RFR: JDK-8034788 Rewrite toolchain.m4 to support multiple toolchains per platform

[Magnus Ihse Bursie]

On 2014-02-13 13:20, Erik Joelsson wrote:
> I like these improvements but I can certainly see the need for more.
>
> Some minor things:
>
> flags.m4:
> 95: needs -> need
> 152: No need to "assume"
>
> toolchain.m4
> 171: detext
> ~230-300: Many rather long lines, consider breaking them up?
> 605: is -> are
> ~650: Why define MACOSX_VERSION_MIN in toolchain.m4 when it's used in 
> flags.m4?

As for the last question. I moved this to flags.m4, but I still don't 
think it belongs there, so the FIXME to move it elsewhere moved along 
with it. :-)

I have addressed the rest of your concerns as well, and those raised by 
Henry Jen. I solved the "list" issue by changing the 
--with-toolchain-type description to:

   --with-toolchain-type   the toolchain type (or family) to use, use 
'--help'
                           to show possible values [platform dependent]

And when your type "configure --help", at the end you will get:
The following toolchains are available as arguments to 
--with-toolchain-type.
Which are valid to use depends on the build platform.
   gcc         GNU Compiler Collection
   clang       clang/LLVM
   solstudio   Oracle Solaris Studio
   xlc         IBM XL C/C++
   microsoft   Microsoft Visual Studio

Unfortunately, we can't get the current platform at that point, so I'll 
have to list all. But I think that's okay. My main point was that you 
must be able to type "configure --help" and see what kind of options you 
can give. If you can't figure out that "microsoft" is invalid on linux, 
you'll be told soon enough by configure.

Updated webrev: 
http://cr.openjdk.java.net/~ihse/JDK-8034788-rewrite-toolchain-m4/webrev.02

/Magnus