optimization/834: gcc badly optimizes ptr incrementation due to cast in lvalue

[Daniel dot Diaz at inria dot fr]

>Number:         834
>Category:       optimization
>Synopsis:       gcc badly optimizes ptr incrementation due to cast in lvalue
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          pessimizes-code
>Submitter-Id:   net
>Arrival-Date:   Fri Nov 17 10:16:01 PST 2000
>Closed-Date:
>Last-Modified:
>Originator:     INRIA FRANCE
>Release:        Reading specs from /usr/lib/gcc-lib/i586-mandrake-linux/2.95.3/specs gcc version 2.95.3 19991030 (prerelease)
>Organization:
>Environment:
Linux lima.univ-paris1.fr 2.2.15-4mdk #1 Wed May 10 15:31:30 CEST 2000 i686 unknown
>Description:
Hi, I'm the author of GNU-Prolog (a Prolog compiler).
I use gcc intensively and found that gcc misses an optimization 
in presence of a cast.
>How-To-Repeat:
see information in attached file problem.c
>Fix:
move the cast in an inner level as shown in Push_Good function.
>Release-Note:
>Audit-Trail:
>Unformatted:
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