[comp.lang.fortran] Microsoft Fortran 5.0 Optimization Errors?

hepner@cod.NOSC.MIL (Thomas A. Hepner) (01/09/91)

I am in the process of converting a FORTRAN program from the VAX
to the PC using Microsoft fortran 5.0.  The conversion is complete
and the code executes properly (typical numeric intensive complex
number computions done) when optimization is turned off.  However,
when any of the optimization options are selected, the program 
dies with the following error message (running under OS/2 SE1.2):

	"runtime error M6101: MATH
	 -floating-point error: invalid"

The compile and link options used are:
 working version - FL /Lp /Gt /FPi87 /Gt /Od /Zi /Fs /c *.for
		   FL /FeFileName.exe *.obj /Lp /link
 
 error version   - FL /Lp /Gt /FPi87 ?gt /Ox /Fs /c *.for
					   ^
                      any option here causes the above error
                   FL /FeFileName.exe *.obj /Lp /link

Any help on known error with M.S. fortran 5.0 optimization errors
or places to look to determine what is causing the error would me
most appreciated.  (I'm trying to learn how to use codeview to locate
just where the program is dying).

Thanks,

Tom Hepner
hepner@cod.nosc.mil