Re: [fpc-devel] FPC 2.0.0 vs FPC 2.0.2 (div by zero)
On 16 mrt 2006, at 03:22, Jose Manuel wrote: Math.SetExceptionMask([exDenormalized,exInvalidOp,exOverflow,e xPrecision,exUnderflow,exZeroDivide]); I do agree it's much polite and cross platform, but doesn't seem to work in Windows XP Pro (only tested in WinXP Pro SP2) with GL 3.2 and FPC 2.0.2 (I've looked everywhere down my PC for a version number, but not found :-), I guess it oughtta be 4.1 but I can't stand for it). Anyway using Set8087CW (which is indeed CPU dependant) does work under my equipment, SetExceptionMask doesn't. SetExceptionMask calls Set8087CW on x86, so if it doesn't work it's because you either use it wrongly, or because it translates its parameters wrongly to the input Set8087CW expects. Jonas ___ fpc-devel maillist - fpc-devel@lists.freepascal.org http://lists.freepascal.org/mailman/listinfo/fpc-devel
RE: [fpc-devel] FPC 2.0.0 vs FPC 2.0.2 (div by zero)
Math.SetExceptionMask([exDenormalized,exInvalidOp,exOverflow,e xPrecision,exUnderflow,exZeroDivide]); [...] stand for it). Anyway using Set8087CW (which is indeed CPU dependant) does work under my equipment, SetExceptionMask doesn't. SetExceptionMask calls Set8087CW on x86, so if it doesn't work it's because you either use it wrongly, or because it translates its parameters wrongly to the input Set8087CW expects. Maybe both :-) I just was calling SetExceptionMask([exZeroDivide]), without qualifying. OK, thanks. I'll check it, and if I find anything odd in parameter translating I will tell. Anyway, don't pay me too much attention, I gotta review it all this weekend, but AFAICR I think I was using the DOS version under Windows XP (not a proper way of doing things ;-(). Sorry for the incoveniences and the loss of time. Anyhow I'll check it up. Thanx, JMR ___ fpc-devel maillist - fpc-devel@lists.freepascal.org http://lists.freepascal.org/mailman/listinfo/fpc-devel
Re: [fpc-devel] FPC 2.0.0 vs FPC 2.0.2 (div by zero)
On Wednesday 15 March 2006 01:55 am, Peter Vreman wrote: Hello, Is there a better way to disable fpu exception other then linking to libc and calling fedisableexcept ??? Set8087CW() in system unit SetExceptionMask() in unit math It was for MacOsX we needed to get rid of libc, I guess Set8087CW($133F) is not CPU independant (PowerPC,x86_64), so I will use Math.SetExceptionMask([exDenormalized,exInvalidOp,exOverflow,exPrecision,exUnderflow,exZeroDivide]); I hope MacOsX is happier now (don't have one, so don't know) kind regards, Den Jean ___ fpc-devel maillist - fpc-devel@lists.freepascal.org http://lists.freepascal.org/mailman/listinfo/fpc-devel
RE: [fpc-devel] FPC 2.0.0 vs FPC 2.0.2 (div by zero)
Set8087CW() in system unit SetExceptionMask() in unit math It was for MacOsX we needed to get rid of libc, I guess Set8087CW($133F) is not CPU independant (PowerPC,x86_64), AFAIK, x86_32 will do too!! so I will use Math.SetExceptionMask([exDenormalized,exInvalidOp,exOverflow,e xPrecision,exUnderflow,exZeroDivide]); I do agree it's much polite and cross platform, but doesn't seem to work in Windows XP Pro (only tested in WinXP Pro SP2) with GL 3.2 and FPC 2.0.2 (I've looked everywhere down my PC for a version number, but not found :-), I guess it oughtta be 4.1 but I can't stand for it). Anyway using Set8087CW (which is indeed CPU dependant) does work under my equipment, SetExceptionMask doesn't. I hope MacOsX is happier now (don't have one, so don't know) Just to make it know (as a primarily Win NT user). I really don't know whether it is as it should be or it should be fixed :-?. A plain Win user as me normally use syscalls to the API, but I'm afraid it's comprimising compatability issues. Masters will tell, I hope :-) kind regards, Regards, JMR ___ fpc-devel maillist - fpc-devel@lists.freepascal.org http://lists.freepascal.org/mailman/listinfo/fpc-devel
Re: [fpc-devel] FPC 2.0.0 vs FPC 2.0.2 (div by zero)
Hello, Is there a better way to disable fpu exception other then linking to libc and calling fedisableexcept ??? thanks a lot, -- Felipe Monteiro de Carvalho ___ fpc-devel maillist - fpc-devel@lists.freepascal.org http://lists.freepascal.org/mailman/listinfo/fpc-devel
Re: [fpc-devel] FPC 2.0.0 vs FPC 2.0.2 (div by zero)
Den Jean wrote: Hi, I have a strange problem. My Qt4 demo program worked fine with FPC 2.0.0, but crashes (div by zero) with FPC 2.0.2. Debugging shows that indeed a div by zero is done within the Qt4 lib. However with FPC 2.0.0 or using C++ code the library isn't bothered with the div by zero. When I use FPC 2.0.2 however it is. Maybe it was FPC 2.0.0 bug (that was fixed in the meantime) that caused this SIGFPE inside qt to be ignored ? AFAIK it was always the intention of FPC that if used library causes a signal like SIGFPE, this signal *will not be ignored* and will cause our program to fail with some exception. Maybe you can workaround this with Set8087CW, just like it has to be workarounded for OpenGL under Windows (see [http://www.freepascal.org/bugs/showrec.php3?ID=3955]). Just add Set8087CW($133F); at the beginning of your program (or even right inside qt unit initialization) and see if it helps. (Note that I'm writing this without any knowledge of qt or your testcase --- I just thought that it may be helpful, sorry if it's not relevant :) ). Michalis ___ fpc-devel maillist - fpc-devel@lists.freepascal.org http://lists.freepascal.org/mailman/listinfo/fpc-devel
Re: [fpc-devel] FPC 2.0.0 vs FPC 2.0.2 (div by zero)
On Wednesday 08 March 2006 10:12 pm, Michalis Kamburelis wrote: Maybe you can workaround this with Set8087CW, just like it has to be see my previous mail So I now use fedisableexcept(FE_ALL_EXCEPT); ___ fpc-devel maillist - fpc-devel@lists.freepascal.org http://lists.freepascal.org/mailman/listinfo/fpc-devel
Re: [fpc-devel] FPC 2.0.0 vs FPC 2.0.2 (div by zero)
(Second send, it seems that mails from my old email address do not reach fpc lists) Den Jean wrote: Hi, I have a strange problem. My Qt4 demo program worked fine with FPC 2.0.0, but crashes (div by zero) with FPC 2.0.2. Debugging shows that indeed a div by zero is done within the Qt4 lib. However with FPC 2.0.0 or using C++ code the library isn't bothered with the div by zero. When I use FPC 2.0.2 however it is. Maybe it was FPC 2.0.0 bug (that was fixed in the meantime) that caused this SIGFPE inside qt to be ignored ? AFAIK it was always the intention of FPC that if used library causes a signal like SIGFPE, this signal *will not be ignored* and will cause our program to fail with some exception. Maybe you can workaround this with Set8087CW, just like it has to be workarounded for OpenGL under Windows (see [http://www.freepascal.org/bugs/showrec.php3?ID=3955]). Just add Set8087CW($133F); at the beginning of your program (or even right inside qt unit initialization) and see if it helps. (Note that I'm writing this without any knowledge of qt or your testcase --- I just thought that it may be helpful, sorry if it's not relevant :) ). Michalis ___ fpc-devel maillist - fpc-devel@lists.freepascal.org http://lists.freepascal.org/mailman/listinfo/fpc-devel
Re: [fpc-devel] FPC 2.0.0 vs FPC 2.0.2 (div by zero)
On Tuesday 07 March 2006 02:45 am, Peter Vreman wrote:
Anyone any idea?
In 2.0.0 the fpu exceptions are disabled if linking to C. In 2.0.2 this is
fixed.
for man G++ it is not the default, I could not find Qt makefile
to disable them, so I was a bit perplex.
(also had integer divisions in mind, quite a difference)
I notice now that even the smallest C++ program has FPE disabled
$ cat test.cpp
#include stdio.h
int main() { printf(FPE test:%f\n,142.0/0.0); }
$ ./a.out
FPE test:inf
So I now use fedisableexcept(FE_ALL_EXCEPT);
in the initialization section of qt4.pas
thx
Den Jean
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Re: [fpc-devel] FPC 2.0.0 vs FPC 2.0.2 (div by zero)
Hi, I have a strange problem. My Qt4 demo program worked fine with FPC 2.0.0, but crashes (div by zero) with FPC 2.0.2. Debugging shows that indeed a div by zero is done within the Qt4 lib. However with FPC 2.0.0 or using C++ code the library isn't bothered with the div by zero. When I use FPC 2.0.2 however it is. I added some writelns euh printfs in the Qt lib: if (p1.x() == p2.x()) printf(Before DIV by Zero: p1.x:%f p2.x: %f\n,p1.x(),p2.x()); edge.m = (p1.y() - p2.y()) / (p1.x() - p2.x()); // this causes the div by zero if (p1.x() == p2.x()) printf(After DIV by Zero: p1.x:%f p2.x: %f\n,p1.x(),p2.x()); with FPC 2.0.2 I get Before DIV by Zero: p1.x:196.50 p2.x:196.50 An unhandled exception occurred at $405CB772 : EDivByZero : Division by zero $405CB772 etc with FPC 2.0.0 or the original C++ demo program I get: Before DIV by Zero: p1.x:196.50 p2.x:196.50 After DIV by Zero: p1.x:196.50 p2.x:196.50 Before DIV by Zero: p1.x:187.50 p2.x:187.50 After DIV by Zero: p1.x:187.50 p2.x:187.50 Before DIV by Zero: p1.x:100.00 p2.x:100.00 After DIV by Zero: p1.x:100.00 p2.x:100.00 and so on, never a crash (but why :-) Anyone any idea? In 2.0.0 the fpu exceptions are disabled if linking to C. In 2.0.2 this is fixed. ___ fpc-devel maillist - fpc-devel@lists.freepascal.org http://lists.freepascal.org/mailman/listinfo/fpc-devel
