The following program gives an error message for valid use of an array element in an expression for an automatic character array. The error message is repeated twice. Changing from a run-time subscript in the parameter array to a constant fixes the problem. Dick Hendrickson program try_vf0016 ! fails on Windows XP ! gcc version 4.4.0 20080312 (experimental) [trunk revision 133139] ! syntax error for valid syntax call vf0016( 1, 2, 3) end SUBROUTINE VF0016(nf1,nf2,nf3) CHARACTER(LEN=9,KIND=1),DIMENSION(3), PARAMETER $ :: TEST_STRINGS = $ (/' HI','ABC ',' CDEFG '/) CHARACTER :: TEST_ARRAY $(LEN_TRIM(ADJUSTL(TEST_STRINGS(nf1))), ! changing nf1 to 1 fixes it $ SUM(LEN_TRIM(ADJUSTL(TEST_STRINGS))), $ LEN_TRIM(ADJUSTL(ADJUSTR(TEST_STRINGS(3)))), $ SUM(LEN_TRIM(ADJUSTL(ADJUSTR(TEST_STRINGS(NF1:NF3:NF2))))) ) print *, 2, 10, 5, 7 print *, shape (test_array) end C:\g_experiments\gfortran>gfortran vf0016.f vf0016.f:14.24: $(LEN_TRIM(ADJUSTL(TEST_STRINGS(nf1))), ! changing nf1 to 1 fixes 1 Error: Variable 'test_strings' cannot appear in the expression at (1) vf0016.f:14.24: $(LEN_TRIM(ADJUSTL(TEST_STRINGS(nf1))), ! changing nf1 to 1 fixes 1 Error: Variable 'test_strings' cannot appear in the expression at (1)
Confirmed. A simple patch would be the following: Index: expr.c =================================================================== --- expr.c (Revision 133693) +++ expr.c (Arbeitskopie) @@ -2502,6 +2502,7 @@ check_restricted (gfc_expr *e) || sym->attr.use_assoc || sym->attr.dummy || sym->attr.implied_index + || sym->attr.flavor == FL_PARAMETER || sym->ns != gfc_current_ns || (sym->ns->proc_name != NULL && sym->ns->proc_name->attr.flavor == FL_MODULE) However, this also accepts the following invalid program (note the "i"): program try_vf0016 call vf0016( 1, 2, 3) end SUBROUTINE VF0016(nf1,nf2,nf3) CHARACTER(LEN=9,KIND=1),DIMENSION(3) , PARAMETER $ :: TEST_STRINGS = $ (/' HI','ABC ',' CDEFG '/) integer :: i = 2 CHARACTER :: TEST_ARRAY $(LEN_TRIM(ADJUSTL(TEST_STRINGS(i))), ! changing nf1 to 1 fixes it $ SUM(LEN_TRIM(ADJUSTL(TEST_STRINGS))), $ LEN_TRIM(ADJUSTL(ADJUSTR(TEST_STRINGS(3)))), $ SUM(LEN_TRIM(ADJUSTL(ADJUSTR(TEST_STRINGS(NF1:NF3:NF2))))) ) print *, 2, 10, 5, 7 print *, shape (test_array) end We therefore need to loop over expr->ref and check_restricted() these expressions as well. I think that we can throw in another half a dozen checks as well. ;-)
I guess this is illegal, too: PROGRAM main IMPLICIT NONE CALL test (5, (/ 1, 2, 3, 4, 5, 6, 7, 8, 9 /) ) CONTAINS SUBROUTINE test (n, arr) IMPLICIT NONE INTEGER :: n, arr(:) INTEGER :: i = 5 INTEGER :: local(arr(n)) INTEGER :: local2(arr(i)) ! { dg-error "XXX" } END SUBROUTINE test END PROGRAM main where the definition of local is ok, but local2 is illegal. This program is however accepted with gfortran without your patch. I will implement general checking of the references for EXPR_VARIABLEs that have one.
Subject: Bug 35723 Author: domob Date: Thu Oct 9 07:28:22 2008 New Revision: 141001 URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=141001 Log: 2008-10-09 Daniel Kraft <d@domob.eu> PR fortran/35723 * gfortran.h (gfc_suppress_error): Removed from header. (gfc_push_suppress_errors), (gfc_pop_suppress_errors): New methods. * array.c (gfc_array_size): Use new gfc_push/pop_suppress_errors instead of directly changing gfc_suppress_error. * intrinsic.c (gfc_intrinsic_func_interface): Ditto. (gfc_intrinsic_sub_interface): Ditto. * error.c (suppress_errors): Made static from `gfc_suppress_error'. (gfc_push_suppress_errors), (gfc_pop_suppress_errors): New methods. (gfc_notify_std), (gfc_error): Use new static name of global. * expr.c (check_arglist), (check_references): New methods. (check_restricted): Check arglists and references of EXPR_FUNCTIONs and EXPR_VARAIBALEs, respectively. Allow PARAMETER symbols. 2008-10-09 Daniel Kraft <d@domob.eu> PR fortran/35723 * gfortran.dg/restricted_expression_1.f90: New test. * gfortran.dg/restricted_expression_2.f90: New test. * gfortran.dg/restricted_expression_3.f90: New test. Added: trunk/gcc/testsuite/gfortran.dg/restricted_expression_1.f90 trunk/gcc/testsuite/gfortran.dg/restricted_expression_2.f90 trunk/gcc/testsuite/gfortran.dg/restricted_expression_3.f90 Modified: trunk/gcc/fortran/ChangeLog trunk/gcc/fortran/array.c trunk/gcc/fortran/error.c trunk/gcc/fortran/expr.c trunk/gcc/fortran/gfortran.h trunk/gcc/fortran/intrinsic.c trunk/gcc/testsuite/ChangeLog
Fixed.