Merge from trunk revision 104c05c5284b7822d770ee51a7d91946c7e56d50.

7 files changed, 211 insertions, 74 deletions

diff --git a/gcc/objc/ChangeLog b/gcc/objc/ChangeLog
index 6bb584c..668be66 100644
--- a/gcc/objc/ChangeLog
+++ b/gcc/objc/ChangeLog
@@ -1,3 +1,88 @@
+2021-09-01  Iain Sandoe  <iain@sandoe.co.uk>
+
+	PR objc/101718
+	* objc-next-runtime-abi-02.c (build_v2_build_objc_method_call):
+	Revise for cases where scalar objects use an sret parameter.
+	(next_runtime_abi_02_build_objc_method_call): Likwise.
+
+2021-09-01  Iain Sandoe  <iain@sandoe.co.uk>
+
+	* objc-act.c (objc_add_property_declaration): Register unavailable
+	attribute.
+	(maybe_make_artificial_property_decl): Set available.
+	(objc_maybe_build_component_ref): Generalise to the method prototype
+	to count availability.
+	(objc_build_class_component_ref): Likewise.
+	(build_private_template): Likewise.
+	(objc_decl_method_attributes): Handle unavailable attribute.
+	(lookup_method_in_hash_lists): Amend comments.
+	(objc_finish_message_expr): Handle unavailability in addition to
+	deprecation.
+	(start_class): Likewise.
+	(finish_class): Likewise.
+	(lookup_protocol): Likewise.
+	(objc_declare_protocol): Likewise.
+	(start_protocol): Register unavailable attribute.
+	(really_start_method): Likewise.
+	(objc_gimplify_property_ref): Emit error on encountering an
+	unavailable entity (and a warning for a deprecated one).
+
+2021-08-19  Iain Sandoe  <iain@sandoe.co.uk>
+
+	* objc-next-runtime-abi-02.c (objc_next_runtime_abi_02_init):
+	Default receiver nilchecks on.
+
+2021-08-18  Iain Sandoe  <iain@sandoe.co.uk>
+	    Matt Jacobson   <mhjacobson@me.com>
+
+	PR objc/101666
+	* objc-act.c (objc_build_constructor): Handle empty constructor
+	lists.
+	* objc-next-runtime-abi-02.c (build_v2_objc_method_fixup_call):
+	Handle nil receivers.
+	(build_v2_build_objc_method_call): Likewise.
+
+2021-08-17  Matt Jacobson  <mhjacobson@me.com>
+
+	* objc-next-runtime-abi-02.c
+	(objc_next_runtime_abi_02_init): Warn about and reset
+	flag_objc_sjlj_exceptions regardless of flag_objc_exceptions.
+	(next_runtime_02_initialize): Use a checking assert that
+	flag_objc_sjlj_exceptions is off.
+
+2021-06-28  Martin Sebor  <msebor@redhat.com>
+
+	* objc-act.c (objc_maybe_build_modify_expr): Replace direct uses
+	of TREE_NO_WARNING with warning_suppressed_p, and suppress_warning.
+	(objc_build_incr_expr_for_property_ref): Same.
+	(objc_build_struct): Same.
+	(synth_module_prologue): Same.
+	* objc-gnu-runtime-abi-01.c (gnu_runtime_01_initialize): Same.
+	* objc-next-runtime-abi-01.c (next_runtime_01_initialize): Same.
+	* objc-next-runtime-abi-02.c (next_runtime_02_initialize): Same.
+
+2021-06-08  Bernd Edlinger  <bernd.edlinger@hotmail.de>
+
+	* Make-lang.in (cc1-obj-checksum.c): Check previous
+	stage checksum exists.
+
+2021-06-07  Bernd Edlinger  <bernd.edlinger@hotmail.de>
+
+	* Make-lang.in (cc1obj-checksum.c): For stage-final re-use
+	the checksum from the previous stage.
+
+2021-05-20  Indu Bhagat  <indu.bhagat@oracle.com>
+
+	* objc-act.c (synth_module_prologue): Use uint32_t instead of enum
+	debug_info_type.
+
+2021-05-10  Martin Liska  <mliska@suse.cz>
+
+	* objc-act.c (objc_string_ref_type_p): Use startswith
+	function instead of strncmp.
+	* objc-encoding.c (encode_type): Likewise.
+	* objc-next-runtime-abi-02.c (has_load_impl): Likewise.
+
 2020-11-20  Jakub Jelinek  <jakub@redhat.com>
 
 	PR other/97911
diff --git a/gcc/objc/Make-lang.in b/gcc/objc/Make-lang.in
index c91148a..8215283 100644
--- a/gcc/objc/Make-lang.in
+++ b/gcc/objc/Make-lang.in
@@ -57,11 +57,20 @@ OBJC_OBJS = objc/objc-lang.o objc/objc-act.o hash-table.o \
 
 objc_OBJS = $(OBJC_OBJS) cc1obj-checksum.o
 
+# compute checksum over all object files and the options
+# re-use the checksum from the prev-final stage so it passes
+# the bootstrap comparison and allows comparing of the cc1 binary
 cc1obj-checksum.c : build/genchecksum$(build_exeext) checksum-options \
         $(OBJC_OBJS) $(C_AND_OBJC_OBJS) $(BACKEND) $(LIBDEPS)
-	build/genchecksum$(build_exeext) $(OBJC_OBJS) $(C_AND_OBJC_OBJS) \
-        $(BACKEND) $(LIBDEPS) checksum-options > cc1obj-checksum.c.tmp && \
-	$(srcdir)/../move-if-change cc1obj-checksum.c.tmp cc1obj-checksum.c
+	if [ -f ../stage_final ] \
+	   && cmp -s ../stage_current ../stage_final \
+	   && [ -f ../prev-gcc/$@ ]; then \
+	  cp ../prev-gcc/$@ $@; \
+	else \
+	  build/genchecksum$(build_exeext) $(OBJC_OBJS) $(C_AND_OBJC_OBJS) \
+		$(BACKEND) $(LIBDEPS) checksum-options > $@.tmp && \
+	  $(srcdir)/../move-if-change $@.tmp $@; \
+	fi
 
 cc1obj$(exeext): $(OBJC_OBJS) $(C_AND_OBJC_OBJS) cc1obj-checksum.o $(BACKEND) \
 		 $(LIBDEPS) $(objc.prev)
diff --git a/gcc/objc/objc-act.c b/gcc/objc/objc-act.c
index 1cbd586..9baa46d 100644
--- a/gcc/objc/objc-act.c
+++ b/gcc/objc/objc-act.c
@@ -1302,6 +1302,7 @@ objc_add_property_declaration (location_t location, tree decl,
   TREE_TYPE (property_decl) = p_type;
   DECL_SOURCE_LOCATION (property_decl) = DECL_SOURCE_LOCATION (decl);
   TREE_DEPRECATED (property_decl) = TREE_DEPRECATED (decl);
+  TREE_UNAVAILABLE (property_decl) = TREE_UNAVAILABLE (decl);
 
   /* Add property-specific information.  */
   PROPERTY_NAME (property_decl) = DECL_NAME (decl);
@@ -1439,6 +1440,7 @@ maybe_make_artificial_property_decl (tree interface, tree implementation,
       TREE_TYPE (property_decl) = type;
       DECL_SOURCE_LOCATION (property_decl) = input_location;
       TREE_DEPRECATED (property_decl) = 0;
+      TREE_UNAVAILABLE (property_decl) = 0;
       DECL_ARTIFICIAL (property_decl) = 1;
 
       /* Add property-specific information.  Note that one of
@@ -1717,7 +1719,7 @@ objc_maybe_build_component_ref (tree object, tree property_ident)
     {
       tree expression;
       tree getter_call;
-      tree deprecated_method_prototype = NULL_TREE;
+      tree method_prototype_avail = NULL_TREE;
 
       /* We have an additional nasty problem here; if this
 	 PROPERTY_REF needs to become a 'getter', then the conversion
@@ -1751,10 +1753,10 @@ objc_maybe_build_component_ref (tree object, tree property_ident)
 	      is deprecated, but record the fact that the getter is
 	      deprecated by setting PROPERTY_REF_DEPRECATED_GETTER to
 	      the method prototype.  */
-	   &deprecated_method_prototype);
+	   &method_prototype_avail);
 
       expression = build4 (PROPERTY_REF, TREE_TYPE(x), object, x, getter_call,
-			   deprecated_method_prototype);
+			   method_prototype_avail);
       SET_EXPR_LOCATION (expression, input_location);
       TREE_SIDE_EFFECTS (expression) = 1;
 
@@ -1804,7 +1806,9 @@ objc_build_class_component_ref (tree class_name, tree property_ident)
     }
   else
     {
-      if (TREE_DEPRECATED (rtype))
+      if (TREE_UNAVAILABLE (rtype))
+	error ("class %qE is unavailable", class_name);
+      else if (TREE_DEPRECATED (rtype))
 	warning (OPT_Wdeprecated_declarations, "class %qE is deprecated", class_name);
     }
 
@@ -1816,17 +1820,17 @@ objc_build_class_component_ref (tree class_name, tree property_ident)
     {
       tree expression;
       tree getter_call;
-      tree deprecated_method_prototype = NULL_TREE;
+      tree method_prototype_avail = NULL_TREE;
 
       if (PROPERTY_HAS_NO_GETTER (x))
 	getter_call = NULL_TREE;
       else
 	getter_call = objc_finish_message_expr
 	  (object, PROPERTY_GETTER_NAME (x), NULL_TREE,
-	   &deprecated_method_prototype);
+	   &method_prototype_avail);
 
       expression = build4 (PROPERTY_REF, TREE_TYPE(x), object, x, getter_call,
-			   deprecated_method_prototype);
+			   method_prototype_avail);
       SET_EXPR_LOCATION (expression, input_location);
       TREE_SIDE_EFFECTS (expression) = 1;
 
@@ -2007,7 +2011,7 @@ objc_maybe_build_modify_expr (tree lhs, tree rhs)
 	 correct (maybe a more sophisticated implementation could
 	 avoid generating the compound expression if not needed), but
 	 we need to turn it off.  */
-      TREE_NO_WARNING (compound_expr) = 1;
+      suppress_warning (compound_expr, OPT_Wunused);
       return compound_expr;
     }
   else
@@ -2129,7 +2133,7 @@ objc_build_incr_expr_for_property_ref (location_t location,
 
   /* Prevent C++ from warning with -Wall that "right operand of comma
      operator has no effect".  */
-  TREE_NO_WARNING (compound_expr) = 1;
+  suppress_warning (compound_expr, OPT_Wunused);
   return compound_expr;
 }
 
@@ -2262,8 +2266,9 @@ objc_build_struct (tree klass, tree fields, tree super_name)
       DECL_FIELD_IS_BASE (base) = 1;
 
       if (fields)
-	TREE_NO_WARNING (fields) = 1;	/* Suppress C++ ABI warnings -- we   */
-#endif					/* are following the ObjC ABI here.  */
+	/* Suppress C++ ABI warnings: we are following the ObjC ABI here.  */
+	suppress_warning (fields, OPT_Wabi);
+#endif
       DECL_CHAIN (base) = fields;
       fields = base;
     }
@@ -3078,7 +3083,7 @@ static void
 synth_module_prologue (void)
 {
   tree type;
-  enum debug_info_type save_write_symbols = write_symbols;
+  uint32_t save_write_symbols = write_symbols;
   const struct gcc_debug_hooks *const save_hooks = debug_hooks;
 
   /* Suppress outputting debug symbols, because
@@ -3112,19 +3117,19 @@ synth_module_prologue (void)
 						TYPE_DECL,
 						objc_object_name,
 						objc_object_type));
-  TREE_NO_WARNING (type) = 1;
+  suppress_warning (type);
 
   type = lang_hooks.decls.pushdecl (build_decl (input_location,
 						TYPE_DECL,
 						objc_instancetype_name,
 						objc_instancetype_type));
-  TREE_NO_WARNING (type) = 1;
+  suppress_warning (type);
 
   type = lang_hooks.decls.pushdecl (build_decl (input_location,
 						TYPE_DECL,
 						objc_class_name,
 						objc_class_type));
-  TREE_NO_WARNING (type) = 1;
+  suppress_warning (type);
 
   /* Forward-declare '@interface Protocol'.  */
   type = get_identifier (PROTOCOL_OBJECT_CLASS_NAME);
@@ -3376,8 +3381,10 @@ objc_build_string_object (tree string)
   return addr;
 }
 
-/* Build a static constant CONSTRUCTOR
-   with type TYPE and elements ELTS.  */
+/* Build a static constant CONSTRUCTOR with type TYPE and elements ELTS.
+   We might be presented with a NULL for ELTS, which means 'empty ctor'
+   which will subsequently be converted into a zero initializer in the
+   middle end.  */
 
 tree
 objc_build_constructor (tree type, vec<constructor_elt, va_gc> *elts)
@@ -3389,12 +3396,10 @@ objc_build_constructor (tree type, vec<constructor_elt, va_gc> *elts)
   TREE_READONLY (constructor) = 1;
 
 #ifdef OBJCPLUS
-  /* Adjust for impedance mismatch.  We should figure out how to build
-     CONSTRUCTORs that consistently please both the C and C++ gods.  */
-  if (!(*elts)[0].index)
+  /* If we know the initializer, then set the type to what C++ expects.  */
+  if (elts && !(*elts)[0].index)
     TREE_TYPE (constructor) = init_list_type_node;
 #endif
-
   return constructor;
 }
 
@@ -4597,6 +4602,8 @@ build_private_template (tree klass)
       /* Copy the attributes from the class to the type.  */
       if (TREE_DEPRECATED (klass))
 	TREE_DEPRECATED (record) = 1;
+      if (TREE_UNAVAILABLE (klass))
+	TREE_UNAVAILABLE (record) = 1;
     }
 }
 
@@ -5022,6 +5029,7 @@ objc_decl_method_attributes (tree *node, tree attributes, int flags)
 	  tree name = TREE_PURPOSE (attribute);
 
 	  if (is_attribute_p  ("deprecated", name)
+	      || is_attribute_p ("unavailable", name)
 	      || is_attribute_p ("sentinel", name)
 	      || is_attribute_p ("noreturn", name))
 	    {
@@ -5487,9 +5495,9 @@ lookup_method_in_hash_lists (tree sel_name, int is_class)
    C++ template functions, it is called from 'build_expr_from_tree'
    (in decl2.c) after RECEIVER and METHOD_PARAMS have been expanded.
 
-   If the DEPRECATED_METHOD_PROTOTYPE argument is NULL, then we warn
+   If the method_prototype_avail argument is NULL, then we warn
    if the method being used is deprecated.  If it is not NULL, instead
-   of deprecating, we set *DEPRECATED_METHOD_PROTOTYPE to the method
+   of deprecating, we set *method_prototype_avail to the method
    prototype that was used and is deprecated.  This is useful for
    getter calls that are always generated when compiling dot-syntax
    expressions, even if they may not be used.  In that case, we don't
@@ -5498,7 +5506,7 @@ lookup_method_in_hash_lists (tree sel_name, int is_class)
    used.  */
 tree
 objc_finish_message_expr (tree receiver, tree sel_name, tree method_params,
-			  tree *deprecated_method_prototype)
+			  tree *method_prototype_avail)
 {
   tree method_prototype = NULL_TREE, rprotos = NULL_TREE, rtype;
   tree retval, class_tree;
@@ -5810,10 +5818,17 @@ objc_finish_message_expr (tree receiver, tree sel_name, tree method_params,
 	 In practice this makes sense since casting an object to 'id'
 	 is often used precisely to turn off warnings associated with
 	 the object being of a particular class.  */
-      if (TREE_DEPRECATED (method_prototype) && rtype != NULL_TREE)
+      if (TREE_UNAVAILABLE (method_prototype) && rtype != NULL_TREE)
+	{
+	  if (method_prototype_avail)
+	    *method_prototype_avail = method_prototype;
+	  else
+	    error_unavailable_use (method_prototype, NULL_TREE);
+	}
+      else if (TREE_DEPRECATED (method_prototype) && rtype != NULL_TREE)
 	{
-	  if (deprecated_method_prototype)
-	    *deprecated_method_prototype = method_prototype;
+	  if (method_prototype_avail)
+	    *method_prototype_avail = method_prototype;
 	  else
 	    warn_deprecated_use (method_prototype, NULL_TREE);
 	}
@@ -6985,7 +7000,9 @@ start_class (enum tree_code code, tree class_name, tree super_name,
 	}
       else
 	{
-	  if (TREE_DEPRECATED (super_interface))
+	  if (TREE_UNAVAILABLE (super_interface))
+	    error ("class %qE is not available", super);
+	  else if (TREE_DEPRECATED (super_interface))
 	    warning (OPT_Wdeprecated_declarations, "class %qE is deprecated",
 		     super);
 	  super_name = super;
@@ -7095,7 +7112,9 @@ start_class (enum tree_code code, tree class_name, tree super_name,
 	      /* TODO: Document what the objc_exception attribute is/does.  */
 	      /* We handle the 'deprecated', 'visibility' and (undocumented)
 		 'objc_exception' attributes.  */
-	      if (is_attribute_p  ("deprecated", name))
+	      if (is_attribute_p  ("unavailable", name))
+		TREE_UNAVAILABLE (klass) = 1;
+	      else if (is_attribute_p  ("deprecated", name))
 		TREE_DEPRECATED (klass) = 1;
 	      else if (is_attribute_p  ("objc_exception", name))
 		CLASS_HAS_EXCEPTION_ATTR (klass) = 1;
@@ -7126,7 +7145,9 @@ start_class (enum tree_code code, tree class_name, tree super_name,
 	  }
 	else
 	  {
-	    if (TREE_DEPRECATED (class_category_is_assoc_with))
+	    if (TREE_UNAVAILABLE (class_category_is_assoc_with))
+	      error ("class %qE is unavailable", class_name);
+	    else if (TREE_DEPRECATED (class_category_is_assoc_with))
 	      warning (OPT_Wdeprecated_declarations, "class %qE is deprecated",
 		       class_name);
 
@@ -8153,6 +8174,7 @@ finish_class (tree klass)
 		else
 		  objc_add_method (objc_interface_context, getter_decl, false, false);
 		TREE_DEPRECATED (getter_decl) = TREE_DEPRECATED (x);
+		TREE_UNAVAILABLE (getter_decl) = TREE_UNAVAILABLE (x);
 		METHOD_PROPERTY_CONTEXT (getter_decl) = x;
 	      }
 
@@ -8197,6 +8219,7 @@ finish_class (tree klass)
 		    else
 		      objc_add_method (objc_interface_context, setter_decl, false, false);
 		    TREE_DEPRECATED (setter_decl) = TREE_DEPRECATED (x);
+		    TREE_UNAVAILABLE (setter_decl) = TREE_UNAVAILABLE (x);
 		    METHOD_PROPERTY_CONTEXT (setter_decl) = x;
 		  }
 	      }
@@ -8250,7 +8273,9 @@ lookup_protocol (tree ident, bool warn_if_deprecated, bool definition_required)
   for (chain = protocol_chain; chain; chain = TREE_CHAIN (chain))
     if (ident == PROTOCOL_NAME (chain))
       {
-	if (warn_if_deprecated && TREE_DEPRECATED (chain))
+	if (TREE_UNAVAILABLE (chain))
+	  error ("protocol %qE is unavailable", PROTOCOL_NAME (chain));
+	else if (warn_if_deprecated && TREE_DEPRECATED (chain))
 	  {
 	    /* It would be nice to use warn_deprecated_use() here, but
 	       we are using TREE_CHAIN (which is supposed to be the
@@ -8275,6 +8300,7 @@ void
 objc_declare_protocol (tree name, tree attributes)
 {
   bool deprecated = false;
+  bool unavailable = false;
 
 #ifdef OBJCPLUS
   if (current_namespace != global_namespace) {
@@ -8293,6 +8319,8 @@ objc_declare_protocol (tree name, tree attributes)
 
 	  if (is_attribute_p  ("deprecated", name))
 	    deprecated = true;
+	  else if (is_attribute_p  ("unavailable", name))
+	    unavailable = true;
 	  else
 	    warning (OPT_Wattributes, "%qE attribute directive ignored", name);
 	}
@@ -8317,6 +8345,8 @@ objc_declare_protocol (tree name, tree attributes)
 	  TYPE_ATTRIBUTES (protocol) = attributes;
 	  if (deprecated)
 	    TREE_DEPRECATED (protocol) = 1;
+	  if (unavailable)
+	    TREE_UNAVAILABLE (protocol) = 1;
 	}
     }
 }
@@ -8326,6 +8356,7 @@ start_protocol (enum tree_code code, tree name, tree list, tree attributes)
 {
   tree protocol;
   bool deprecated = false;
+  bool unavailable = false;
 
 #ifdef OBJCPLUS
   if (current_namespace != global_namespace) {
@@ -8344,6 +8375,8 @@ start_protocol (enum tree_code code, tree name, tree list, tree attributes)
 
 	  if (is_attribute_p  ("deprecated", name))
 	    deprecated = true;
+	  else if (is_attribute_p  ("unavailable", name))
+	    unavailable = true;
 	  else
 	    warning (OPT_Wattributes, "%qE attribute directive ignored", name);
 	}
@@ -8383,6 +8416,8 @@ start_protocol (enum tree_code code, tree name, tree list, tree attributes)
       TYPE_ATTRIBUTES (protocol) = attributes;
       if (deprecated)
 	TREE_DEPRECATED (protocol) = 1;
+      if (unavailable)
+	TREE_UNAVAILABLE (protocol) = 1;
     }
 
   return protocol;
@@ -8912,6 +8947,8 @@ really_start_method (tree method,
 		 warnings are produced), but just in case.  */
 	      if (TREE_DEPRECATED (proto))
 		TREE_DEPRECATED (method) = 1;
+	      if (TREE_UNAVAILABLE (proto))
+		TREE_UNAVAILABLE (method) = 1;
 
 	      /* If the method in the @interface was marked as
 		 'noreturn', mark the function implementing the method
@@ -9643,12 +9680,17 @@ objc_gimplify_property_ref (tree *expr_p)
       return;
     }
 
+  /* FIXME, this should be a label indicating availability in general.  */
   if (PROPERTY_REF_DEPRECATED_GETTER (*expr_p))
     {
-      /* PROPERTY_REF_DEPRECATED_GETTER contains the method prototype
+      if (TREE_UNAVAILABLE (PROPERTY_REF_DEPRECATED_GETTER (*expr_p)))
+	error_unavailable_use (PROPERTY_REF_DEPRECATED_GETTER (*expr_p),
+			       NULL_TREE);
+      else
+	/* PROPERTY_REF_DEPRECATED_GETTER contains the method prototype
 	 that is deprecated.  */
-      warn_deprecated_use (PROPERTY_REF_DEPRECATED_GETTER (*expr_p),
-			   NULL_TREE);
+	warn_deprecated_use (PROPERTY_REF_DEPRECATED_GETTER (*expr_p),
+			     NULL_TREE);
     }
 
   call_exp = getter;
@@ -9663,7 +9705,9 @@ objc_gimplify_property_ref (tree *expr_p)
       call_exp = TREE_OPERAND (getter, 1);
     }
 #endif
-  gcc_assert (TREE_CODE (call_exp) == CALL_EXPR);
+  gcc_checking_assert ((flag_objc_nilcheck
+			&& TREE_CODE (call_exp) == COND_EXPR)
+		       || TREE_CODE (call_exp) == CALL_EXPR);
 
   *expr_p = call_exp;
 }
@@ -10275,7 +10319,7 @@ objc_string_ref_type_p (tree strp)
   return (tmv
 	  && TREE_CODE (tmv) == IDENTIFIER_NODE
 	  && IDENTIFIER_POINTER (tmv)
-	  && !strncmp (IDENTIFIER_POINTER (tmv), "NSString", 8));
+	  && startswith (IDENTIFIER_POINTER (tmv), "NSString"));
 }
 
 /* At present the behavior of this is undefined and it does nothing.  */
diff --git a/gcc/objc/objc-encoding.c b/gcc/objc/objc-encoding.c
index c4067b1..7ad920a 100644
--- a/gcc/objc/objc-encoding.c
+++ b/gcc/objc/objc-encoding.c
@@ -733,7 +733,7 @@ encode_type (tree type, int curtype, int format)
 	  char *enc = (char *) obstack_base (&util_obstack) + curtype;
 
 	  /* Rewrite "in const" from "nr" to "rn".  */
-	  if (curtype >= 1 && !strncmp (enc - 1, "nr", 2))
+	  if (curtype >= 1 && startswith (enc - 1, "nr"))
 	    memcpy (enc - 1, "rn", 2);
 	}
     }
diff --git a/gcc/objc/objc-gnu-runtime-abi-01.c b/gcc/objc/objc-gnu-runtime-abi-01.c
index 4add71e..976fa1e 100644
--- a/gcc/objc/objc-gnu-runtime-abi-01.c
+++ b/gcc/objc/objc-gnu-runtime-abi-01.c
@@ -213,7 +213,7 @@ static void gnu_runtime_01_initialize (void)
 						TYPE_DECL,
 						objc_selector_name,
 						objc_selector_type));
-  TREE_NO_WARNING (type) = 1;
+  suppress_warning (type);
 
   /* typedef id (*IMP)(id, SEL, ...); */
   ftype = build_varargs_function_type_list (objc_object_type,
diff --git a/gcc/objc/objc-next-runtime-abi-01.c b/gcc/objc/objc-next-runtime-abi-01.c
index 3ec6e17..183fc01 100644
--- a/gcc/objc/objc-next-runtime-abi-01.c
+++ b/gcc/objc/objc-next-runtime-abi-01.c
@@ -282,7 +282,7 @@ static void next_runtime_01_initialize (void)
 						TYPE_DECL,
 						objc_selector_name,
 						objc_selector_type));
-  TREE_NO_WARNING (type) = 1;
+  suppress_warning (type);
 
   build_v1_class_template ();
   build_super_template ();
diff --git a/gcc/objc/objc-next-runtime-abi-02.c b/gcc/objc/objc-next-runtime-abi-02.c
index af68c1c..9c35738 100644
--- a/gcc/objc/objc-next-runtime-abi-02.c
+++ b/gcc/objc/objc-next-runtime-abi-02.c
@@ -245,7 +245,7 @@ objc_next_runtime_abi_02_init (objc_runtime_hooks *rthooks)
 {
   extern_names = ggc_cleared_vec_alloc<hash> (SIZEHASHTABLE);
 
-  if (flag_objc_exceptions && flag_objc_sjlj_exceptions)
+  if (flag_objc_sjlj_exceptions)
     {
       inform (UNKNOWN_LOCATION,
 	      "%<-fobjc-sjlj-exceptions%> is ignored for "
@@ -254,6 +254,10 @@ objc_next_runtime_abi_02_init (objc_runtime_hooks *rthooks)
       flag_objc_sjlj_exceptions = 0;
     }
 
+  /* NeXT ABI 2 is intended to default to checking for nil receivers.  */
+  if (! global_options_set.x_flag_objc_nilcheck)
+    flag_objc_nilcheck = 1;
+
   rthooks->initialize = next_runtime_02_initialize;
   rthooks->default_constant_string_class_name = DEF_CONSTANT_STRING_CLASS_NAME;
   rthooks->tag_getclass = TAG_GETCLASS;
@@ -379,7 +383,7 @@ static void next_runtime_02_initialize (void)
 						TYPE_DECL,
 						objc_selector_name,
 						objc_selector_type));
-  TREE_NO_WARNING (type) = 1;
+  suppress_warning (type);
 
   /* IMP : id (*) (id, _message_ref_t*, ...)
      SUPER_IMP : id (*) ( super_t*, _super_message_ref_t*, ...)
@@ -507,7 +511,7 @@ static void next_runtime_02_initialize (void)
   objc_getPropertyStruct_decl = NULL_TREE;
   objc_setPropertyStruct_decl = NULL_TREE;
 
-  gcc_assert (!flag_objc_sjlj_exceptions);
+  gcc_checking_assert (!flag_objc_sjlj_exceptions);
 
   /* Although we warn that fobjc-exceptions is required for exceptions
      code, we carry on and create it anyway.  */
@@ -1675,13 +1679,8 @@ build_v2_objc_method_fixup_call (int super_flag, tree method_prototype,
 
       if (TREE_CODE (ret_type) == RECORD_TYPE
 	  || TREE_CODE (ret_type) == UNION_TYPE)
-	{
-	  vec<constructor_elt, va_gc> *rtt = NULL;
-	  /* ??? CHECKME. hmmm..... think we need something more
-	     here.  */
-	  CONSTRUCTOR_APPEND_ELT (rtt, NULL_TREE, NULL_TREE);
-	  ftree = objc_build_constructor (ret_type, rtt);
-	}
+	/* An empty constructor is zero-filled by the middle end.  */
+	ftree = objc_build_constructor (ret_type, NULL);
       else
 	ftree = fold_convert (ret_type, integer_zero_node);
 
@@ -1694,11 +1693,11 @@ build_v2_objc_method_fixup_call (int super_flag, tree method_prototype,
 					ifexp, ret_val, ftree,
 					tf_warning_or_error);
 #else
-     /* ??? CHECKME.   */
       ret_val = build_conditional_expr (input_location,
-					ifexp, 1,
+					ifexp, 0,
 					ret_val, NULL_TREE, input_location,
 					ftree, NULL_TREE, input_location);
+      ret_val = fold_convert (ret_type, ret_val);
 #endif
     }
   return ret_val;
@@ -1740,15 +1739,16 @@ build_v2_build_objc_method_call (int super, tree method_prototype,
   /* Param list + 2 slots for object and selector.  */
   vec_alloc (parms, nparm + 2);
 
-  /* If we are returning a struct in memory, and the address
-     of that memory location is passed as a hidden first
-     argument, then change which messenger entry point this
-     expr will call.  NB: Note that sender_cast remains
-     unchanged (it already has a struct return type).  */
-  if (!targetm.calls.struct_value_rtx (0, 0)
-      && (TREE_CODE (ret_type) == RECORD_TYPE
-	  || TREE_CODE (ret_type) == UNION_TYPE)
-      && targetm.calls.return_in_memory (ret_type, 0))
+  /* If we are returning an item that must be returned in memory, and the
+     target ABI does this by an invisible pointer provided as the first arg,
+     we need to adjust the message signature to include this.  The second
+     part of this excludes targets that provide some alternate scheme for
+     structure returns.  */
+  if (ret_type && !VOID_TYPE_P (ret_type)
+      && targetm.calls.return_in_memory (ret_type, 0)
+      && !(targetm.calls.struct_value_rtx (0, 0)
+	   && (TREE_CODE (ret_type) == RECORD_TYPE
+	       || TREE_CODE (ret_type) == UNION_TYPE)))
     {
       if (super)
 	sender = umsg_id_super2_stret_fixup_decl;
@@ -1790,11 +1790,8 @@ build_v2_build_objc_method_call (int super, tree method_prototype,
       if (TREE_CODE (ret_type) == RECORD_TYPE
 	  || TREE_CODE (ret_type) == UNION_TYPE)
 	{
-	  vec<constructor_elt, va_gc> *rtt = NULL;
-	  /* ??? CHECKME. hmmm..... think we need something more
-	     here.  */
-	  CONSTRUCTOR_APPEND_ELT (rtt, NULL_TREE, NULL_TREE);
-	  ftree = objc_build_constructor (ret_type, rtt);
+	/* An empty constructor is zero-filled by the middle end.  */
+	  ftree = objc_build_constructor (ret_type, NULL);
 	}
       else
 	ftree = fold_convert (ret_type, integer_zero_node);
@@ -1807,10 +1804,10 @@ build_v2_build_objc_method_call (int super, tree method_prototype,
       ret_val = build_conditional_expr (loc, ifexp, ret_val, ftree,
 					tf_warning_or_error);
 #else
-     /* ??? CHECKME.   */
       ret_val = build_conditional_expr (loc, ifexp, 1,
 					ret_val, NULL_TREE, loc,
 					ftree, NULL_TREE, loc);
+      ret_val = fold_convert (ret_type, ret_val);
 #endif
     }
   return ret_val;
@@ -1853,10 +1850,12 @@ next_runtime_abi_02_build_objc_method_call (location_t loc,
 	     ? TREE_VALUE (TREE_TYPE (method_prototype))
 	     : objc_object_type;
 
-  if (!targetm.calls.struct_value_rtx (0, 0)
-      && (TREE_CODE (ret_type) == RECORD_TYPE
-	  || TREE_CODE (ret_type) == UNION_TYPE)
-      && targetm.calls.return_in_memory (ret_type, 0))
+  /* See comment for the fixup version above.  */
+  if (ret_type && !VOID_TYPE_P (ret_type)
+      && targetm.calls.return_in_memory (ret_type, 0)
+      && !(targetm.calls.struct_value_rtx (0, 0)
+	   && (TREE_CODE (ret_type) == RECORD_TYPE
+	       || TREE_CODE (ret_type) == UNION_TYPE)))
     {
       if (super)
 	message_func_decl = umsg_id_super2_stret_fixup_decl;
@@ -2209,7 +2208,7 @@ has_load_impl (tree clsmeth)
     {
       tree id = METHOD_SEL_NAME (clsmeth);
       if (IDENTIFIER_LENGTH (id) == 4
-	  && strncmp (IDENTIFIER_POINTER (id), "load", 4) == 0)
+	  && startswith (IDENTIFIER_POINTER (id), "load"))
         return true;
       clsmeth = DECL_CHAIN (clsmeth);
     }