From mboxrd@z Thu Jan  1 00:00:00 1970
From: John Wehle <john@feith.com>
To: shebs@cygnus.com
Cc: gdb-patches@cygnus.com
Subject: Re: GDB 4.17 Patch for stack aligned i386 code
Date: Tue, 09 Mar 1999 18:39:00 -0000
Message-ID: <199903100239.VAA28392@jwlab.FEITH.COM>
X-SW-Source: 1999-03/msg00019.html
Message-ID: <19990309183900.yk7e1AxQZUOUDAfulu5IDxJ2S97d-9hF5N1oj6He8Mk@z>

> I have a bit of anxiety over including it in 4.18 at this
> late date, because of the potential impact on all x86 configs.

Understandable.  What the time frame for the 4.18 release?  Any
idea of the rough plan for a follow up release? My concerns are:

  1) Backtracing through sigtramps on Solaris is somewhat busted without
     my changes (the Solaris library contains functions which don't use
     %ebp as the frame pointer).  For example ... the backtrace from
     gdb.base/a1-selftest.exp (without my patch) shows:

#0  0x80068745 in _libc_sigprocmask ()
#1  0x80098763 in sigprocmask ()
#2  0x8107cb3 in rl_signal_handler (sig=134509072) at signals.c:156
#3  0x800685b1 in _sigacthandler ()
#4  <signal handler called>
#5  0x800682b8 in _libc_read ()
#6  0x8101ef9 in rl_getc (stream=0x800a9ad4) at readline.c:3123
#7  0x80ffa5b in rl_read_key () at readline.c:578

     The correct backtrace is:

#0  0x80068745 in _libc_sigprocmask ()
#1  0x80098763 in sigprocmask ()
#2  0x8107fe7 in rl_signal_handler (sig=134509096) at signals.c:156
#3  0x800685b1 in _sigacthandler ()
#4  <signal handler called>
#5  0x800682b8 in _libc_read ()
#6  0x80098b33 in read ()
#7  0x810222d in rl_getc (stream=0x81639a0) at readline.c:3123
#8  0x80ffd8f in rl_read_key () at readline.c:578

  2) The egcs patch to eliminate the frame pointer by default on the
     x86 can't be installed until there's debugger support.

I certainly agree that this is a sizable change to the x86 support and
realize that it may not make sense for 4.18 if you guys are close to a
release.  Drat. :-)

-- John
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