c/1624: incorrect stack adjustment with -fomit-frame-pointer on x86

[drepper@redhat.com]

>Number:         1624
>Category:       c
>Synopsis:       incorrect stack adjustment with -fomit-frame-pointer on x86
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Thu Jan 11 17:26:00 PST 2001
>Closed-Date:
>Last-Modified:
>Originator:     Ulrich Drepper
>Release:        unknown-1.0
>Organization:
>Environment:
Linux x86
>Description:
The appended code crashes if it is compiled with

   -O3 -fomit-frame-pointer

It works fine without -fomit-frame-pointer.

The problem is that the return address is taken from the wrong stack slot.  There is one more value left on the stack (the content of %ebx) which means the main() returns to somewhere in the data area (where %ebx points to).
>How-To-Repeat:
gcc -O3 -fomit-frame-pointer -o t tst-setjmp.i
./t
>Fix:

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