Profile-directed feedback and remote testing

[Joe Buck]

On Fri, Mar 25, 2005 at 08:03:55PM +0100, Gabriel Dos Reis wrote:
> Joe Buck <Joe.Buck@synopsys.COM> writes:
> | That wouldn't have saved me in the case described above, as the pathnames
> | are already set in the executable.  A *runtime* way of altering the
> | locations of the .gcda files would be nice to have.  For example, we could
> | have something like
> 
> I guess I was unclear:  What I meant was a compiler option, meaning it
> is specified when the compiler is run to compiler something, like
> 
>     gcc --profile-output-dir=/blah/blah

No, you were clear.  As I said, the problem with your suggested approach
is that, once the executable is compiled, the paths for the profile data
are still wired in.  All you've done is change the paths.

What I'd like is the ability to alter the paths at runtime, without
recompiling.  This would have all kinds of uses, like maintaining
separate counts files for two classes of runs, allowing people to
generate profiling data for the same executable without stepping on
each others' work, etc.