optimization/9037: [tree-ssa] -fssa-dce crashes with simple code

[renau@cs.uiuc.edu]

>Number:         9037
>Category:       optimization
>Synopsis:       [tree-ssa] -fssa-dce crashes with simple code
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Sun Dec 22 09:56:00 PST 2002
>Closed-Date:
>Last-Modified:
>Originator:     renau@cs.uiuc.edu
>Release:        GNU C version 3.5-tree-ssa 20021217 (experimental) (i686-pc-linux-gnu)
>Organization:
>Environment:

>Description:
This is a bug in the tree-ssa branch (experimental). When I activate the -fssa -fssa-dce with -O1 (it does not happen without optimization -O0) gcc crashes.

 The output:

 ./cc1 -fpreprocessed pp.i -quiet -dumpbase pp.c -auxbase pp -O1 -version -fssa -fssa-dce -o pp.s
GNU C version 3.5-tree-ssa 20021217 (experimental) (i686-pc-linux-gnu)
        compiled by GNU C version 3.2 (Mandrake Linux 9.0 3.2-1mdk).
/home/renau/tmp/pp.c: In function `vadd':
/home/renau/tmp/pp.c:8: internal compiler error: RTL flag check: INSN_DEAD_CODE_P used with unexpected rtx code `note' in mark_all_insn_unnecessary, at ssa-dce.c:452
Please submit a full bug report,
with preprocessed source if appropriate.
See <URL:http://www.gnu.org/software/gcc/bugs.html> for instructions.
ne
>How-To-Repeat:
./xgcc -v -save-temps -O1 -B. -fssa -fssa-dce -S ~/tmp/pp.c
>Fix:

>Release-Note:
>Audit-Trail:
>Unformatted:
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