Indirect array addressing in a print statement. ifort 17.01

[yossi_stein]

A simple statement: print *,a(b(1:2)) compiles without a complaint,

Command: ifort -check all -debug all -fpe0 -traceback test.f90

but the execution fails, with the message:

Run-Time Check Failure. The variable 'var$21' is being used in 'test.f90(11,1)' without being defined

program test

implicit none

real(8) :: a(2),c(2)

integer :: b(2)

a(1:2)=(/10,20/); b(1:2)=(/1,2/)

print *,a(b(1:2))

end program test

There are other ways to do it: e.g. replacing the print statement by:

c(1:2)=a(b(1:2))

print *,c(1:2)

Prints without a complaint

[Xiaoping_D_Intel]

Thanks for reporting the error. It is a known issue under fixing and the bug report ID is DPD200416730.

Thanks,

Xiaoping Duan

Intel Customer Support

[yossi_stein]

Thanks, Duan,

I would prefer having a compilation error and not a runtime error.

Even a compilation warning, explaining that this is a compiler bug, is much better than

getting this very unpleasant runtime error, which requires a long debugging before daring to call it a compiler bug.

Josef Stein

[jimdempseyatthecove]

>>Even a compilation warning, explaining that this is a compiler bug

I do not think it is possible for the compiler to warn you of bad code generation. If someone has the skill to add this capability, then they could also have the compiler automatically fix the bug.

Jim Dempsey