[tlbuild] Building TL 2015

[Karl Berry]

I realize all this was irrelevant to the actual gmp problem, but anyway ...

     ./Build --build=i686-apple-darwin9 CC='gcc -m32' CXX='g++ -m32' \
             OBJCXX='g++ -m32'

    I couldnâ€™t get the system to even accept this command. It
    claimed not to understand -m32

I assume the error message was like:
configure: error: unrecognized option: `-m32'
(That's what I get when I try the given command.)

The problem is shell quoting.  The -m32 of course isn't intended to be
an option to configure, but to stick with the gcc.  I won't bore you
with the details (suffice it to say that the shell's eval is called).

There are various ways to deal with it, but I think perhaps the most
comprehensible is this:
  TL_BUILD_ENV="CFLAGS='-m32 -g -O2' CXXFLAGS='-m32 -O2 -g'" ./Build

(Of course adjusting the -g and/or -O2 to taste.)  I wish the
circumlotions were not necessary, but that's the way it is.

I'll tweak the tlbuild document.

Thanks,
Karl