objc/7035: Wrong code in byte-swapping routine generated

[marco@technoboredom.net]

>Number:         7035
>Category:       objc
>Synopsis:       Wrong code in byte-swapping routine generated
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          wrong-code
>Submitter-Id:   net
>Arrival-Date:   Fri Jun 14 16:36:00 PDT 2002
>Closed-Date:
>Last-Modified:
>Originator:     marco@technoboredom.net
>Release:        unknown-1.0
>Organization:
>Environment:
marco@gontscharow:~ > uname -a
Linux gontscharow 2.4.4-4GB #1 Sat Jun 23 05:26:59 GMT 2001 i686 unknown

marco@gontscharow:~ > gcc -v
Reading specs from /usr/lib/gcc-lib/i686-pc-linux-gnu/3.1/specs
Configured with: ../gcc-3.1/configure --prefix=/usr --enable-shared --enable-threads=pthreads --enable-languages=ada,c,c++,f77,java,objc : (reconfigured) ../gcc-3.1/configure --prefix=/usr --enable-shared --enable-threads=pthreads --enable-languages=c,c++,f77,java,objc : (reconfigured) ../gcc-3.1/configure --prefix=/usr --enable-shared --enable-threads=posix --enable-languages=c,c++,f77,java,objc
Thread model: posix
gcc version 3.1
>Description:
The Objective-C compiler generates wrong code in GNUstep's byteswapping-routines with the -O2 switch. 

This is most likely a duplicate to #6834, however I have a shorter testcase (23 lines) here. 
>How-To-Repeat:
marco@gontscharow:~/tmp > gcc -O2 bla.m -o bla
marco@gontscharow:~/tmp > ./bla
GSU(0)=191
marco@gontscharow:~/tmp > gcc bla.m -o bla
marco@gontscharow:~/tmp > ./bla
GSU(0)=0

-- 
The result should be 0 (=byteswap of 0). Compiling this code as a C-programm also returns the correct value, no matter which optimization was selected.
>Fix:

>Release-Note:
>Audit-Trail:
>Unformatted:
----gnatsweb-attachment----
Content-Type: application/octet-stream; name="bla.m"
Content-Transfer-Encoding: base64
Content-Disposition: attachment; filename="bla.m"

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