From: imp@bsdimp.com (M. Warner Losh)
Subject: [TUHS] PDP-8
Date: Sat, 02 Oct 2010 15:39:11 -0600 (MDT) [thread overview]
Message-ID: <20101002.153911.710852003685317415.imp@bsdimp.com> (raw)
In-Reply-To: <20101002210346.GE27937@bitmover.com>
In message: <20101002210346.GE27937 at bitmover.com>
Larry McVoy <lm at bitmover.com> writes:
: > > If you could look at the stack frames and give me a stack trace
: > > that's more or less the same thing.
: >
: > (gdb) bt
: >
: > The real question is not to get a stack trace, but to analyse it.
:
: Hmm, we seem to have a different view. I like people who can write
: the gdb bt code, not run it. This isn't an imaginary thing, one of
: my guys showed up one day with his own hand rolled backtrace that we
: ended up putting in our product for support.
:
: The advantage of his, over the following hack we had before, was that
: it worked when no gdb was installed (windows):
:
: void
: gdb_backtrace(void)
: {
: FILE *f;
: char *cmd;
:
: unless (getenv("_BK_BACKTRACE")) return;
: unless ((f = efopen("BK_TTYPRINTF")) ||
: (f = fopen(DEV_TTY, "w"))) {
: f = stderr;
: }
: cmd = aprintf("gdb -batch -ex backtrace '%s/bk' %u 1>&%d 2>&%d",
: bin, getpid(), fileno(f), fileno(f));
:
: system(cmd);
: free(cmd);
: if (f != stderr) fclose(f);
: }
Stack back traces are easy on x86, but get a lot harder on !x86 at
high optimization layers without help from libunwind. That's the down
side of not relying on gdb... :)
Warner
next prev parent reply other threads:[~2010-10-02 21:39 UTC|newest]
Thread overview: 22+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-09-28 5:54 [TUHS] 2.11BSD cross compiler Nick Downing
2010-09-29 0:24 ` Tim Newsham
2010-09-29 0:51 ` Larry McVoy
2010-09-29 2:14 ` John Cowan
2010-09-29 2:38 ` Larry McVoy
2010-09-29 2:59 ` John Cowan
2010-09-29 3:44 ` Larry McVoy
2010-09-30 4:22 ` [TUHS] PDP-8 (was: 2.11BSD cross compiler) Greg 'groggy' Lehey
2010-09-30 4:53 ` John Cowan
2010-09-30 13:50 ` Larry McVoy
2010-10-02 3:46 ` Greg 'groggy' Lehey
2010-10-02 21:03 ` Larry McVoy
2010-10-02 21:39 ` M. Warner Losh [this message]
2010-10-02 10:06 ` Wolfgang Helbig
2010-09-29 3:14 ` [TUHS] 2.11BSD cross compiler M. Warner Losh
2010-09-29 3:17 ` Steve Nickolas
2010-09-29 3:55 ` Larry McVoy
2010-09-29 4:34 ` [TUHS] 6502 and swtch, was " Warren Toomey
2010-09-29 5:13 ` Steve Nickolas
2010-09-30 17:49 ` Tim Newsham
2010-09-29 20:54 ` [TUHS] " Peter Jeremy
2010-09-29 21:34 ` Larry McVoy
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