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Re: Writing "absolutely" portable code

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On 01/11/2012 06:10 AM, ec429 wrote:
,,,
> What, exactly, don't you like about gdb?  Does it not hold your hand 
> enough, poor ickle child?  Are there not enough pictures to engage your 
> attention?


The main things I don't like about gdb might actually be features of
gcc. The only thing I can say for certain is that the two tools don't
communicate with each other properly Even when I compile with
optimization turned (supposedly) completely off, I often face the
problems like the following:

* A variable, whose value I want to check, has been optimized out of
existence.

* I will advance though the program one step at a time. gdb will display
line 34, line 35, line 34, line 35, line 34, etc, which would be fine if
they were parts of loop, but is very disconcerting when one of those
lines is a comment and the other is a declaration. Eventually it stops
cycling between those line numbers, and jumps to line 39, and by
examination of the values of various variables, I conclude that what
it's actually been doing was executing the loop on lines 36 and 37.

* I will single-step through a line of code that supposedly changes the
value of a variable, examining the value of that variable before and
after execution of the statement, and see the value unchanged. It
eventually gets changed, but during what is supposed to be the execution
of some other line of code much farther down in the code.

I can't be sure whether these problems are the fault of gdb or gcc.
However, I only ran into similar problems using the IRIX MIPS-Pro
compiler and dbx if I chose optimization levels higher than the lowest
possible one. That is why I usually debug with all optimizations turned
off - unless turning optimization off makes the bug disappear.

I have other problems with gdb as well, but they're just due to lack of
experience with the program, I presume. I've been using dbx for more
than two decades, possibly three.

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Writing "absolutely" portable code ArifulHossain tuhin <etothepowerpi@gmail.com> - 2012-01-09 02:26 -0800
  Re: Writing "absolutely" portable code ec429 <ec429@cam.ac.uk> - 2012-01-09 11:47 +0000
    Re: Writing "absolutely" portable code Jens Gustedt <jens.gustedt@loria.fr> - 2012-01-09 13:56 +0100
    Re: Writing "absolutely" portable code ArifulHossain tuhin <etothepowerpi@gmail.com> - 2012-01-09 05:45 -0800
      Re: Writing "absolutely" portable code ec429 <ec429@cam.ac.uk> - 2012-01-09 14:46 +0000
        Re: Writing "absolutely" portable code ArifulHossain tuhin <etothepowerpi@gmail.com> - 2012-01-10 01:11 -0800
    Re: Writing "absolutely" portable code Rui Maciel <rui.maciel@gmail.com> - 2012-01-09 15:58 +0000
    Re: Writing "absolutely" portable code falk@rahul.net (Edward A. Falk) - 2012-01-09 18:41 +0000
  Re: Writing "absolutely" portable code Rui Maciel <rui.maciel@gmail.com> - 2012-01-09 12:23 +0000
    Re: Writing "absolutely" portable code Eric Sosman <esosman@ieee-dot-org.invalid> - 2012-01-09 08:45 -0500
      Re: Writing "absolutely" portable code superpollo <superpollo@tznvy.pbz> - 2012-01-09 15:02 +0100
        Re: Writing "absolutely" portable code Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-01-09 16:11 +0000
    Re: Writing "absolutely" portable code ArifulHossain tuhin <etothepowerpi@gmail.com> - 2012-01-09 05:56 -0800
      Re: Writing "absolutely" portable code Rui Maciel <rui.maciel@gmail.com> - 2012-01-09 15:07 +0000
        Re: Writing "absolutely" portable code ArifulHossain tuhin <etothepowerpi@gmail.com> - 2012-01-10 01:21 -0800
          Re: Writing "absolutely" portable code Stephen Sprunk <stephen@sprunk.org> - 2012-01-10 13:20 -0600
            Re: Writing "absolutely" portable code ArifulHossain tuhin <etothepowerpi@gmail.com> - 2012-01-11 06:57 -0800
          Re: Writing "absolutely" portable code Rui Maciel <rui.maciel@gmail.com> - 2012-01-11 09:23 +0000
  Re: Writing "absolutely" portable code jacob navia <jacob@spamsink.net> - 2012-01-09 13:48 +0100
    Re: Writing "absolutely" portable code ec429 <ec429@cam.ac.uk> - 2012-01-09 13:11 +0000
      Re: Writing "absolutely" portable code Nick Keighley <nick_keighley_nospam@hotmail.com> - 2012-01-09 05:27 -0800
        Re: Writing "absolutely" portable code ec429 <ec429@cam.ac.uk> - 2012-01-09 13:41 +0000
          Re: Writing "absolutely" portable code ArifulHossain tuhin <etothepowerpi@gmail.com> - 2012-01-09 06:09 -0800
      Re: Writing "absolutely" portable code jacob navia <jacob@spamsink.net> - 2012-01-09 14:35 +0100
        Re: Writing "absolutely" portable code Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-01-09 13:44 +0000
          Re: Writing "absolutely" portable code ArifulHossain tuhin <etothepowerpi@gmail.com> - 2012-01-09 06:18 -0800
          Re: Writing "absolutely" portable code jacob navia <jacob@spamsink.net> - 2012-01-09 18:59 +0100
          Re: Writing "absolutely" portable code jacob navia <jacob@spamsink.net> - 2012-01-09 19:01 +0100
            Re: Writing "absolutely" portable code ec429 <ec429@cam.ac.uk> - 2012-01-09 19:21 +0000
              Re: Writing "absolutely" portable code Richard <rgrdev_@gmail.com> - 2012-01-10 20:48 +0100
                Re: Writing "absolutely" portable code David Dyer-Bennet <dd-b@dd-b.net> - 2012-01-10 14:26 -0600
                Re: Writing "absolutely" portable code Richard <rgrdev_@gmail.com> - 2012-01-10 21:44 +0100
                Re: Writing "absolutely" portable code David Dyer-Bennet <dd-b@dd-b.net> - 2012-01-10 15:45 -0600
                Re: Writing "absolutely" portable code Rui Maciel <rui.maciel@gmail.com> - 2012-01-11 09:12 +0000
                Re: Writing "absolutely" portable code ec429 <ec429@cam.ac.uk> - 2012-01-11 11:10 +0000
                Re: Writing "absolutely" portable code James Kuyper <jameskuyper@verizon.net> - 2012-01-11 11:52 -0500
                Re: Writing "absolutely" portable code ec429 <ec429@cam.ac.uk> - 2012-01-11 17:01 +0000
                Re: Writing "absolutely" portable code James Kuyper <jameskuyper@verizon.net> - 2012-01-11 12:11 -0500
              Re: Writing "absolutely" portable code Rui Maciel <rui.maciel@gmail.com> - 2012-01-11 09:08 +0000
            Re: Writing "absolutely" portable code Rui Maciel <rui.maciel@gmail.com> - 2012-01-11 08:22 +0000
            Re: Writing "absolutely" portable code Rui Maciel <rui.maciel@gmail.com> - 2012-01-11 08:54 +0000
        Re: Writing "absolutely" portable code ec429 <ec429@cam.ac.uk> - 2012-01-09 13:57 +0000
          Re: Writing "absolutely" portable code Seebs <usenet-nospam@seebs.net> - 2012-01-09 19:21 +0000
            Re: Writing "absolutely" portable code ec429 <ec429@cam.ac.uk> - 2012-01-09 19:52 +0000
              Re: Writing "absolutely" portable code Seebs <usenet-nospam@seebs.net> - 2012-01-09 20:20 +0000
        Re: Writing "absolutely" portable code ArifulHossain tuhin <etothepowerpi@gmail.com> - 2012-01-09 06:16 -0800
    Re: Writing "absolutely" portable code ArifulHossain tuhin <etothepowerpi@gmail.com> - 2012-01-09 06:02 -0800
  Re: Writing "absolutely" portable code Keith Thompson <kst-u@mib.org> - 2012-01-09 14:50 -0800
    Re: Writing "absolutely" portable code Kaz Kylheku <kaz@kylheku.com> - 2012-01-09 23:20 +0000
      Re: Writing "absolutely" portable code Rui Maciel <rui.maciel@gmail.com> - 2012-01-10 00:23 +0000
    Re: Writing "absolutely" portable code Dirk Zabel <zabel@riccius-sohn.eu> - 2012-01-10 17:44 +0100
      Re: Writing "absolutely" portable code ArifulHossain tuhin <etothepowerpi@gmail.com> - 2012-01-11 07:13 -0800
      Re: Writing "absolutely" portable code Nick Bowler <nbowler@draconx.ca> - 2012-01-17 20:36 +0000
        Re: Writing "absolutely" portable code ec429 <ec429@cam.ac.uk> - 2012-01-17 23:06 +0000
          Re: Writing "absolutely" portable code blp@cs.stanford.edu (Ben Pfaff) - 2012-01-17 15:32 -0800
            Re: Writing "absolutely" portable code Kaz Kylheku <kaz@kylheku.com> - 2012-01-18 00:40 +0000
              Re: Writing "absolutely" portable code Seebs <usenet-nospam@seebs.net> - 2012-01-18 18:35 +0000
                Re: Writing "absolutely" portable code Kaz Kylheku <kaz@kylheku.com> - 2012-01-18 19:15 +0000
                Re: Writing "absolutely" portable code Seebs <usenet-nospam@seebs.net> - 2012-01-21 21:32 +0000
            Re: Writing "absolutely" portable code "io_x" <a@b.c.invalid> - 2012-01-18 07:26 +0100
              Re: Writing "absolutely" portable code "Joachim Schmitz" <nospam.jojo@schmitz-digital.de> - 2012-01-18 11:07 +0100
                Re: Writing "absolutely" portable code Seebs <usenet-nospam@seebs.net> - 2012-01-21 21:32 +0000
                Re: Writing "absolutely" portable code Ian Collins <ian-news@hotmail.com> - 2012-01-22 10:42 +1300
                Re: Writing "absolutely" portable code "io_x" <a@b.c.invalid> - 2012-01-22 18:53 +0100
                Re: Writing "absolutely" portable code "io_x" <a@b.c.invalid> - 2012-01-22 19:00 +0100
                Re: Writing "absolutely" portable code "io_x" <a@b.c.invalid> - 2012-01-23 19:28 +0100
              Re: Writing "absolutely" portable code Stephen Sprunk <stephen@sprunk.org> - 2012-01-18 08:44 -0600
              Re: Writing "absolutely" portable code James Dow Allen <jdallen2000@yahoo.com> - 2012-01-18 07:09 -0800
                Re: Writing "absolutely" portable code "io_x" <a@b.c.invalid> - 2012-01-18 17:44 +0100
        Re: Writing "absolutely" portable code Seebs <usenet-nospam@seebs.net> - 2012-01-18 07:58 +0000

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