topic Re:Runtime ifx/ifort compiler bug in Intel® Fortran Compiler

Runtime ifx/ifort compiler bug

NCarlson — Tue, 05 Dec 2023 20:09:52 GMT

The following example produces what I believe is a spurious runtime error. It runs correctly using gfortran. The example involves defined assignment of polymorphic variables and assignment of unlimited polymorphic components.

module foo_class type, abstract :: foo contains procedure, private :: foo_copy generic :: assignment(=) => foo_copy procedure(foo_copy), deferred :: foo_copy_ end type type, extends(foo) :: foo_bar class(*), allocatable :: value contains procedure :: foo_copy_ => foo_bar_copy end type contains subroutine foo_copy(lhs, rhs) class(foo), intent(inout) :: lhs class(foo), intent(in) :: rhs if (same_type_as(lhs, rhs)) then call lhs%foo_copy_(rhs) else error stop end if end subroutine subroutine foo_bar_copy(lhs, rhs) class(foo_bar), intent(inout) :: lhs class(foo), intent(in) :: rhs select type (rhs) type is (foo_bar) print *, 'before foo_bar assignment' lhs%value = rhs%value ! RUNTIME ERROR HERE print *, 'after foo_bar assignment' end select end subroutine end module use foo_class class(foo), allocatable :: src, dest !! Define SRC allocate(foo_bar::src) select type (src) type is (foo_bar) allocate(src%value, source=1) end select !! Copy SRC to DEST allocate(dest, mold=src) print *, 'before foo assignment' dest = src print *, 'after foo assignment' end

The expected results are:

before foo assignment before foo_bar assignment after foo_bar assignment after foo assignment

With ifx I get:

$ ifx -traceback intel-20231205.f90 $ ./a.out before foo assignment before foo_bar assignment forrtl: severe (122): invalid attempt to assign into a pointer that is not associated Image PC Routine Line Source a.out 0000000000408E7F Unknown Unknown Unknown a.out 0000000000405327 foo_bar_copy 34 foo.f90 a.out 0000000000405679 _unnamed_main$$ 54 foo.f90 a.out 000000000040519D Unknown Unknown Unknown libc.so.6 00007F2DA5D6A550 Unknown Unknown Unknown libc.so.6 00007F2DA5D6A609 __libc_start_main Unknown Unknown a.out 00000000004050B5 Unknown Unknown Unknown

The error message involves a pointer but there is not a pointer anywhere in this example.

Re: Runtime ifx/ifort compiler bug

Barbara_P_Intel — Wed, 06 Dec 2023 22:50:09 GMT

I agree. It's a compiler bug.

The good news is that it is fixed in the next minor release of ifx and ifort. It's planned to be released near the end of Q1 2024.

ifx -what -traceback nc.f90 Intel(R) Fortran 24.0-1444 a.out before foo assignment before foo_bar assignment after foo_bar assignment after foo assignment rm a.out ifort -what -traceback nc.f90 ifort: remark #10448: Intel(R) Fortran Compiler Classic (ifort) is now deprecated and will be discontinued late 2024. Intel recommends that customers transition now to using the LLVM-based Intel(R) Fortran Compiler (ifx) for continued Windows* and Linux* support, new language support, new language features, and optimizations. Use '-diag-disable=10448' to disable this message. Intel(R) Fortran 2021.12.0-1425 a.out before foo assignment before foo_bar assignment after foo_bar assignment after foo assignment

Re: Runtime ifx/ifort compiler bug

NCarlson — Thu, 07 Dec 2023 00:18:07 GMT

That's great to hear. Thanks!

Re:Runtime ifx/ifort compiler bug

Barbara_P_Intel — Mon, 01 Apr 2024 16:04:52 GMT

I just confirmed that the runtime error you reported is indeed fixed in ifx 2024.1.0. That version was released last week. Give it a try!