2011-05-26 02:23:04 UTC ---
Author: jason
Date: Thu May 26 02:23:02 2011
New Revision: 174258

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=174258
Log:
    PR c++/48536
    * decl.c (build_enumerator): If incremented enumerator won't fit in
    previous integral type, find one it will fit in.

Added:
    trunk/gcc/testsuite/g++.dg/cpp0x/enum17.C
Modified:
    trunk/gcc/cp/ChangeLog
    trunk/gcc/cp/decl.c
    trunk/gcc/testsuite/ChangeLog
    trunk/gcc/testsuite/g++.old-deja/g++.jason/rfg10.C

[Bug c++/48536] [C++0x] Automatic Enumerator Incrementation is not compliant with Clause 7.2/5

[jason at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48536

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
         Resolution|                            |FIXED
   Target Milestone|---                         |4.7.0

--- Comment #4 from Jason Merrill <jason at gcc dot gnu.org> 2011-05-26 03:08:22 UTC ---
Fixed for 4.7.

[Bug c++/48536] [C++0x] Automatic Enumerator Incrementation is not compliant with Clause 7.2/5

[redi at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48536

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |dnetserrspam at gmail dot
                   |                            |com

--- Comment #5 from Jonathan Wakely <redi at gcc dot gnu.org> 2011-09-28 18:25:47 UTC ---
*** Bug 50559 has been marked as a duplicate of this bug. ***