Re: x86-64 gdbserver config

[Joel Brobecker <brobecker@adacore.com>]

Hello Nathan,

> This patch allows building an x86-64 gdbserver for a multilibbed  
> i686-pc-linux-gnu target.  One cannot tell from the target triplet that 
> x86-64 source files are needed -- one must invoke the compiler and 
> examine the __x86_64__ #define.  For instance, the CC_FOR_TARGET may be 
> 'my-gcc -m64'.

I am trying to understand the situation under which this patch would
be used. Is it when using a cross compiler or can it be when using
a native compiler? Or both?

I'm a little confused, because I was under the impression that the target
was either specified using configure --target=, or deduced using
"config.guess".  Either way, I would have thought that the user is
responsible for configuring gdbserver as needed.

This is something that we do already when building GDB for sparc64.
However, I just noticed today that on pc/solaris, config.guess actually
returns different values dependending on whether our GCC was configured
as i386-sun-solaris2.8 or x86_64-sun-solaris2.8... I don't think the
same sort of trick is really applicable to GNU/Linux, though.

Anyway, just trying to think aloud for now...

-- 
Joel