Xref: utzoo comp.lang.fortran:3838 comp.os.msdos.programmer:1082 Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!usc!csun!Twg-S5!bcphyagi From: bcphyagi@Twg-S5.uucp (Stephen Walton) Newsgroups: comp.lang.fortran,comp.os.msdos.programmer Subject: Re: MS Fortran 5.00 FP underflows Keywords: Microsoft,Fortran Message-ID: <1990Sep22.215355.21417@csun.edu> Date: 22 Sep 90 21:53:55 GMT References: <1990Sep20.215410.4844@csun.edu> <1990Sep21.082155.1743@usenet.ins.cwru.edu> <2150@bnlux0.bnl.gov> Sender: news@csun.edu (News Administrator) Reply-To: srw@csun.edu Organization: Dept. of Physics and Astronomy, Cal State Northridge Lines: 29 In article <2150@bnlux0.bnl.gov> gill@bnlux0.bnl.gov (ronald gill) writes: >I tried to email, but it bounced back. Note my .signature. I've also initialized the Reply-To line. >I had a similar FP problem >with a large program using MicroSoft FORTRAN 4.0... >I solved it by compiling with the HUGE attribute, This occured to me, too. Fact is, the offending program was sending a 150 by 150 REAL array to a routine compiled without the HUGE attribute, though it only used about a 105 by 105 submatrix. I re-dimensioned the array to 127 by 127, reducing its size to less than 64K. Still fails. More news: the test program fails on a no-name Taiwanese Turbo AT clone, but works on a genuine IBM PC/AT and an Everex 386 Step 20. I checked on Compuserve, and there is a Microsoft tech note there about similar trouble. They admit a bug in their compiler, fixed in V5.00 and with the FPFIX disk you can get from Microsoft, involving missing FWAIT instructions. They speculate that AT-type machines, such as old Compaq's, might have ROM BIOS bugs, and specifically mention Phoenix BIOS V1.46 as a problem source. Now, the clone has V3.08 of the ROM BIOS, so that shouldn't be the trouble with my code. Nevertheless, I'm willing to believe, for the moment, that it is a hardware problem and not a Microsoft bug. Any other ideas/suggestions out there? -- Stephen R. Walton, Dept. of Physics and Astronomy, Cal State Northridge I am srw@csun.edu no matter WHAT the stupid From: line says!