gcj/161: Source parser miscompiles loops when using "-O"

[bryce@albatross.co.nz]

>Number:         161
>Category:       gcj
>Synopsis:       Source parser miscompiles loops when using "-O"
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    apbianco
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Sat Mar 04 23:00:00 PST 2000
>Closed-Date:
>Last-Modified:
>Originator:     Bryce McKinlay
>Release:        gcc version 2.96 20000303 (experimental), also 2.95.2
>Organization:
>Environment:
Redhat 6.1
>Description:
The presence of certain combinations of "continue" 
and "break" within loops results in incorrect runtime 
behavior and/or crashes when compiling from source with 
"-O".

>How-To-Repeat:
Compile and run the attached test case. In this example, 
the crashes seem to occur on the 'break' statement after
the loop completes and one or more 'continue's have already
been executed, however this is a simplification of a more
complex loop in some of my code where I'm seeing all kinds
of bizzare behavior - not just on 'break' - but the 
presence of 'continue' definatly seems to be a factor.
>Fix:

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