Re: semi-random crashes on some macppc hardware

I have for quite some time experienced similar crashes but it was always
in C/C++ compiler when building packages, particularly those with a long
list of dependencies to work through.  The system in question is a G4
PowerMac (AGP Graphics), commonly referred to, IIUC, as "Sawtooth".  It
boots and runs from local disk.

Using GCC 4.8.5 and prior, one would be working through dependencies
until GCC would fail with "internal compiler error: Segmentation fault".
If one simply restarted the build, it would likely complete the file it
was working on previously, but then segfault while processing the next
source file or perhaps one following.  The only workaround I ever found
was to reboot the machine and pick up where I left off.  Then it would
either complete the list of dependencies and possibly the target package,
or at least run for a reasonably long time before having to repeat the
process.

With the switch to GCC 5.3.0, the problem occurs more frequently, but
the reboot workaround seems not especially helpful or necessary.  For
some reason, I conciously chose not to reboot the machine after the
compiler segfaulted, but did do "make clean clean-depends" before
restarting the package build.  It would certainly get much farther
along between incidents (not just the next source file as before), but
still more frequent than a freshly-rebooted machine running GCC 4.x
would.

I applied the patch posted previously and while it does not eliminate
the problem, it seems to have reduced the frequency to at least the
prior level.  I have not rebooted the machine following the segfaults,
but continue to run "make clean clean-depends" before restarting a
package build.

I've been hesitant to consider hardware problems as back when it last
had MacOS X (10.4.11) installed, it worked just fine.  Perhaps I should
stick another disk in it and verify that it still does.


The other viable system is a Titanium PowerBook G4 (667MHz) which runs
NetBSD strictly via NFS (MacOS X 10.4.11 on internal disk).  It has
never exhibited the compiler segfault problem except when trying to
perform the final link step of "firefox".  I have not yet tried it
with a GCC 5.3.0-built system or the native GCC 5.3.0.

-- 
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