Re: Installation proposal

[Per Bothner <per@bothner.com>]

It does look like trying to directly copy the pre-install tree
into the real install tree is too fragile.  But I still think
having a 'build' directory that mirrors the structure of the
prefix directory makes sense, and we can get there incrementally.

My suggestion:

(1) configure creates a 'build' sub-directory at the top-level,
parallel to 'gcc', libstdc++', etc.  The Makefiles call this
directory $build_prefix.

(2) Let's start with (say) gcc.  Change the gcc makefile so that
all instances of 'xgcc' instead say '$build_prefix/bin/gcc'.
Does this for all of:
(a) The -o opten when actually linking the executable.
(b) In 'install-driver'
(c) In STAGESTUFF.
(d) In the libstdc++ and libjava directories if the refer to xgcc.

At this point we have (hopefully) a working consistent system.
If we haven't broken anything, we convert more files.
(3) The remianing drivers:  g++, gcj.
(4) Other binaries: fastjar/jar -> $build_prefix/bin/jar.
(5) The actual compilers:  cc1, cc1plus, jc1, ...
(6) Other generated files.
(7) At some point we have enough converted that we can remove
the -B flags in the run-time library directories.
(8) We change the testsuite so it just uses
'PATH=$build_prefix/bin:$PATH gcc ...' instead of build_prefix/bin/gcc.
-- 
	--Per Bothner
per@bothner.com   http://www.bothner.com/per/