[Bug c++/37281] New: bad code generation with enum and -m32
Andrew Thomas Pinski
pinskia@gmail.com
Fri Aug 29 16:39:00 GMT 2008
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
>
More information about the Gcc-bugs
mailing list