Path: utzoo!attcan!uunet!cme!durer!rowe From: rowe@cme.nist.gov (Walter Rowe) Newsgroups: comp.windows.x Subject: X11R4 libraries and -f68881 switch Message-ID: Date: 20 Feb 90 14:44:31 GMT Sender: news@cme.nist.gov Distribution: comp Organization: National Institute of Standards and Technology Lines: 67 OK, here are the responses I have gotten concerning whether you should or should not compile the X11R4 library code with the -f68881 option. The general concensus seems to be that you don't use this option because not all machines have the MC68881 floating point hardware. However, at my site I know that all the sun3 machines do have this, so I have opted to go ahead and use this option. I have other software that requires floating point anyway, so thats the way I am going to go. Others are welcome to read these responses and use them as they like. I would like to thank those who responded for taking the time to do so. Once again, the net has proved to be an invaluable source of information. Thanks to all! Walter Rowe ====================================================================== On Mon, 12 Feb 90, stolcke@jade.berkeley.edu (Andreas Stolcke) said: Andreas> I guess the only reason is that when you have different Andreas> machines on your network, both with and without 68881 Andreas> coprocessors, you don't want to keep two versions of the Andreas> libraries. Compiling with software floating point gives you Andreas> one set of libraries all can use, and since there is not much Andreas> FP intensive stuff in the libs anyway (is there?) that won't Andreas> even hurt your performance. Andreas> BTW, this issue is sort of independent of wether you use cc Andreas> or gcc to compile, both allow you to choose between Andreas> soft-float and 68881 support. cc, however, has the Andreas> additional possibility of switching things and run-time (the Andreas> -fswitch option). ====================================================================== On Tue, 13 Feb 90, mcmacken@watserv1.uwaterloo.ca (John R. F. McMacken) said: John> I used -f68881 on a Sun 3/60 SunOS 4.0.3. No problems so far ... ====================================================================== On Tue, 13 Feb 90, datri@convex.com (Anthony A. Datri) said: Anthony> Not all machines have 68881's -- they were optional for 50's and 60's. ====================================================================== On Tue, 13 Feb 90, mgf@Neon.Stanford.EDU (Michael G. Fitzpatrick) said: Michael> The reason that you do not want to use this flag when Michael> compiling libraries is that every program you may create Michael> later will have to be compiled with this -f68881 flag in Michael> order to successfully link with your libraries. To avoid Michael> this, it is better not to compile with -f68881. By the way, Michael> using gcc with the -m68881 flag does not cause this problem. ====================================================================== On Tue, 13 Feb 90, carlson@lance.tis.llnl.gov (John Carlson) said: John> 1) Sun 3/50s don't have floating point. John> 2) Very little of the server code is floating point, anyway.