2008/6/28 Nick Roberts <nickrob@snap.net.nz>:

>  > I tried again with "gdb --annotate=3" (= without binary as parameter)
> and
>  > loaded the binary with
>  > (gdb) file binary.bin
>  > There was no "initialising..." message visible and I could start
>  > immediately. What's the difference ?
>
> Emacs just builds a list of filenames from GDB that were used to build the
> executable.  If you specify the name later in the GUD buffer, it doesn't
> build
> that list.  That makes it quicker but if there are relevant files in
> existing
> buffers or you visit them they won't be enabled for debugging, e.g., you
> won't
> be able to click in the fringe to set a breakpoint until execution has
> already
> stopped there.
>
How to disable emacs from "builds a list of filenames from GDB?"
I have the same problem, and You have given me similiar solution. But it
does not work.
So now, I prefer emacs not build it. Maybe there should be a flag for it.

>
>  > > There are several factors that might make this slow:
>  > >
>  > > 1) An executable that was created from a large number of files.
>  >
>  > gru@PT-AGCMLX1 >find . \( -name \*.cpp -o -name \*.h \) | wc -l
>  > 3072
>  >
>  > Would this qualify as "large" ? ;)
>
> A similar command for Emacs gives 375, so, ..err yes, that does sound
> rather
> large.
>
>  > > 2) Using stabs debug format.
>  >
>  > Hmm, not sure. I just compiled with gcc-2.95 (yes, that old....) and
> "-g".
>  > "info gcc" gives me the impression that this means stabs or gdb ...
>
> In GDB, once execution has started, e.g., after hitting a breakpoint, do
>
> (gdb) info source
> Current source file is myprog.c
> Compilation directory is /home/nickrob
> Located in /home/nickrob/myprog.c
> Contains 262 lines.
> Source language is c.
> Compiled with DWARF 2 debugging format.
>              ^^^^^^^
> Includes preprocessor macro info.
>
> Stabs is an old debug format and I suspect it might be the default for
> gcc-2.95.
> Maybe you can compile with DWARF 2 instead (using `-gdwarf-2') then Emacs
> should
> start up more qickly.
>
>  > > 3) Using an old PC.
>  >
>  > gru@CMDevLin2 >cat /proc/cpuinfo
>  > vendor_id       : GenuineIntel
>  > cpu family      : 15
>  > model           : 2
>  > model name      : Intel(R) Pentium(R) 4 CPU 2.40GHz
>  > cpu MHz         : 2405.535
>  > cache size      : 512 KB
>  >
>  > Not that old...
>  > CPU is at 20% while "initialising....".
>  > /home is mounted via nfs but I can hardly see any network activity while
>  > "initialising..."
>
> By old, I guess I mean 100MHz.  It looks like it might not be CPU bound,
> anyway.
>
>  > > If this is the problem I can post a patch that might speed things up
> but
>  > I would try this :)
>  >
>  > > just turning off gud-tooltip-mode might help.
>  >
>  > "gud-tooltip-mode is a variable defined in `gud.el'.
>  > Its value is nil"
>  >
>  > So it is turned off.
>  >
>  > Many thanks for your help :) For the time beeing, I'll just load the
>  > binary from within gdb. Everything seems to work and I don't have to
> wait
>  > 1:30 minutes. If my colleages see this, I will have to hear their
> laughter
>  > till the end of days ;)
>
> I think that has the same effect as my patch would, i.e., just not build
> the
> list.  It just means that initially you need to set breakpoints, etc, from
> the
> GUD buffer
>
> All these tasks that Emacs performs behind the users back should be
> benchmarked
> and optimised really, but I just haven't found the time.
>
> --
> Nick
> http://www.inet.net.nz/~nickrob <http://www.inet.net.nz/%7Enickrob>
>
>
>