[Bug fortran/45624] Division by zero compiler error
--- Comment #5 from leftynm at umich dot edu 2010-09-10 16:06 --- Thanks guys. Yeah, I guess my use of PARAMETER wasn't consistent with how it works. I was using it to set a variable such that it cannot be changed. I found a work around though lets me keep it as a PARAMETER, but allows me to compile. PROGRAM test IMPLICIT NONE REAL*8, PARAMETER :: alpha = 0.D0 REAL*8, DIMENSION(5,5) :: matrix INTEGER :: i REAL*8 :: dummy matrix = 0.D0 DO i=1,5 IF (alpha == 0.D0) THEN matrix(i,i) = 0.D0 ELSE dummy = alpha matrix(i,i) = 1.D0/dummy ENDIF ENDDO END PROGRAM This is what I need, since when I don't make my variable a PARAMETER, it causes other problems. This requires less work to fix, so I'm happy with it. I tried PROTECTED, but my code has to be F90 because it's a small part of a bigger project. Thanks to everyone though. I wouldn't have figured this out without your inputs. -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=45624
[Bug fortran/45624] Division by zero compiler error
--- Comment #4 from dominiq at lps dot ens dot fr 2010-09-09 23:20 --- You can use the option -fno-range-check. However, the code itself and the sentence "since I want to protect this variable" in comment #3 let me suspect that you have not understood what PARAMETER is for: a variable with the PARAMETER "attribute" is an alias for its value and exists only during the compilation. What you seem to want is the attribute PROTECTED, i.e. a variable that can be changed only in a specified place as in (F2003 standard draft): An example of the PROTECTED attribute: MODULE temperature REAL, PROTECTED :: temp_c, temp_f CONTAINS SUBROUTINE set_temperature_c(c) REAL, INTENT(IN) :: c temp_c = c temp_f = temp_c*(9.0/5.0) + 32 END SUBROUTINE END MODULE The PROTECTED attribute ensures that the variables temp_c and temp_f cannot be modi ed other than via the set_temperature_c procedure, thus keeping them consistent with each other. The PROTECTED attribute is a f2003 addition, implemented at least from gfortran 4.4. -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=45624
[Bug fortran/45624] Division by zero compiler error
--- Comment #3 from leftynm at umich dot edu 2010-09-09 22:56 --- Ok, if the fact that the variable is a parameter causes this error, I'll have to adjust the rest of my code accordingly to work around this problem. It seems like there should be a better way to fix this, since I want to protect this variable. But, I'll take it. Thanks for the quick reply. -- leftynm at umich dot edu changed: What|Removed |Added Status|UNCONFIRMED |RESOLVED Resolution||WORKSFORME http://gcc.gnu.org/bugzilla/show_bug.cgi?id=45624
[Bug fortran/45624] Division by zero compiler error
--- Comment #2 from kargl at gcc dot gnu dot org 2010-09-09 22:25 --- There is no way to fix this problem unless you would like +inf along the diagonal. gfortran will constant fold 1./alpha if alpha has the parameter attribute. After all, this attribute tells the compiler that alpha is a named constant, ie., it will not change. PS: Fortran bugs are never given a severity high than normal unless the bug breaks bootstrapping the compiler. -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=45624
[Bug fortran/45624] Division by zero compiler error
--- Comment #1 from pinskia at gcc dot gnu dot org 2010-09-09 22:19 --- PARAMETER are special as it is an exact replacement for those variables. -- pinskia at gcc dot gnu dot org changed: What|Removed |Added Severity|major |normal http://gcc.gnu.org/bugzilla/show_bug.cgi?id=45624
