c/4794: gcc hangs on small, simple code fragment

[fritz at intrinsity dot com]

>Number:         4794
>Category:       c
>Synopsis:       gcc hangs on small, simple code fragment
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Mon Nov 05 12:46:00 PST 2001
>Closed-Date:
>Last-Modified:
>Originator:     Fritz Boehm
>Release:        gcc version 2.96 20000731 (Red Hat Linux 7.1 2.96-94.Intrinsity)
>Organization:
>Environment:
Red Hat Linux 7.1 running on a K7 1 GHz with 256MB RAM
>Description:
gcc hangs on a simple code fragment.
>How-To-Repeat:
gcc -c bug3.cc
>Fix:
If the boolean in the if clause is explicitly put in a
variable, and this variable is used in the if clause, then
gcc very quickly compiles the code.  Also, if a number of
variables in the if clause are eliminated, the compiler
will finish.  I deleted 11 of the variables and the compile
time went down to 15 seconds or so.
>Release-Note:
>Audit-Trail:
>Unformatted:
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