2019-03-03 Thomas Koenig <tkoenig@gcc.gnu.org>

	PR fortran/89174
	Backport from trunk
	* trans-expr.c (gfc_find_and_cut_at_last_class_ref): Add is_mold
	to garguments. If we are dealing with a MOLD, call
	gfc_expr_to_initialize().
	* trans-stmt.c (gfc_trans_allocate): For MOLD, pass is_mold=true
	to gfc_find_and_cut_at_last_class_ref.
	* trans.h (gfc_find_and_cut_at_last_class_ref): Add optional
	argument is_mold with default false.

2019-03-03  Thomas Koenig  <tkoenig@gcc.gnu.org>

	PR fortran/89174
	Backport from trunk
	* gfortran.dg/allocate_with_mold_3.f90: New test.



git-svn-id: https://gcc.gnu.org/svn/gcc/branches/gcc-8-branch@269351 138bc75d-0d04-0410-961f-82ee72b054a4

6 files changed, 46 insertions, 4 deletions

diff --git a/gcc/fortran/ChangeLog b/gcc/fortran/ChangeLog
index 62d70465edf..c5624af2328 100644
--- a/gcc/fortran/ChangeLog
+++ b/gcc/fortran/ChangeLog
@@ -1,5 +1,17 @@
 2019-03-03  Thomas Koenig  <tkoenig@gcc.gnu.org>
 
+	PR fortran/89174
+	Backport from trunk
+	* trans-expr.c (gfc_find_and_cut_at_last_class_ref): Add is_mold
+	to garguments. If we are dealing with a MOLD, call
+	gfc_expr_to_initialize().
+	* trans-stmt.c (gfc_trans_allocate): For MOLD, pass is_mold=true
+	to gfc_find_and_cut_at_last_class_ref.
+	* trans.h (gfc_find_and_cut_at_last_class_ref): Add optional
+	argument is_mold with default false.
+
+2019-03-03  Thomas Koenig  <tkoenig@gcc.gnu.org>
+
 	PR fortran/87689
 	Backport from trunk
 	* gfortran.dg/lto/20091028-1_0.f90: Add -Wno-lto-type-mismatch to
diff --git a/gcc/fortran/trans-expr.c b/gcc/fortran/trans-expr.c
index 4ef9d8953d1..b95cf8ddc4f 100644
--- a/gcc/fortran/trans-expr.c
+++ b/gcc/fortran/trans-expr.c
@@ -352,7 +352,7 @@ gfc_vptr_size_get (tree vptr)
    of refs following.  */
 
 gfc_expr *
-gfc_find_and_cut_at_last_class_ref (gfc_expr *e)
+gfc_find_and_cut_at_last_class_ref (gfc_expr *e, bool is_mold)
 {
   gfc_expr *base_expr;
   gfc_ref *ref, *class_ref, *tail = NULL, *array_ref;
@@ -394,7 +394,10 @@ gfc_find_and_cut_at_last_class_ref (gfc_expr *e)
       e->ref = NULL;
     }
 
-  base_expr = gfc_copy_expr (e);
+  if (is_mold)
+    base_expr = gfc_expr_to_initialize (e);
+  else
+    base_expr = gfc_copy_expr (e);
 
   /* Restore the original tail expression.  */
   if (class_ref)
diff --git a/gcc/fortran/trans-stmt.c b/gcc/fortran/trans-stmt.c
index 5b2d4e8279d..eb976c70a3a 100644
--- a/gcc/fortran/trans-stmt.c
+++ b/gcc/fortran/trans-stmt.c
@@ -6606,7 +6606,7 @@ gfc_trans_allocate (gfc_code * code)
 	  /* Use class_init_assign to initialize expr.  */
 	  gfc_code *ini;
 	  ini = gfc_get_code (EXEC_INIT_ASSIGN);
-	  ini->expr1 = gfc_find_and_cut_at_last_class_ref (expr);
+	  ini->expr1 = gfc_find_and_cut_at_last_class_ref (expr, true);
 	  tmp = gfc_trans_class_init_assign (ini);
 	  gfc_free_statements (ini);
 	  gfc_add_expr_to_block (&block, tmp);
diff --git a/gcc/fortran/trans.h b/gcc/fortran/trans.h
index 5a2c2352a77..103ad6787ad 100644
--- a/gcc/fortran/trans.h
+++ b/gcc/fortran/trans.h
@@ -412,7 +412,7 @@ tree gfc_class_data_get (tree);
 tree gfc_class_vptr_get (tree);
 tree gfc_class_len_get (tree);
 tree gfc_class_len_or_zero_get (tree);
-gfc_expr * gfc_find_and_cut_at_last_class_ref (gfc_expr *);
+gfc_expr * gfc_find_and_cut_at_last_class_ref (gfc_expr *, bool is_mold = false);
 /* Get an accessor to the class' vtab's * field, when a class handle is
    available.  */
 tree gfc_class_vtab_hash_get (tree);
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index cb7ac79afdb..f7b780a3ce4 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,5 +1,11 @@
 2019-03-03  Thomas Koenig  <tkoenig@gcc.gnu.org>
 
+	PR fortran/89174
+	Backport from trunk
+	* gfortran.dg/allocate_with_mold_3.f90: New test.
+
+2019-03-03  Thomas Koenig  <tkoenig@gcc.gnu.org>
+
 	PR fortran/87689
 	Backport from trunk
 	* gfortran.dg/lto/20091028-1_0.f90: Add -Wno-lto-type-mismatch to
diff --git a/gcc/testsuite/gfortran.dg/allocate_with_mold_3.f90 b/gcc/testsuite/gfortran.dg/allocate_with_mold_3.f90
new file mode 100644
index 00000000000..797edbe7d49
--- /dev/null
+++ b/gcc/testsuite/gfortran.dg/allocate_with_mold_3.f90
@@ -0,0 +1,21 @@
+! { dg-do  run }
+! PR fortran/89174 - this used to segfault on execution.
+! Test case by Neil Carlson.
+module mod
+  type :: array_data
+    class(*), allocatable :: mold
+  contains
+    procedure :: push
+  end type
+contains
+  subroutine push(this, value)
+    class(array_data), intent(inout) :: this
+    class(*), intent(in) :: value
+    allocate(this%mold, mold=value) ! <== SEGFAULTS HERE
+  end subroutine
+end module
+
+use mod
+type(array_data) :: foo
+call foo%push(42)
+end