c/3328: wrong code with Optimization '-O'

[Andreas.Krakowczyk@fujitsu-siemens.com]

>Number:         3328
>Category:       c
>Synopsis:       wrong code with Optimization '-O'
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Thu Jun 21 07:26:01 PDT 2001
>Closed-Date:
>Last-Modified:
>Originator:     Andreas Krakowczyk
>Release:        gcc-3.0
>Organization:
>Environment:
sun-sparc-solaris2.8
>Description:
Strange behaviour of code, works without optimization, but not with '-O'.
Rearranging code leads to not working at all or always working.
>How-To-Repeat:
gcc -O bug5.c && ./a.out
>Fix:

>Release-Note:
>Audit-Trail:
>Unformatted:
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