Hello world,
Merry Christmas everybody!
This patch resolves one of the remaining F95 bugs by introducing a
temporary for the case
c(:)(1:2) = c(2)(2:3)
It does have the disadvantage that
c(:)(1:2) = c(2)(3:4)
now also creates an unnecessary temporary because gfc_check_dependency
is not smart about substrings. However, I think this is OK for fixing
a wrong-code bug.
I would downgrade the PR to an enhancement request after commiting this
fix, and look at fixing the substring handling.
OK for trunk? What about the other open branches?
Thomas
2014-12-25 Thomas Koenig <tkoe...@gcc.gnu.org>
PR fortran/56867
* trans-array.c (gfc_conv_resolve_dependencies): Also check
dependencies when there may be substrings of character arrays.
2014-12-25 Thomas Koenig <tkoe...@gcc.gnu.org>
PR fortran/56867
* gfortran.dg/dependency_45.f90: New test.
Index: trans-array.c
===================================================================
--- trans-array.c (Revision 219011)
+++ trans-array.c (Arbeitskopie)
@@ -4355,6 +4355,13 @@ gfc_conv_resolve_dependencies (gfc_loopinfo * loop
&& ss_expr->rank)
nDepend = gfc_check_dependency (dest_expr, ss_expr, true);
+ /* Check for cases like c(:)(1:2) = c(2)(2:3) */
+ if (!nDepend && dest_expr->rank > 0
+ && dest_expr->ts.type == BT_CHARACTER
+ && ss_expr->expr_type == EXPR_VARIABLE)
+
+ nDepend = gfc_check_dependency (dest_expr, ss_expr, false);
+
continue;
}
! { dg-do run }
! { dg-options "-Warray-temporaries" }
! PR 56867 - substrings were not checked for dependency.
program main
character(len=4) :: a
character(len=4) :: c(3)
c(1) = 'abcd'
c(2) = '1234'
c(3) = 'wxyz'
c(:)(1:2) = c(2)(2:3) ! { dg-warning "temporary array" }
if (c(3) .ne. '23yz') call abort
end program main
