This problem was caused by the compiler attempting to use 0 as an lvalue
and to assign 0 to it. Understandably, this upset the gimplifer quite a bit
:-) The fix is to use the ss_info string length for deferred length
character components, where the hidden string length component has been
used. The use of a constant as an lvalue is prevented by checking that the
expression string length is a variable.
Regtests on FC33/x86_64 - OK for all three branches?
Paul
Fortran: Fix for class defined operators [PR99125].
2021-02-23 Paul Thomas <pa...@gcc.gnu.org>
gcc/fortran
PR fortran/99125
* trans-array.c (gfc_conv_expr_descriptor): For deferred length
length components use the ss_info string length instead of
gfc_get_expr_charlen. Make sure that the deferred string length
is a variable before assigning to it. Otherwise use the expr.
* trans-expr.c (gfc_conv_string_length): Make sure that the
deferred string length is a variable before assigning to it.
gcc/testsuite/
PR fortran/99125
* gfortran.dg/alloc_deferred_comp_1.f90: New test.
diff --git a/gcc/fortran/trans-array.c b/gcc/fortran/trans-array.c
index c6725659093..e85d63c3539 100644
--- a/gcc/fortran/trans-array.c
+++ b/gcc/fortran/trans-array.c
@@ -7670,15 +7670,21 @@ gfc_conv_expr_descriptor (gfc_se *se, gfc_expr *expr)
/* Set the string_length for a character array. */
if (expr->ts.type == BT_CHARACTER)
{
- se->string_length = gfc_get_expr_charlen (expr);
+ if (deferred_array_component)
+ se->string_length = ss_info->string_length;
+ else
+ se->string_length = gfc_get_expr_charlen (expr);
+
if (VAR_P (se->string_length)
&& expr->ts.u.cl->backend_decl == se->string_length)
tmp = ss_info->string_length;
else
tmp = se->string_length;
- if (expr->ts.deferred)
+ if (expr->ts.deferred && VAR_P (expr->ts.u.cl->backend_decl))
gfc_add_modify (&se->pre, expr->ts.u.cl->backend_decl, tmp);
+ else
+ expr->ts.u.cl->backend_decl = tmp;
}
/* If we have an array section, are assigning or passing an array
diff --git a/gcc/fortran/trans-expr.c b/gcc/fortran/trans-expr.c
index e61492485b8..9d178360fc3 100644
--- a/gcc/fortran/trans-expr.c
+++ b/gcc/fortran/trans-expr.c
@@ -2471,7 +2471,7 @@ gfc_conv_string_length (gfc_charlen * cl, gfc_expr * expr, stmtblock_t * pblock)
se.expr, build_zero_cst (TREE_TYPE (se.expr)));
gfc_add_block_to_block (pblock, &se.pre);
- if (cl->backend_decl)
+ if (cl->backend_decl && VAR_P (cl->backend_decl))
gfc_add_modify (pblock, cl->backend_decl, se.expr);
else
cl->backend_decl = gfc_evaluate_now (se.expr, pblock);
! { dg-do run }
!
! Test the fix for PR99125, where the array reference in the print
! statement caused an ICE because the gimplifier complained about '0'
! being used as an lvalue.
!
! Contributed by Gerhard Steinmetz <gs...@t-online.de>
!
program p
type t
character(:), allocatable :: a(:)
end type
type(t) :: x
character(8) :: c(3) = ['12 45 78','23 56 89','34 67 90']
x%a = c
if (any (x%a(2:3) .ne. ['23 56 89','34 67 90'])) stop 1
if (any (x%a(2:3)(4:5) .ne. ['56','67'])) stop 2 ! Bizarrely this worked.
end
