[Bug c++/37281] bad code generation with enum and -m32

["pinskia at gmail dot com" <gcc-bugzilla@gcc.gnu.org>]

------- Comment #1 from pinskia at gmail dot com  2008-08-29 16:39 -------
Subject: Re:   New: bad code generation with enum and -m32

This code is undefined as the value of  32 is outside the range of the  
enum.

Sent from my iPhone

On Aug 29, 2008, at 9:29, "gmorin1 at bloomberg dot net"
<gcc-bugzilla@gcc.gnu.org 
 > wrote:

> This is a copy of a Debian report that I made (I thought I might as  
> well report
> it directly here too): http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=496965
>
> g++ generates bad code for this program on an amd64 machine.  It  
> works with
> fine in 64-bit and with older versions of gcc.
>
> #include <stdlib.h>
> struct MyTypes {
>    enum Type {
>        NOVALUE = 1,
>        VALUE   = 30,
>        VALUE2 = 31,
>        VALUE3 = -3
>    };
>
>    static bool isValue(MyTypes::Type value);
> };
>
> bool MyTypes::isValue(MyTypes::Type value)
> {
>    switch (value) {
>      case MyTypes::VALUE:
>      case MyTypes::VALUE2:
>      case MyTypes::VALUE3: {
>        return true;
>      }
>      default: {
>        return false;
>      }
>    }
> }
>
> int main(int argc, char *argv[])
> {
>    if (true == MyTypes::isValue(MyTypes::Type(32))) {
>        abort();
>    }
>    return 0;
> }
>
> guillaum@canard:~$ g++ -m32 -Wall -o e enumtest.cpp
> guillaum@canard:~$ ./e
> Aborted
> guillaum@canard:~$ g++ -Wall -o e enumtest.cpp
> guillaum@canard:~$ ./e
> guillaum@canard:~$ g++-4.2 -m32 -Wall -o e enumtest.cpp
> guillaum@canard:~$ ./e
> guillaum@canard:~$ g++-4.1 -m32 -Wall -o e enumtest.cpp
> guillaum@canard:~$ ./e
>
> It works with -O2 though (not -O1):
> guillaum@canard:~$ g++ -O2 -m32 -Wall -o e enumtest.cpp
> guillaum@canard:~$ ./e
>
>
> -- System Information:
> Debian Release: lenny/sid
>  APT prefers testing
>  APT policy: (990, 'testing'), (500, 'unstable')
> Architecture: amd64 (x86_64)
>
>
> -- 
>           Summary: bad code generation with enum and -m32
>           Product: gcc
>           Version: 4.3.1
>            Status: UNCONFIRMED
>          Severity: normal
>          Priority: P3
>         Component: c++
>        AssignedTo: unassigned at gcc dot gnu dot org
>        ReportedBy: gmorin1 at bloomberg dot net
>
>
> http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37281
>


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37281