options(chmhelp = TRUE)

R> options(chmhelp = TRUE)
R> ?ls # use chm help
Warning message:
DLL attempted to change FPU control word from 8001f to 9001f

As Andy said, that's a bug in one of the help system DLLs.  There are
a number of Windows DLLs that contain this bug. 

I'm thinking of changing the behaviour in 1.7.0, as follows:

 1.  By default, the bug will be silently corrected.
 2.  Optionally, it will print the warning you saw.
 3.  The option will be enabled for people testing packages.

Any comments?

Duncan Murdoch