"division: function singularity" in libjava/java/lang/e_log.c:107

[Andrew Haley]

Tom Tromey writes:
 > >>>>> "Christian" == Christian Joensson <c.christian.joensson@telia.com> writes:
 > 
 > Christian> When looking through the testresults in 
 > Christian> http://gcc.gnu.org/ml/gcc-testresults/2002-02/msg00363.html
 > Christian> I see a strange warning "division: function singularity".
 > 
 > I never saw a reply to this.
 > 
 > Christian> ../../../libjava/java/lang/e_log.c: In function `__ieee754_log':
 > Christian> ../../../libjava/java/lang/e_log.c:107: warning: division: function singularity
 > Christian> Is this a serious warning?

It's this line:

	    if (hx<0) return (x-x)/zero;	/* log(-#) = NaN */
	
In other words, the code is deliberately returning NaN for log of a
negative number.  The compiler is complaining about correct code.

Andrew.