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incorrect optimization of 0.0 * Infinity



>Submitter-Id:	net
>Originator: Peter Ross	
>Organization:	
>Confidential:	no
>Synopsis:	incorrect optimization of 0.0 * Infinity
>Severity:	serious
>Priority:	medium
>Category:	optimization
>Class:		sw-bug
>Release:	3.0.4 (Debian testing/unstable)
>Environment:
System: Linux ceres 2.4.16 #1 Thu Dec 20 12:41:36 EST 2001 i686 Intel(R) Pentium(R) 4 CPU 1.60GHz GenuineIntel GNU/Linux
Architecture: i686

	
host: i386-pc-linux-gnu
build: i386-pc-linux-gnu
target: i386-pc-linux-gnu
configured with: ../src/configure -v --enable-languages=c,c++,java,f77,proto,objc --prefix=/usr --infodir=/share/info --mandir=/share/man --enable-shared --with-gnu-as --with-gnu-ld --with-system-zlib --enable-long-long --enable-nls --without-included-gettext --disable-checking --enable-threads=posix --enable-java-gc=boehm --with-cpp-install-dir=bin --enable-objc-gc i386-linux
>Description:
    0.0 * (DBL_MAX + DBL_MAX) is incorrectly optimized so that the
    result is 0.0 instead of Not a Number (NaN) at optimization level
    -O1 or greater.
>How-To-Repeat:
    gcc -O1 float.i
    ./a.out

0 is output and NaN should be.

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?3X^/3A>SQ<')T7PQ.SS&+Q;3$SK?_@<A&;$I5EP`````
`
end
>Fix:
    Compile with -O0.



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