Hi,
I ran into an internal compiler error when implementing a simple linked list containing derived types. I managed to isolate the problem to a trivial test case that reproduces the error. The test program does not do anything useful, it only manages to crash the compiler when compiled.
[bash]MODULE TEST_MOD
IMPLICIT NONE
TYPE TEST_TYPE
CHARACTER(LEN=:), ALLOCATABLE :: STR
END TYPE
END MODULE
MODULE LIST_MOD
USE TEST_MOD
IMPLICIT NONE
TYPE :: LIST
TYPE(TEST_TYPE), POINTER :: OBJ => NULL()
TYPE(LIST), POINTER :: NEXT => NULL()
CONTAINS
PROCEDURE :: TAIL => LIST_TAIL
END TYPE
CONTAINS
FUNCTION LIST_TAIL( THIS )
CLASS(LIST) :: THIS
TYPE(LIST) :: LIST_TAIL
IF (ASSOCIATED( THIS % NEXT ) ) THEN
LIST_TAIL % NEXT => THIS % NEXT % NEXT
LIST_TAIL % OBJ => THIS % NEXT % OBJ
END IF
END FUNCTION
END MODULE
PROGRAM TEST
USE LIST_MOD
IMPLICIT NONE
TYPE(LIST) :: L, TAIL
TAIL = LIST_TAIL(L)
TAIL = L % TAIL()
END PROGRAM[/bash] Compiling this gives the following error message:
ifort test.f90
->
Intel Visual Fortran Compiler Professional for applications running on IA-32, Version 11.1 Build 20091130 Package ID: w_cprof_p_11.1.054
Copyright (C) 1985-2009 Intel Corporation. All rights reserved.
fortcom: Fatal: There has been an internal compiler error (C00000FD).
compilation aborted for test.f90 (code 1)
The problem seems to be compling the call to TAIL type bound procedure with the OO syntax at line 33. If this line is commented out the program compiles nicely.
I found a workaround to the problem. If the LIST_TAIL function is modified to return an allocatable type, the code compiles and works ok.
[bash] FUNCTION LIST_TAIL( THIS )
CLASS(LIST) :: THIS
TYPE(LIST), ALLOCATABLE :: LIST_TAIL
ALLOCATE( LIST_TAIL )
IF (ASSOCIATED( THIS % NEXT ) ) THEN
LIST_TAIL % NEXT => THIS % NEXT % NEXT
LIST_TAIL % OBJ => THIS % NEXT % OBJ
END IF
END FUNCTION
[/bash]
