re PR fortran/88980 (segfault on allocatable string member assignment)

2019-02-02  Paul Thomas  <pault@gcc.gnu.org>

	PR fortran/88980
	* trans-array.c (gfc_array_init_size): Add element_size to the
	arguments.
	(gfc_array_allocate): Remove the recalculation of the size of
	the element and use element_size from the call to the above.
	Unconditionally set the span field of the descriptor.

2019-02-02  Paul Thomas  <pault@gcc.gnu.org>

	PR fortran/88980
	* gfortran.dg/realloc_on_assign_32.f90 : New test.

From-SVN: r268473

4 files changed, 58 insertions, 39 deletions

diff --git a/gcc/fortran/ChangeLog b/gcc/fortran/ChangeLog
index 1dc007d..6dba135 100644
--- a/gcc/fortran/ChangeLog
+++ b/gcc/fortran/ChangeLog
@@ -1,5 +1,14 @@
 2019-02-02  Paul Thomas  <pault@gcc.gnu.org>
 
+	PR fortran/88980
+	* trans-array.c (gfc_array_init_size): Add element_size to the
+	arguments.
+	(gfc_array_allocate): Remove the recalculation of the size of
+	the element and use element_size from the call to the above.
+	Unconditionally set the span field of the descriptor.
+
+2019-02-02  Paul Thomas  <pault@gcc.gnu.org>
+
 	PR fortran/88685
 	* expr.c (is_subref_array): Move the check for class pointer
 	dummy arrays to after the reference check. If we haven't seen
diff --git a/gcc/fortran/trans-array.c b/gcc/fortran/trans-array.c
index 6d7c3d2..b885fe6 100644
--- a/gcc/fortran/trans-array.c
+++ b/gcc/fortran/trans-array.c
@@ -5370,14 +5370,14 @@ gfc_array_init_size (tree descriptor, int rank, int corank, tree * poffset,
 		     gfc_expr ** lower, gfc_expr ** upper, stmtblock_t * pblock,
 		     stmtblock_t * descriptor_block, tree * overflow,
 		     tree expr3_elem_size, tree *nelems, gfc_expr *expr3,
-		     tree expr3_desc, bool e3_has_nodescriptor, gfc_expr *expr)
+		     tree expr3_desc, bool e3_has_nodescriptor, gfc_expr *expr,
+		     tree *element_size)
 {
   tree type;
   tree tmp;
   tree size;
   tree offset;
   tree stride;
-  tree element_size;
   tree or_expr;
   tree thencase;
   tree elsecase;
@@ -5628,10 +5628,10 @@ gfc_array_init_size (tree descriptor, int rank, int corank, tree * poffset,
     tmp = TYPE_SIZE_UNIT (gfc_get_element_type (type));
 
   /* Convert to size_t.  */
-  element_size = fold_convert (size_type_node, tmp);
+  *element_size = fold_convert (size_type_node, tmp);
 
   if (rank == 0)
-    return element_size;
+    return *element_size;
 
   *nelems = gfc_evaluate_now (stride, pblock);
   stride = fold_convert (size_type_node, stride);
@@ -5641,14 +5641,14 @@ gfc_array_init_size (tree descriptor, int rank, int corank, tree * poffset,
      dividing.  */
   tmp = fold_build2_loc (input_location, TRUNC_DIV_EXPR,
 			 size_type_node,
-			 TYPE_MAX_VALUE (size_type_node), element_size);
+			 TYPE_MAX_VALUE (size_type_node), *element_size);
   cond = gfc_unlikely (fold_build2_loc (input_location, LT_EXPR,
 					logical_type_node, tmp, stride),
 		       PRED_FORTRAN_OVERFLOW);
   tmp = fold_build3_loc (input_location, COND_EXPR, integer_type_node, cond,
 			 integer_one_node, integer_zero_node);
   cond = gfc_unlikely (fold_build2_loc (input_location, EQ_EXPR,
-					logical_type_node, element_size,
+					logical_type_node, *element_size,
 					build_int_cst (size_type_node, 0)),
 		       PRED_FORTRAN_SIZE_ZERO);
   tmp = fold_build3_loc (input_location, COND_EXPR, integer_type_node, cond,
@@ -5658,7 +5658,7 @@ gfc_array_init_size (tree descriptor, int rank, int corank, tree * poffset,
   *overflow = gfc_evaluate_now (tmp, pblock);
 
   size = fold_build2_loc (input_location, MULT_EXPR, size_type_node,
-			  stride, element_size);
+			  stride, *element_size);
 
   if (poffset != NULL)
     {
@@ -5736,6 +5736,7 @@ gfc_array_allocate (gfc_se * se, gfc_expr * expr, tree status, tree errmsg,
   tree var_overflow = NULL_TREE;
   tree cond;
   tree set_descriptor;
+  tree element_size = NULL_TREE;
   stmtblock_t set_descriptor_block;
   stmtblock_t elseblock;
   gfc_expr **lower;
@@ -5852,7 +5853,7 @@ gfc_array_allocate (gfc_se * se, gfc_expr * expr, tree status, tree errmsg,
 			      &offset, lower, upper,
 			      &se->pre, &set_descriptor_block, &overflow,
 			      expr3_elem_size, nelems, expr3, e3_arr_desc,
-			      e3_has_nodescriptor, expr);
+			      e3_has_nodescriptor, expr, &element_size);
 
   if (dimension)
     {
@@ -5924,38 +5925,11 @@ gfc_array_allocate (gfc_se * se, gfc_expr * expr, tree status, tree errmsg,
 
   gfc_add_expr_to_block (&se->pre, tmp);
 
-  /* Update the array descriptors.  */
+  /* Update the array descriptor with the offset and the span.  */
   if (dimension)
-    gfc_conv_descriptor_offset_set (&set_descriptor_block, se->expr, offset);
-
-  /* Set the span field for pointer and deferred length character arrays.  */
-  if ((is_pointer_array (se->expr)
-       || (expr->ts.type == BT_CLASS && CLASS_DATA (expr)->attr.class_pointer)
-       || (expr->ts.type == BT_CHARACTER && TREE_CODE (se->string_length)
-							== COMPONENT_REF))
-      || (expr->ts.type == BT_CHARACTER
-	  && (expr->ts.deferred || VAR_P (expr->ts.u.cl->backend_decl))))
-    {
-      if (expr3 && expr3_elem_size != NULL_TREE)
-	tmp = expr3_elem_size;
-      else if (se->string_length
-	       && (TREE_CODE (se->string_length) == COMPONENT_REF
-		   || (expr->ts.type == BT_CHARACTER && expr->ts.deferred)))
-	{
-	  if (expr->ts.kind != 1)
-	    {
-	      tmp = build_int_cst (gfc_array_index_type, expr->ts.kind);
-	      tmp = fold_build2_loc (input_location, MULT_EXPR,
-				    gfc_array_index_type, tmp,
-				    fold_convert (gfc_array_index_type,
-						  se->string_length));
-	    }
-	  else
-	    tmp = se->string_length;
-	}
-      else
-	tmp = TYPE_SIZE_UNIT (gfc_get_element_type (TREE_TYPE (se->expr)));
-      tmp = fold_convert (gfc_array_index_type, tmp);
+    {
+      gfc_conv_descriptor_offset_set (&set_descriptor_block, se->expr, offset);
+      tmp = fold_convert (gfc_array_index_type, element_size);
       gfc_conv_descriptor_span_set (&set_descriptor_block, se->expr, tmp);
     }
 
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index bc9ca4c..d94a3be 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,5 +1,10 @@
 2019-02-02  Paul Thomas  <pault@gcc.gnu.org>
 
+	PR fortran/88980
+	* gfortran.dg/realloc_on_assign_32.f90 : New test.
+
+2019-02-02  Paul Thomas  <pault@gcc.gnu.org>
+
 	PR fortran/88685
 	* gfortran.dg/pointer_array_component_3.f90 : New test.
 
diff --git a/gcc/testsuite/gfortran.dg/realloc_on_assign_32.f90 b/gcc/testsuite/gfortran.dg/realloc_on_assign_32.f90
new file mode 100644
index 0000000..31a0d76
--- /dev/null
+++ b/gcc/testsuite/gfortran.dg/realloc_on_assign_32.f90
@@ -0,0 +1,31 @@
+! { dg-do run }
+!
+! Test the fix for PR88980 in which the 'span' field if the descriptor
+! for 'Items' was not set, causing the assignment to segfault.
+!
+! Contributed by Antony Lewis  <antony@cosmologist.info>
+!
+program tester
+  call gbug
+contains
+  subroutine gbug
+    type TNameValue
+      character(LEN=:), allocatable :: Name
+    end type TNameValue
+
+    type TNameValue_pointer
+      Type(TNameValue), allocatable :: P
+    end type TNameValue_pointer
+
+    Type TType
+      type(TNameValue_pointer), dimension(:), allocatable :: Items
+    end type TType
+    Type(TType) T
+
+    allocate(T%Items(2))
+    allocate(T%Items(2)%P)
+    T%Items(2)%P%Name =  'test'
+    if (T%Items(2)%P%Name .ne.  'test') stop 1
+
+  end subroutine gbug
+end program tester