Update GCC to autoconf 2.69, automake 1.15.1

[Janne Blomqvist]

On Wed, Oct 31, 2018 at 7:05 PM Joseph Myers <joseph@codesourcery.com>
wrote:

> I've committed this revised patch version


Thank you for taking on this work.


> As noted, my expectation is that libgfortran, libgo, libgomp,
> liboffloadmic, libsanitizer, libphobos maintainers will deal with
> moving those directories to subdir-objects, with any consequent fixes
> needed, to eliminate the automake warnings about subdirectory sources
> without using subdir-objects - and I don't know whether use of ../ in
> source paths in some directories complicates things (if subdir-objects
> would result in attempts to put resulting objects in ../, outside the
> normal build directory for the library) or not.
>

Turned out that for libgfortran, at least, this doesn't seem trivial.
Problem is that we have some of the sources listed relative to $(srcdir) in
Makefile.am, which breaks when enabling subdir-objects. But we can't remove
the $(srcdir) either, becase these sources in question are generated from
m4 sources when --enable-maintainer-mode is enabled, and $(srcdir) is thus
needed so that the generated files will correctly end up in in the source
tree and not the build tree. Gah!

I filed https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87856 to keep track of
this.

-- 
Janne Blomqvist