SGESV use changing iteration number

[Surabhi_S]

Hi, 

I am using MS Visual Studios with Intel oneAPI compiler to develop a code in Fortran 77. I am calling sgesv inside a loop. However, as soon as I step over this function, my iteration number of the loop changes from 1 to 263 (or some high number like that). I have also attempted to replace this function with SGETRF and SGETRS (implemented together) but I am getting the same error. I am not able to share the code but here are some descriptions that might help:

Do ITVAL = 1,ITMAX         (itmax is defined)

.

.

.

CALL sgesv(NT,1,C,NPMAX,IPIV,D,NPMAX,info)

.

NT is an integer, NPMAX is a parameter, C and D are REAL ITVAL changes it's value from 1 to 200 something here

.

.

End Do

Any help regarding this will be greatly appreciated. Thank you!

[mecej4]

The Lapack library gets very high usage, and the probability that SGESV has a bug is close to zero. If, as you claim, a call to SGESV causes changes to a non-argument variable that is not in scope in the called routine, that indicates a serious error in the declarations of the arguments passed to SGESV. Show us the declarations of the eight actual arguments, and see if the values of those arguments meet the requirements of the SGESV routine.