Re: 3.1 Bootstrap failure on sparc-solaris2.8

[Roman Lechtchinsky <rl at cs dot tu-berlin dot de>]

> > > The error is
> > > 
> > > __GCC_FLOAT_NOT_NEEDED  -I. -I. -I../../gcc -I../../gcc/. -I../../gcc/config -I../../gcc/../include  -DL_floatdisf -c ../../gcc/libgcc2.c -o libgcc/./_floatdisf.o
> > > ../../gcc/libgcc2.c: In function `__floatdisf':
> > > ../../gcc/libgcc2.c:1129: Internal compiler error in subreg_highpart_offset, at emit-rtl.c:1180
> > 
> > See http://gcc.gnu.org/ml/gcc-patches/2001-06/msg01619.html which fixes
> > this and still hasn't been reviewed (just a shameless plug :-).
> 
> This patch no longer applies cleanly to the 3.1 tree; perhaps you
> can update it and resubmit it.  My understanding is that patches
> that fix bootstrap failures are given higher priority recently.

I have updated the patch but unfortunately I can't test it because make
bootstrap now aborts with

./xgcc -B./ -B/usr/local/sparc-sun-solaris2.7/bin/ -isystem
/usr/local/sparc-sun-solaris2.7/include -O2   -DIN_GCC    -W -Wall
-Wwrite-strings -Wstrict-prototypes -Wmissing-prototypes -isystem
./include  -fPIC -g1 -DHAVE_GTHR_DEFAULT -DIN_LIBGCC2
-D__GCC_FLOAT_NOT_NEEDED  -I. -I. -I../../../cvs/gcc/gcc
-I../../../cvs/gcc/gcc/. -I../../../cvs/gcc/gcc/config
-I../../../cvs/gcc/gcc/../include  -DL_clear_cache -c
../../../cvs/gcc/gcc/libgcc2.c -o libgcc/./_clear_cache.o
cc1: warning: changing search order for system directory "include"
cc1: warning:   as it has already been specified as a system directory
../../../cvs/gcc/gcc/libgcc2.c: In function `__clear_cache':
../../../cvs/gcc/gcc/libgcc2.c:2467: Virtual array basic_block_info[1]:
element 1 out of bounds
../../../cvs/gcc/gcc/libgcc2.c:2467: confused by earlier errors, bailing
out

The problem is caused by this line in try_optimize_cfg:

	      c = BASIC_BLOCK (i ? i - 1 : i + 1);

This doesn't work because there is only one basic block so i+1 is out of
bounds. I'll try to understand what's going on here if I have the time
which is not too probable :-(

Bye

Roman