various updates to build native GCC 12.

- for usr.bin, build libcody and link it into cc1*plus
- move makefile code for auto-build.h and version.h (was gcov-iov.h)
into makefile fragment to share them. (XXX probably best to only do
this in one place, but that's a future step.)
- many updates to handle the .c -> .cc renames
- build some x86 files with -msse2
- bump shlib versions for libgomp and libstdc++v3
- fix MKGCCCMDS=no builds
- updates for new rtl-ssa subdir
- use -std=gnu++11 for various places
- define TARGET_MACHINE and HOST_MACHINE for some places
- avoid a .BEGIN rule that writes to missing obj (ie src) sometimes

cleanups still needed:
- remove a bunch of commented -Wno* that don't seem to be needed anymore
- leave or remove various vax-specific -O0s that should no longer be
necessary for the vax-gcc port
- some "XXXGCC12" that should be may be fixable or converted to using our
standard ${CC_...} warnings (but may need to remain, in which case the
XXXGCC12 marker will be removed.)

with these, and a few other changes around the tree, i've able to build
gcc12 releases for several ports that seem to work (arm64, sparc, amd64,
i386 at least so far, have run, several others have built.)

update for GCC 5.3

port over 3 changes made here in the GCC 4.5 tree that we'll need
when GCC 4.8 becomes "gcc.old" eventually.

this tree still needs to be tested for more, but this should be the
bulk of the work.

----
Log Message:
prepare for moving GCC 4.5 into gcc.old:

- convert to using ${EXTERNAL_GCC_SUBDIR}
- define base-external-gpl3-gcc* subdir as GCC_SUBDIR
- use <bsd.init.mk> over <bsd.own.mk> for a bunch of places; mostly
because it arranges for ../Makefile.inc to be included earlier, and
don't bother including the latter if the former is already included.
- move all .PATH: settings after <bsd.{own,lib}.mk> so that all
valid variables are set before it is evaluated
- rename mknative-gcc* to match their subdir name.

XXX the relationship between the Makefile.inc/Makefile.gcc_path files
is kind of sketchy, it would be great if this was fixed.

----
Log Message:
oops, avoid re-setting DIST to something that might be wrong now.

----
Log Message:
fix another dated DIST.

branches: 1.7.2;
merge GCC 4.8 build.

prepare for moving GCC 4.5 into gcc.old:

- convert to using ${EXTERNAL_GCC_SUBDIR}
- define base-external-gpl3-gcc* subdir as GCC_SUBDIR
- use <bsd.init.mk> over <bsd.own.mk> for a bunch of places; mostly
because it arranges for ../Makefile.inc to be included earlier, and
don't bother including the latter if the former is already included.
- move all .PATH: settings after <bsd.{own,lib}.mk> so that all
valid variables are set before it is evaluated
- rename mknative-gcc* to match their subdir name.

XXX the relationship between the Makefile.inc/Makefile.gcc_path files
is kind of sketchy, it would be great if this was fixed.

Add MACHINE_ARCH's evbearmv5-e[bl] to work
Don't build _muldi3 _negdi2 _lshrdi3 _ashldi3 _ashrdi3 on earm and coldfire

Remove a hack.

XXX: Use earm for earmeb

branches: 1.2.2; 1.2.8;
clean out some unused code.

*sigh* move these files into the directories i meant for them to exist in.
start actually porting to gcc 4.5 in the process.

update for GCC 5.3

port over 3 changes made here in the GCC 4.5 tree that we'll need
when GCC 4.8 becomes "gcc.old" eventually.

this tree still needs to be tested for more, but this should be the
bulk of the work.

----
Log Message:
prepare for moving GCC 4.5 into gcc.old:

- convert to using ${EXTERNAL_GCC_SUBDIR}
- define base-external-gpl3-gcc* subdir as GCC_SUBDIR
- use <bsd.init.mk> over <bsd.own.mk> for a bunch of places; mostly
because it arranges for ../Makefile.inc to be included earlier, and
don't bother including the latter if the former is already included.
- move all .PATH: settings after <bsd.{own,lib}.mk> so that all
valid variables are set before it is evaluated
- rename mknative-gcc* to match their subdir name.

XXX the relationship between the Makefile.inc/Makefile.gcc_path files
is kind of sketchy, it would be great if this was fixed.

----
Log Message:
oops, avoid re-setting DIST to something that might be wrong now.

----
Log Message:
fix another dated DIST.

branches: 1.7.2;
merge GCC 4.8 build.

prepare for moving GCC 4.5 into gcc.old:

- convert to using ${EXTERNAL_GCC_SUBDIR}
- define base-external-gpl3-gcc* subdir as GCC_SUBDIR
- use <bsd.init.mk> over <bsd.own.mk> for a bunch of places; mostly
because it arranges for ../Makefile.inc to be included earlier, and
don't bother including the latter if the former is already included.
- move all .PATH: settings after <bsd.{own,lib}.mk> so that all
valid variables are set before it is evaluated
- rename mknative-gcc* to match their subdir name.

XXX the relationship between the Makefile.inc/Makefile.gcc_path files
is kind of sketchy, it would be great if this was fixed.

Add MACHINE_ARCH's evbearmv5-e[bl] to work
Don't build _muldi3 _negdi2 _lshrdi3 _ashldi3 _ashrdi3 on earm and coldfire

Remove a hack.

XXX: Use earm for earmeb

branches: 1.2.2; 1.2.8;
clean out some unused code.

*sigh* move these files into the directories i meant for them to exist in.
start actually porting to gcc 4.5 in the process.

port over 3 changes made here in the GCC 4.5 tree that we'll need
when GCC 4.8 becomes "gcc.old" eventually.

this tree still needs to be tested for more, but this should be the
bulk of the work.

----
Log Message:
prepare for moving GCC 4.5 into gcc.old:

- convert to using ${EXTERNAL_GCC_SUBDIR}
- define base-external-gpl3-gcc* subdir as GCC_SUBDIR
- use <bsd.init.mk> over <bsd.own.mk> for a bunch of places; mostly
because it arranges for ../Makefile.inc to be included earlier, and
don't bother including the latter if the former is already included.
- move all .PATH: settings after <bsd.{own,lib}.mk> so that all
valid variables are set before it is evaluated
- rename mknative-gcc* to match their subdir name.

XXX the relationship between the Makefile.inc/Makefile.gcc_path files
is kind of sketchy, it would be great if this was fixed.

----
Log Message:
oops, avoid re-setting DIST to something that might be wrong now.

----
Log Message:
fix another dated DIST.

branches: 1.7.2;
merge GCC 4.8 build.

prepare for moving GCC 4.5 into gcc.old:

- convert to using ${EXTERNAL_GCC_SUBDIR}
- define base-external-gpl3-gcc* subdir as GCC_SUBDIR
- use <bsd.init.mk> over <bsd.own.mk> for a bunch of places; mostly
because it arranges for ../Makefile.inc to be included earlier, and
don't bother including the latter if the former is already included.
- move all .PATH: settings after <bsd.{own,lib}.mk> so that all
valid variables are set before it is evaluated
- rename mknative-gcc* to match their subdir name.

XXX the relationship between the Makefile.inc/Makefile.gcc_path files
is kind of sketchy, it would be great if this was fixed.

Add MACHINE_ARCH's evbearmv5-e[bl] to work
Don't build _muldi3 _negdi2 _lshrdi3 _ashldi3 _ashrdi3 on earm and coldfire

Remove a hack.

XXX: Use earm for earmeb

branches: 1.2.2; 1.2.8;
clean out some unused code.

*sigh* move these files into the directories i meant for them to exist in.
start actually porting to gcc 4.5 in the process.

Rebase to HEAD as of a few days ago.

resync from head

resync with head

sync with head.

for a reference, the tree before this commit was tagged
as yamt-pagecache-tag8.

this commit was splitted into small chunks to avoid
a limitation of cvs. ("Protocol error: too many arguments")

sync with (a bit old) head

Rebase.