tweaks for autoconf 2.50

[Geoff Keating]

"Zack Weinberg" <zackw@stanford.edu> writes:

> Autoconf 2.50 came out last week.  This patchset corrects several
> places where our configure scripts had ugly hacks that broke.  I do
> not introduce any new features; all the scripts still work with the
> old autoconf (I'm verifying this by running a bootstrap having
> regenerated them all with 2.13).
> 
> The tweaks fall into two major categories.  The specs have been
> tightened up, such that we have to be a more careful with quoting,
> recursive AC_REQUIRE, etc.  Also, the local copy of AC_PROG_CC in
> libiberty (propagated to libjava, libstdc++3, and several other
> places) had to die.  AC_PROG_CC from 2.13 works just fine when
> cross-compiling, we know this because the gcc directory has been using
> it all along.

I think you'll find that AC_PROG_CC from 2.13 doesn't work, because it
uses AC_PROG_CC_WORKS, which requires that the compiler be able to
link, and when you have no libc available because you had no compiler
to build it then obviously you can't link anything.

-- 
- Geoffrey Keating <geoffk@geoffk.org>