[M3devel] gcc 4.5

[Jay K]

I'm inclined to make gcc 4.5 the default backend very soon.
AMD64_DARWIN, I386_LINUX, SOLgnu are looking ok.
  I could also test PPC, like PPC_LINUX.

SOLgnu leaves everything volatile (same as 4.3) so maybe isn't much validation.

I doubt there is much value in testing other operating systems, mainly just other processors.
   Though there is sometimes, e.g. I think I386_DARWIN uses sse for floating point and other I386 systems don't.
   I should also test SPARC_LINUX to get sparc w/o volatile.


There are many other targets. OpenBSD, NetBSD, FreeBSD, OSF/1, I386/AMD64_SOLARIS, ARMEL_LINUX, Cygwin, MinGW, etc.
Others can test them?


There is some downside, in particular I disable more optimization at -O3 than with gcc 4.3.
One of the additional optimizations perhaps doesn't exist in 4.3 though.


The label/barrier thing still isn't resolved.
I haven't run through m3-sys/m3tests.


But that the system can build itself is a good sign, though sometimes I overvalue it.
And I tested some gui apps at least unoptimized.
The "man vs. boy" test works.


The 4.3 backend will remain available via cm3 -DGCC43 in the m3cc directory.
  You have to be careful about cm3cfg.common probing around and finding the intended one,
  such as by deleting all others.


 - Jay