[Bug bootstrap/14671] [3.3/3.4 regression] caller-save.c:491: internal compiler error: Segmentation fault

["dave at hiauly1 dot hia dot nrc dot ca" <gcc-bugzilla at gcc dot gnu dot org>]

------- Additional Comments From dave at hiauly1 dot hia dot nrc dot ca  2004-05-27 03:38 -------
Subject: Re:  [3.3/3.4 regression] caller-save.c:491: int

> The new regression caused by Dave backporting rth's patch on 04/24 is 
> unrelated and was detected by me only because I did a full regression 
> run on the POOMA tests with the (appearantly) fixed compiler.

This assertion has not been proved.  I've seen a number of bugs recently
that were totally unrelated to the change that introduced them.

If you look at the comment in ggc-page.c for lookup_page_table_entry,
you will see that it says "Die (probably) if the object wasn't allocated
via GC."  The patch in question didn't create the object that caused
the ICE.  Thus, as I indicated previously, more information is needed
about the object that caused the ICE, and how and when it was added
to the alias_invariant array.

The alias_invariant array is supposed to contain RTX objects and these
are always allocated via GC as far as I know.  So, marking the objects
in this array shouldn't be a problem unless some are not GC objects.

Richard has indicated that the regression isn't present on 3.4, yet it
has essentially the same change.  If we revert this on 3.5, the pa and
alpha won't build.  The build problems are critical for these ports.

Dave


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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14671