Re: optimization/6647: -O2 (or above) invalid optimization

Re: optimization/6647: -O2 (or above) invalid optimization

[rth]

Synopsis: -O2 (or above) invalid optimization

State-Changed-From-To: analyzed->closed
State-Changed-By: rth
State-Changed-When: Thu May 16 18:56:12 2002
State-Changed-Why:
    Jakub, please just close these after diagnosing not-a-bug.

http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&database=gcc&pr=6647

Re: optimization/6647: -O2 (or above) invalid optimization

[jakub]

Synopsis: -O2 (or above) invalid optimization

State-Changed-From-To: open->analyzed
State-Changed-By: jakub
State-Changed-When: Tue May 14 08:11:43 2002
State-Changed-Why:
    The optimization is valid, the source is not.
    The code does illegal type punning, see info gcc on
    -fstrict-aliasing for details.
    Either rewrite the code using unions, or use -fno-strict-aliasing.

http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&database=gcc&pr=6647

optimization/6647: -O2 (or above) invalid optimization

[skal]

>Number:         6647
>Category:       optimization
>Synopsis:       -O2 (or above) invalid optimization
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Mon May 13 08:26:01 PDT 2002
>Closed-Date:
>Last-Modified:
>Originator:     Pascal Massimino
>Release:        2.96 -> 3.0.4
>Organization:
>Environment:
PIII mobile, linux, redhat 7.1
>Description:
Initialization of a 'float/double' variable occurs
after its address taken and derefenced.
Only occurs with -O2 or above.
>How-To-Repeat:
see attached file bug.cpp
>Fix:

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