Hello, This patch documents https://sourceware.org/bugzilla/show_bug.cgi?id=13932 as requested in https://sourceware.org/bugzilla/show_bug.cgi?id=15267. It would be nice to add more details, but it seems the behavior and its consequences is not well understood. The purpose of the note is to warn users of this behavior and thus avoid frustration (http://entropymine.com/imageworsener/slowpow/). This is my first patch. I followed (hopefully correctly) the instructions here: https://www.kernel.org/doc/man-pages/patches.html Cheers, Manuel.
diff --git a/man3/pow.3 b/man3/pow.3 index d0a2ea8..3d2151a 100644 --- a/man3/pow.3 +++ b/man3/pow.3 @@ -320,6 +320,17 @@ The variant returning also conforms to SVr4, 4.3BSD, C89. .SH BUGS +On 64-bits, +.\" +.\" https://sourceware.org/bugzilla/show_bug.cgi?id=13932 +.BR pow () +may be more than 10,000 times slower for some inputs than for other nearby +inputs. The inputs that produce such behavior are different for +.BR powf (), +.BR pow () +and +.BR powl (). + In glibc 2.9 and earlier, .\" .\" http://sources.redhat.com/bugzilla/show_bug.cgi?id=6776
