optimization/5999: ICE for complex*16 divide with -ffast-math on ia64

[janis187@us.ibm.com]

>Number:         5999
>Category:       optimization
>Synopsis:       ICE for complex*16 divide with -ffast-math on ia64
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          ice-on-legal-code
>Submitter-Id:   net
>Arrival-Date:   Mon Mar 18 13:26:01 PST 2002
>Closed-Date:
>Last-Modified:
>Originator:     Janis Johnson
>Release:        gcc version 3.1 20020318 (prerelease)
>Organization:
>Environment:
Itanium; Red Hat Linux release 7.1.94 (Roswell)
>Description:
GCC 3.1 gets a segmentation violation compiling 301.apsi
and 168.wupwise from SPEC CPU2000 with "-O2 -ffast-math" on
ia64-unknown-linux-gnu.  In both cases this occurs for a
divide of a complex*16 variable when expand_expr passes a
NULL op0 to expand_binop, which in turn passes it to
protect_from_queue.

This is a regression from GCC 3.0.4, for which these two
benchmark programs build and run with no problems using
these options.
>How-To-Repeat:
Compile with attached test case with "g77 -O2 -ffast-math".
>Fix:
Unknown.
>Release-Note:
>Audit-Trail:
>Unformatted:
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