Tree sharing issues...

[Jan Hubicka <jh at suse dot cz>]

> > On Wed, Nov 19, 2003 at 08:01:52PM +0100, Jan Hubicka wrote:
> > > I am almost done with verify_stmts except for tree sharing, as I am
> > > still not clear about the tree sharing rules.  (Did I mentioned it in
> > > original email?)
> > 
> > Yes.  I don't know anything about tree sharing rules.  I expect we
> > can't share much.
> 
> I think we do pretty heavy shaing via CCP that does move around the
> constant PLUS_EXPRs and friends.  I am not even aware of way to copy
> tree expressions.
> I wrote the code for testing and will run it once my other bootstrap
> finish and come back with results.
OK, first possitive in bootstrap is not very far:
stage1/xgcc -Bstage1/ -B/usr/local/i686-pc-linux-gnu/bin/ -c   -g -O2
-DIN_GCC   -W -Wall -Wwrite-strings -Wstrict-prototypes
-Wmissing-prototypes -pedantic -Wno-long-long -Wold-style-definition
-Werror -fno-common   -DHAVE_CONFIG_H -DGENERATOR_FILE    -I. -I.
-I../../gcc -I../../gcc/.
-I../../gcc/../include   ../../gcc/gengtype.c -o gengtype.o
(const char *)"*x";

../../gcc/gengtype.c: In function `write_local_func_for_structure':

../../gcc/gengtype.c:2184: error: Wrong sharing of tree nodes
../../gcc/gengtype.c:2184: internal compiler error: verify_stmts failed.


A shared NOP.  Is this valid? If not, how to duplicate the nodes in CCP?

Honza