Dear all,
the initialization of allocatable non-deferred character with NULL
when being a component of a derived type used a wrong path instead
of properly initializing with a null pointer and produced really
weird code.
Regtested on x86_64-pc-linux-gnu. OK for mainline?
While it is a really old bug but wrong code, I'd like to backport
this also at least to 14-branch. Any reservations?
Thanks,
Harald
From f90b21d89c206507c4383e349db12546b793ce31 Mon Sep 17 00:00:00 2001
From: Harald Anlauf
Date: Fri, 7 Feb 2025 21:21:10 +0100
Subject: [PATCH] Fortran: fix initialization of allocatable non-deferred
character [PR59252]
PR fortran/59252
gcc/fortran/ChangeLog:
* trans-expr.cc (gfc_trans_subcomponent_assign): Initialize
allocatable non-deferred character with NULL properly.
gcc/testsuite/ChangeLog:
* gfortran.dg/allocatable_char_1.f90: New test.
---
gcc/fortran/trans-expr.cc | 8 +++-
.../gfortran.dg/allocatable_char_1.f90| 47 +++
2 files changed, 53 insertions(+), 2 deletions(-)
create mode 100644 gcc/testsuite/gfortran.dg/allocatable_char_1.f90
diff --git a/gcc/fortran/trans-expr.cc b/gcc/fortran/trans-expr.cc
index f923aeb9460..a7af67cb441 100644
--- a/gcc/fortran/trans-expr.cc
+++ b/gcc/fortran/trans-expr.cc
@@ -9836,9 +9836,13 @@ gfc_trans_subcomponent_assign (tree dest, gfc_component * cm,
tmp = gfc_trans_alloc_subarray_assign (tmp, cm, expr);
gfc_add_expr_to_block (&block, tmp);
}
- else if (init && cm->attr.allocatable && expr->expr_type == EXPR_NULL)
+ else if (cm->attr.allocatable && expr->expr_type == EXPR_NULL
+ && (init
+ || (cm->ts.type == BT_CHARACTER
+ && !(cm->ts.deferred || cm->attr.pdt_string
{
- /* NULL initialization for allocatable components. */
+ /* NULL initialization for allocatable components.
+ Deferred-length character is dealth with later. */
gfc_add_modify (&block, dest, fold_convert (TREE_TYPE (dest),
null_pointer_node));
}
diff --git a/gcc/testsuite/gfortran.dg/allocatable_char_1.f90 b/gcc/testsuite/gfortran.dg/allocatable_char_1.f90
new file mode 100644
index 000..1d6c25c4942
--- /dev/null
+++ b/gcc/testsuite/gfortran.dg/allocatable_char_1.f90
@@ -0,0 +1,47 @@
+! { dg-do run }
+! { dg-additional-options "-fdump-tree-original" }
+!
+! PR fortran/59252
+
+module mod
+ implicit none
+
+ type t1
+ character(256), allocatable :: label
+ end type t1
+
+ type t2
+ type(t1), allocatable :: appv(:)
+ end type t2
+
+contains
+ subroutine construct(res)
+type(t2), allocatable, intent(inout) :: res
+if (.not. allocated(res)) allocate(res)
+ end subroutine construct
+
+ subroutine construct_appv(appv)
+type(t1), allocatable, intent(inout) :: appv(:)
+if (.not. allocated(appv)) allocate(appv(20))
+ end subroutine construct_appv
+
+ type(t1) function foo () result (res)
+ end function foo
+end module mod
+
+program testy
+ use mod
+ implicit none
+ type(t2), allocatable :: res
+ type(t1) :: s
+
+ ! original test from pr59252
+ call construct (res)
+ call construct_appv(res%appv)
+ deallocate (res)
+
+ ! related test from pr118747 comment 2:
+ s = foo ()
+end program testy
+
+! { dg-final { scan-tree-dump-not "__builtin_memmove" "original" } }
--
2.43.0
