[Bug fortran/98701] I compiled a program with gfortran on Mac (Big Sur, version 11.1) and g77 on Windows 10. I get two very different results for identical input files with the results from the one c
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98701 --- Comment #16 from Bahram.shahrooz at uc dot edu --- I spent a good chunk of today to debug. The culprit was two variables that had not been set equal to 0. I get the same results with g77 on Windows, GFortran on Mac Big Sur, & AbsoftTools ( I downloaded a trial version to help me debug) on Mac Big Sur You guys are so helpful. I truly appreciate your time and.
[Bug fortran/98701] I compiled a program with gfortran on Mac (Big Sur, version 11.1) and g77 on Windows 10. I get two very different results for identical input files with the results from the one c
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98701 Thomas Koenig changed: What|Removed |Added CC||tkoenig at gcc dot gnu.org --- Comment #15 from Thomas Koenig --- Just one final remark. Using gfortran -O2 -Wall FiberAnalysis.f will give you FiberAnalysis.f:146:72: 146 | if(eincr.gt.0) xnumber=(esfinal-estart)/eincr | ^ Warnung: »estart« may be used uninitialized [-Wmaybe-uninitialized] FiberAnalysis.f:146:44: 146 | if(eincr.gt.0) xnumber=(esfinal-estart)/eincr |^ Hinweis: »estart« ist hier deklariert FiberAnalysis.f:148:9: 148 | if(xnumber.gt.500) then | ^ Warnung: »xnumber« könnte in dieser Funktion uninitialisiert verwendet werden [-Wmaybe-uninitialized] which pretty well shows where problems could occur.
[Bug fortran/98701] I compiled a program with gfortran on Mac (Big Sur, version 11.1) and g77 on Windows 10. I get two very different results for identical input files with the results from the one c
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98701 kargl at gcc dot gnu.org changed: What|Removed |Added Resolution|--- |INVALID Status|UNCONFIRMED |RESOLVED --- Comment #14 from kargl at gcc dot gnu.org --- The code uses undefined variables. With g77, these seem to be initialized to some value. If -freal-init=nan is used, the compiled program dies quickly. In other words, the bug is in the program not gfortran.
[Bug fortran/98701] I compiled a program with gfortran on Mac (Big Sur, version 11.1) and g77 on Windows 10. I get two very different results for identical input files with the results from the one c
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98701 --- Comment #13 from Bahram.shahrooz at uc dot edu --- Thank you for your help. I really appreciate your time.
[Bug fortran/98701] I compiled a program with gfortran on Mac (Big Sur, version 11.1) and g77 on Windows 10. I get two very different results for identical input files with the results from the one c
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98701 --- Comment #12 from Steve Kargl --- On Sat, Jan 16, 2021 at 11:20:20PM +, Bahram.shahrooz at uc dot edu wrote: > > Do you've any suggestions for how to trace the source > of error so I can fix the code? > Not really. I suppose old fashion debugging is needed where you put 'print' statements into the code to check intermediate results. As far as I can tell, you simply are using undefined variables in the code. This isn't a gfortran bug, so the bug report will be closed.
[Bug fortran/98701] I compiled a program with gfortran on Mac (Big Sur, version 11.1) and g77 on Windows 10. I get two very different results for identical input files with the results from the one c
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98701 --- Comment #11 from Bahram.shahrooz at uc dot edu --- Thanks! This is how I compiled: gfortran FiberAnalysis.f -finit-real=nan -fcheck=all -ffpe-trap=zero,invalid -o FiberAnalysis_v2 This what I get after running (the answers are correct): Program received signal SIGFPE: Floating-point exception - erroneous arithmetic operation. Backtrace for this error: #0 0x105c4ad3d #1 0x105c4a16d #2 0x7fff203c4d7c #3 0x105c34e45 #4 0x105c3c653 #5 0x105c3cae6 zsh: floating point exception /Users/bahram/FiberAnalysis_v2 Saving session... ...copying shared history... ...saving history...truncating history files... ...completed. Deleting expired sessions...none found. Do you've any suggestions for how to trace the source of error so I can fix the code?
[Bug fortran/98701] I compiled a program with gfortran on Mac (Big Sur, version 11.1) and g77 on Windows 10. I get two very different results for identical input files with the results from the one c
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98701 --- Comment #10 from Steve Kargl --- On Sat, Jan 16, 2021 at 04:48:09AM +, Bahram.shahrooz at uc dot edu wrote: > https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98701 > > --- Comment #9 from Bahram.shahrooz at uc dot edu --- > Yes, thank you for finding this bug. Things didn't change after changing > estart > to estrt. > > Sorry, I don't know how to use -freal-init=nan. I tried to use it like this > but got an error. > > % gfortran FiberAnalysis.f -freal-init=nan -o FiberAnalysis > > gfortran: error: unrecognized command-line option '-freal-init=nan' > Whoops. It helps if I spell it right. -finit-real=nan
[Bug fortran/98701] I compiled a program with gfortran on Mac (Big Sur, version 11.1) and g77 on Windows 10. I get two very different results for identical input files with the results from the one c
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98701 --- Comment #9 from Bahram.shahrooz at uc dot edu --- Yes, thank you for finding this bug. Things didn't change after changing estart to estrt. Sorry, I don't know how to use -freal-init=nan. I tried to use it like this but got an error. % gfortran FiberAnalysis.f -freal-init=nan -o FiberAnalysis gfortran: error: unrecognized command-line option '-freal-init=nan'
[Bug fortran/98701] I compiled a program with gfortran on Mac (Big Sur, version 11.1) and g77 on Windows 10. I get two very different results for identical input files with the results from the one c
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98701 --- Comment #8 from Steve Kargl --- On Fri, Jan 15, 2021 at 05:21:22PM -0800, Steve Kargl wrote: > > You're using undefined variables. > I little more debugging, read(5,*) estrt,esfinal,eincr if(eincr.gt.0) xnumber=(esfinal-estart)/eincr estart is undefined here. I suspect you want estrt.
[Bug fortran/98701] I compiled a program with gfortran on Mac (Big Sur, version 11.1) and g77 on Windows 10. I get two very different results for identical input files with the results from the one c
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98701 --- Comment #7 from Steve Kargl --- On Sat, Jan 16, 2021 at 12:51:38AM +, Bahram.shahrooz at uc dot edu wrote: > https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98701 > > --- Comment #6 from Bahram.shahrooz at uc dot edu --- > I get wrong answers doing this: > > gfortran FiberAnalysis.f -o FiberAnalysis > > I get correct answers doing this: > > gfortran FiberAnalysis.f -fcheck=all -ffpe-trap=zero,invalid -o FiberAnalysis > Your code is broken. I added -freal-init=nan to initialize all variables to an NaN. The compiled program dies, and the debugger shows % gdb ./z z.core Program terminated with signal SIGFPE, Arithmetic exception. #0 0x08049476 in fsteel1 (es=nan(0x8), fs=nan(0x8), ibuckle=0) at FiberAnalysis.f:387 387 if(es.ge.0.0) go to 10 (gdb) p es $1 = nan(0x8) If I reduce the loop 'do 3000 na=1,500' by 1, i.e., I use 'do 3000 na=1,499', then the computation dies at (gdb) bt #0 0x0804e323 in fiberanalysis () at FiberAnalysis.f:313 #1 0x0804ed63 in main (argc=1, argv=0xffbfe864) at FiberAnalysis.f:361 #2 0x08048a37 in _start1 () #3 0x08048b90 in _start () Line 313 is if(xp(k).ne.0.and.xp(k).ge.xpmin) then and (gdb) p xp(500) $4 = nan(0x8) (gdb) p xp(499) $5 = 2425.0013590651233 If I reduce the loop to 498, it then dies at Program terminated with signal SIGFPE, Arithmetic exception. #0 0x0804e08b in fiberanalysis () at FiberAnalysis.f:302 302 if(xp(k).lt.xpmin) then (gdb) p xp(498) $1 = 2424.590579331998 (gdb) p xp(499) $2 = nan(0x8) You're using undefined variables.
[Bug fortran/98701] I compiled a program with gfortran on Mac (Big Sur, version 11.1) and g77 on Windows 10. I get two very different results for identical input files with the results from the one c
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98701 --- Comment #6 from Bahram.shahrooz at uc dot edu --- I get wrong answers doing this: gfortran FiberAnalysis.f -o FiberAnalysis I get correct answers doing this: gfortran FiberAnalysis.f -fcheck=all -ffpe-trap=zero,invalid -o FiberAnalysis Moment Axial_Load 3244.08910-215.38970 3432.22199-190.65966 3594.93500-168.86785 3734.50302-149.77519 3842.77168-134.14558 3986.24344-114.80934 4115.25069 -97.21038 4230.37015 -81.27311 4323.74191 -67.84354 4442.09009 -51.57463 4551.67144 -36.41379 4653.40529 -22.24901 4748.46682 -8.91886 4844.11684 4.77310 4933.55651 17.64818 5017.35901 29.77892 5097.44257 41.41472 5193.49624 55.17913 5275.53074 67.17330 5351.16344 78.34124
[Bug fortran/98701] I compiled a program with gfortran on Mac (Big Sur, version 11.1) and g77 on Windows 10. I get two very different results for identical input files with the results from the one c
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98701 --- Comment #5 from Steve Kargl --- On Sat, Jan 16, 2021 at 12:41:56AM +, Bahram.shahrooz at uc dot edu wrote: > https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98701 > > --- Comment #4 from Bahram.shahrooz at uc dot edu --- > I compiled with the suggested options (below) and now the code gives the same > result as g77. > > -fcheck=all -ffpe-trap=zero,invalid > > Things look good now! > Those options should not fix the code. Those should find the error. If you compile without these options, do you then get wrong results. Also, what do you expect. On my system, I see Moment Axial_Load 1470.43183 134.34887 1564.87796 144.02005 1643.96121 152.13968 1708.47908 158.75645 1749.07356 162.94978 for the first few lines.
[Bug fortran/98701] I compiled a program with gfortran on Mac (Big Sur, version 11.1) and g77 on Windows 10. I get two very different results for identical input files with the results from the one c
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98701 --- Comment #4 from Bahram.shahrooz at uc dot edu --- I compiled with the suggested options (below) and now the code gives the same result as g77. -fcheck=all -ffpe-trap=zero,invalid Things look good now! Sorry for starting this bug report prematurely, and many thanks for your help!!!
[Bug fortran/98701] I compiled a program with gfortran on Mac (Big Sur, version 11.1) and g77 on Windows 10. I get two very different results for identical input files with the results from the one c
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98701 --- Comment #3 from Bahram.shahrooz at uc dot edu --- Created attachment 49979 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=49979&action=edit source code Sorry, I had to zip several files. Readme file in Archive.zip explains what the files are. Here's how I compiled: gfortran FiberAnalysis.f -o0 -o FiberAnalysis g77 -o0 FiberAnalysis.f -o FiberAnalysis
[Bug fortran/98701] I compiled a program with gfortran on Mac (Big Sur, version 11.1) and g77 on Windows 10. I get two very different results for identical input files with the results from the one c
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98701 Jakub Jelinek changed: What|Removed |Added CC||jakub at gcc dot gnu.org --- Comment #2 from Jakub Jelinek --- And given the warnings, if the code uses exact floating point comparisons, it might behave differently if there is even 1 ulp difference (which is quite possible on a lot of code).
[Bug fortran/98701] I compiled a program with gfortran on Mac (Big Sur, version 11.1) and g77 on Windows 10. I get two very different results for identical input files with the results from the one c
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98701 kargl at gcc dot gnu.org changed: What|Removed |Added CC||kargl at gcc dot gnu.org --- Comment #1 from kargl at gcc dot gnu.org --- We need 1) Course code and input file 2) Expected output generated by g77 on Windows 10. Command line used to compile code. 3) Output you go on Mac. With gfortran, try compiling with -fcheck=all -ffpe-trap=zero,invalid
