Thomas Lumley <[EMAIL PROTECTED]> writes: > On Tue, 5 Aug 2003, Philippe Grosjean wrote: > > > > OK. But I was wondering if people at R-core team, especially those who > > worked on Windows specific aspects, would have in mind some changes they did > > between 1.7.0 and 1.7.1 than can cause this. Since these changes are mainly > > corrections of bugs, the list is hopefully not so long... and it could help > > a lot to have these hints. Thanks very much. > > I checked that the slowdown really was happening in "^", which is > Primitive and so fairly direct. I couldn't find anything remotely > plausible as a cause, though. > > My first guess was something involving the methods package and my second > was a compiler change, so I'm 0-2 so far.
I think we can be fairly sure that the reason is that a new pow() function was injected in the mingw runtime. You can find the actual code in http://cvs.sourceforge.net/cgi-bin/viewcvs.cgi/mingw/runtime/mingwex/math/ *why* this code was inserted is anyones guess. Googling threw up some hint that the MS-supplied pow() was upsetting strtod and causing a regression test failure with the Gimp. The code looks considerably different from the kind of stuff used on Linux though, e.g. it appears not to use FPU transcendentals. I suppose one could ask the author... Also, R is generally compiled with -D NO_MATH_INLINES because of some ancient messup with glibc. I'm not sure whether that is actually still necessary, but it is forcing the use of the non-inlined pow() function. -- O__ ---- Peter Dalgaard Blegdamsvej 3 c/ /'_ --- Dept. of Biostatistics 2200 Cph. N (*) \(*) -- University of Copenhagen Denmark Ph: (+45) 35327918 ~~~~~~~~~~ - ([EMAIL PROTECTED]) FAX: (+45) 35327907 ______________________________________________ [EMAIL PROTECTED] mailing list https://www.stat.math.ethz.ch/mailman/listinfo/r-devel
