c++/7209: Faulty array dereferencing

c++/7209: Faulty array dereferencing

[jdbuiso]

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>Number:         7209
>Category:       c++
>Synopsis:       Faulty array dereferencing
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          wrong-code
>Submitter-Id:   net
>Arrival-Date:   Thu Jul 04 13:06:00 PDT 2002
>Closed-Date:
>Last-Modified:
>Originator:     Jornand de Buisonjé
>Release:        3.1
>Organization:
>Environment:
DOS (DJGPP) and Linux, both x86.
>Description:
Dereferencing an array using a ternary operation (?:) and a function return value as indices can give faulty (and variable) results. In the example code one or more of the asserts can fail (depending on the optimization level), but only when compiling as C++.
>How-To-Repeat:

>Fix:
Doing the ternary operation and/or function call before the array indexing solves (avoids) the problem.
>Release-Note:
>Audit-Trail:
>Unformatted:
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Re: c++/7209: Faulty array dereferencing

[nathan]

Synopsis: Faulty array dereferencing

State-Changed-From-To: analyzed->closed
State-Changed-By: nathan
State-Changed-When: Tue Oct 22 02:10:22 2002
State-Changed-Why:
    this will appear in 3.2.1 & 3.3
    2002-10-22  Nathan Sidwell  <nathan@codesourcery.com>
    
    	PR c++/7209
    	* fold_const.c (fold_binary_op_with_conditional_arg): Always
    	build compound_expr if we used save_expr.

http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&database=gcc&pr=7209

Re: c++/7209: Faulty array dereferencing

[nathan]

Synopsis: Faulty array dereferencing

Responsible-Changed-From-To: unassigned->nathan
Responsible-Changed-By: nathan
Responsible-Changed-When: Wed Oct 16 14:57:08 2002
Responsible-Changed-Why:
    fixing

http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&database=gcc&pr=7209

Re: c++/7209: Faulty array dereferencing

[nathan]

Synopsis: Faulty array dereferencing

State-Changed-From-To: open->analyzed
State-Changed-By: nathan
State-Changed-When: Sat Sep 14 13:11:37 2002
State-Changed-Why:
    confirmed, regression 

http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&database=gcc&pr=7209