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* optimization/6692: Tail call optimization does not work for function pointers
@ 2002-05-17 4:26 wlux
0 siblings, 0 replies; 2+ messages in thread
From: wlux @ 2002-05-17 4:26 UTC (permalink / raw)
To: gcc-gnats
>Number: 6692
>Category: optimization
>Synopsis: Tail call optimization does not work for function pointers
>Confidential: no
>Severity: serious
>Priority: medium
>Responsible: unassigned
>State: open
>Class: pessimizes-code
>Submitter-Id: net
>Arrival-Date: Fri May 17 04:26:05 PDT 2002
>Closed-Date:
>Last-Modified:
>Originator: Wolfgang Lux
>Release: gcc version 3.1
>Organization:
>Environment:
Sparc Solaris 2.8
gcc configured with: --program-suffix=-3.1 --enable-languages=c
>Description:
The tail call optimization introduced in Gnu C version 3
does not work if the tail call is made through a function
pointer, e.g.
int exec(int (*f)(int), int n)
{
return (*f)(n);
}
The code generated for this function calls the function
passed via f recursively in a new stack frame instead of
releasing exec's stack frame and jumping to f's entry-point.
>How-To-Repeat:
Compile bug.c with -O2 and run the executable. It crashes
with a Segmentation Fault due to a stack overflow (can be
confirmed with gdb).
>Fix:
>Release-Note:
>Audit-Trail:
>Unformatted:
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^ permalink raw reply [flat|nested] 2+ messages in thread
* Re: optimization/6692: Tail call optimization does not work for function pointers
@ 2003-02-19 10:18 ebotcazou
0 siblings, 0 replies; 2+ messages in thread
From: ebotcazou @ 2003-02-19 10:18 UTC (permalink / raw)
To: gcc-bugs, gcc-prs, nobody, wlux
Synopsis: Tail call optimization does not work for function pointers
State-Changed-From-To: open->closed
State-Changed-By: ebotcazou
State-Changed-When: Wed Feb 19 10:18:45 2003
State-Changed-Why:
The feature has been implemented on the current mainline
(which will likely become gcc 3.4).
http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&database=gcc&pr=6692
^ permalink raw reply [flat|nested] 2+ messages in thread
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2002-05-17 4:26 optimization/6692: Tail call optimization does not work for function pointers wlux
2003-02-19 10:18 ebotcazou
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