Re: [RFA] patch to add 'maint profile-gdb' command

[Eli Zaretskii <eliz at is dot elta dot co dot il>]

On Mon, 10 Sep 2001, Jason Molenda wrote:

> This is a refresh of Tom Tromey's gdb profiling patch, originally here:
> 	http://sources.redhat.com/ml/gdb-patches/2000-q1/msg00022.html

Thanks!  I think it's a very useful feature, but I have a few minor 
comments.

> My only comments on this patch are (1) the documentation entry
> could note that your gmon.out file will be overwritten each time
> gdb is started, even if you don't do a profile-gdb on command[1], and
> (2) the configure.in check for $enable_profiling could be embedded
> in the AC_ARG_ENABLE() autoconf call.  It doesn't make any practical
> difference, but it looks like tradition in gdb's configure.in is
> to include this code inside the AC_ARG_ENABLE call.
> 
>  [1]  A bit of profiling happens before it can be turned
>       off in captured_main().  This initial profiling will overwrite
>       away any existing gmon.out.  At least it does with the gprof
>       on Linux and FreeBSD systems.

Isn't it better to use monstartup instead of moncontrol and -pg?  It 
looks like using monstartup could solve several problems:

  - you don't overwrite gmon.out unless you actually profile
  - you can link without -pg
  - you can make this option available by default, since it is invisible 
    unless you actually profile (I dislike features that require a 
    rebuild to become available)

We will have to add Autoconf tests to see if monstartup is available, but 
I think using moncontrol if --enable-profiling is given is not safe 
enough anyway.

In addition, I think the commands this patch adds should be documented in 
gdb.texinfo as well, since all commands one can type at GDB's prompt 
should be described there.