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To: Andrew Cagney <ac131313@redhat.com>
Cc: gdb-patches@sources.redhat.com,
	Kris Warkentin <kewarken@qnx.com>,
	Daniel Jacobowitz <drow@mvista.com>
Subject: Re: RFA: osabi: correct test for compatible handlers
References: <vt2n0buw7r5.fsf@zenia.home> <3F96D128.5040904@redhat.com>
From: Jim Blandy <jimb@redhat.com>
Date: Wed, 22 Oct 2003 20:04:00 -0000
In-Reply-To: <3F96D128.5040904@redhat.com>
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Andrew Cagney <ac131313@redhat.com> writes:

> > +   /* BFD's 'A->compatible (A, B)' functions return zero if A and B are
> > +      incompatible.  But if they are compatible, it returns the 'more
> > +      featureful' of the two arches.  That is, if A can run code
> > +      written for B, but B can't run code written for A, then it'll
> > +      return A.
> > + +      struct bfd_arch_info objects are atoms: that is, there's
> > supposed
> > +      to be exactly one instance for a given machine.  So you can tell
> > +      whether two are equivalent by comparing pointers.  */
> > +   return (a == b || a->compatible (a, b) == a);
> 
> Hey, nice.
> 
> Don't worry about a can_run_code_for function though, having the logic
> inline makes what's happening easier to understand (and will simplify
> a follow-on wild-card patch I've got pending).

It may be easier for you, but the original author did get the test
backwards, and I had to go through an embarrassing number of wrong
tries before I got it right.  I'd really like to leave the function
separate.