[patch] Fix Fortran size_t parameter passing

[Andrew Stubbs]

This patch fixes a bug observed on amdgcn in which the Fortran frontend 
creates function calls using the 32-bit parameters where they ought to 
be 64-bit, resulting in UB.

The issue is caused by the use of "integer_zero_node" where the 
definition of the function calls for "size_zero_node". I presume this 
works on other architectures because the types are the same size, or 
else because parameters are always 64-bit wide.

OK to commit?

Andrew
Fix fortran size_t parameter passing.

2019-05-22  Andrew Stubbs  <a...@codesourcery.com>

	gcc/fortran/
	* trans-stmt.c (gfc_trans_critical): Use size_zero_node for
	gfor_fndecl_caf_lock and gfor_fndecl_caf_unlock calls.
	(gfc_trans_allocate): Use size_zero_node for gfor_fndecl_caf_sync_all
	call.

diff --git a/gcc/fortran/trans-stmt.c b/gcc/fortran/trans-stmt.c
index 5fa182bf05a..4314a1edb90 100644
--- a/gcc/fortran/trans-stmt.c
+++ b/gcc/fortran/trans-stmt.c
@@ -1579,9 +1579,9 @@ gfc_trans_critical (gfc_code *code)
       token = gfc_get_symbol_decl (code->resolved_sym);
       token = GFC_TYPE_ARRAY_CAF_TOKEN (TREE_TYPE (token));
       tmp = build_call_expr_loc (input_location, gfor_fndecl_caf_lock, 7,
-				 token, integer_zero_node, integer_one_node,
+				 token, size_zero_node, integer_one_node,
 				 null_pointer_node, null_pointer_node,
-				 null_pointer_node, integer_zero_node);
+				 null_pointer_node, size_zero_node);
       gfc_add_expr_to_block (&block, tmp);
 
       /* It guarantees memory consistency within the same segment */
@@ -1602,9 +1602,9 @@ gfc_trans_critical (gfc_code *code)
   if (flag_coarray == GFC_FCOARRAY_LIB)
     {
       tmp = build_call_expr_loc (input_location, gfor_fndecl_caf_unlock, 6,
-				 token, integer_zero_node, integer_one_node,
+				 token, size_zero_node, integer_one_node,
 				 null_pointer_node, null_pointer_node,
-				 integer_zero_node);
+				 size_zero_node);
       gfc_add_expr_to_block (&block, tmp);
 
       /* It guarantees memory consistency within the same segment */
@@ -6774,7 +6774,7 @@ gfc_trans_allocate (gfc_code * code)
       /* Add a sync all after the allocation has been executed.  */
       tmp = build_call_expr_loc (input_location, gfor_fndecl_caf_sync_all,
 				 3, null_pointer_node, null_pointer_node,
-				 integer_zero_node);
+				 size_zero_node);
       gfc_add_expr_to_block (&post, tmp);
     }