Re: ANN: GCC 6.1.0 for OS X El Capitan

[Simon Wright <simon@pushface.org>]

It turns out that the native-2015 README makes a claim that I in fact
failed to fulfil. I've updated it and uploaded a patch for manual
application, if needed; only if you're going to be building a
relocatable library (e.g. your own version of GNATColl).

The relevant section of the updated README says

Library names
.............

The ld error "library not found for -lgnat-6.1" will be encountered
when using gprbuild to link a relocatable library (ordinary
relocatable links should be OK). The reason is that the GCC build
process only generates libgnat-6.dylib, libgnarl-6.dylib, but gprbuild
tries to link against libgnat-6.1.dylib (why it wouldn't just link
against libgnat.dylib I don't know).

You can fix by either of

* installing the necessary symbolic links: in
  $prefix/lib/gcc/x86-64-apple-darwin15/6.1.0/adalib,
   sudo ln -s libgnat-6.dylib libgnat-6.1.dylib
   sudo ln -s libgnarl-6.dylib libgnarl-6.1.dylib

* patch gprbuild's database: download
  share-gprconfig-compilers.xml.diff, then in $prefix,
   sudo patch -p1 <~/Downloads/share-gprconfig-compilers.xml.diff