gcc: Add support for Apple's Block extension

Block objects [1] are a C-level syntactic and runtime feature. They
are similar to standard C functions, but in addition to executable
code they may also contain variable bindings to automatic (stack)
or managed (heap) memory. A block can therefore maintain a set of
state (data) that it can use to impact behavior when executed.

This port is based on Apple's GCC 5646 with some bugfixes from
Apple GCC 5666.3. It has some small differences with the support
in clang, which remains the recommended compiler.

Perhaps the most notable difference is that in GCC that __block
is not actually a keyword, but a macro. There will be workaround
for this issue in a near future. Other issues can be consulted in
the clang documentation [2]

For better compatiblity with Apple's GCC and llvm-gcc some related
fixes and features from Apple have been included. Support for the
non-standard nested functions in GCC is now off by default.

No effort was made to update the ObjC support since FreeBSD doesn't
carry ObjC in the base system, but some of the code crept in and
was more difficult to remove than to adjust.

Reference:
[1]
https://developer.apple.com/library/mac/documentation/Cocoa/Conceptual/Blocks/Articles/00_Introduction.html
[2]
http://clang.llvm.org/compatibility.html#block-variable-initialization

Obtained from:	Apple GCC 4.2
MFC after:	3 weeks

1 files changed, 575 insertions, 8 deletions

diff --git a/contrib/gcc/cp/decl.c b/contrib/gcc/cp/decl.c
index 40e6c92..e7cb972 100644
--- a/contrib/gcc/cp/decl.c
+++ b/contrib/gcc/cp/decl.c
@@ -52,7 +52,8 @@ Boston, MA 02110-1301, USA.  */
 #include "timevar.h"
 #include "tree-flow.h"
 
-static tree grokparms (cp_parameter_declarator *, tree *);
+/* APPLE LOCAL blocks 6040305 (ce) */
+tree grokparms (cp_parameter_declarator *, tree *);
 static const char *redeclaration_error_message (tree, tree);
 
 static int decl_jump_unsafe (tree);
@@ -3800,7 +3801,26 @@ shadow_tag (cp_decl_specifier_seq *declspecs)
 
   return t;
 }
-
+
+/* APPLE LOCAL begin blocks 6339747 */
+/* Decode a block literal type, such as "int **", returning a ...FUNCTION_DECL node.  */
+
+tree
+grokblockdecl (cp_decl_specifier_seq *type_specifiers,
+	   const cp_declarator *declarator)
+{
+  tree decl;
+  tree attrs = type_specifiers->attributes;
+  
+  type_specifiers->attributes = NULL_TREE;
+  
+  decl = grokdeclarator (declarator, type_specifiers, BLOCKDEF, 0, &attrs);
+  if (attrs)
+      cplus_decl_attributes (&decl, attrs, 0);
+  return decl;
+}
+/* APPLE LOCAL end blocks 6339747 */
+
 /* Decode a "typename", such as "int **", returning a ..._TYPE node.  */
 
 tree
@@ -5002,10 +5022,15 @@ make_rtl_for_nonlocal_decl (tree decl, tree init, const char* asmspec)
   if (DECL_LANG_SPECIFIC (decl) && DECL_IN_AGGR_P (decl))
     {
       gcc_assert (TREE_STATIC (decl));
+      /* APPLE LOCAL begin templated static data 6298605 */
       /* An in-class declaration of a static data member should be
-	 external; it is only a declaration, and not a definition. */
-      if (init == NULL_TREE && DECL_INITIAL (decl) == NULL_TREE)
+	 external if the decl is accessible from outside this
+	 translation unit (eg something not in an anonymous
+	 namespace); it is only a declaration, and not a
+	 definition.  */
+      if (init == NULL_TREE && TREE_PUBLIC (decl))
 	gcc_assert (DECL_EXTERNAL (decl));
+      /* APPLE LOCAL end templated static data 6298605 */
     }
 
   /* We don't create any RTL for local variables.  */
@@ -5160,6 +5185,367 @@ value_dependent_init_p (tree init)
   return false;
 }
 
+/* APPLE LOCAL begin blocks 6040305 (cr) */
+#define BLOCK_ALIGN_MAX 18
+static tree block_byref_id_object_copy[BLOCK_BYREF_CURRENT_MAX*(BLOCK_ALIGN_MAX+1)];
+static tree block_byref_id_object_dispose[BLOCK_BYREF_CURRENT_MAX*(BLOCK_ALIGN_MAX+1)];
+
+/**
+ This routine builds:
+
+ void __Block_byref_id_object_copy(struct Block_byref_id_object *dst,
+				   struct Block_byref_id_object *src) {
+   _Block_object_assign (&_dest->object, _src->object, BLOCK_FIELD_IS_OBJECT[|BLOCK_FIELD_IS_WEAK]) // objects
+   _Block_object_assign(&_dest->object, _src->object, BLOCK_FIELD_IS_BLOCK[|BLOCK_FIELD_IS_WEAK])  //  blocks
+ }  */
+static void
+synth_block_byref_id_object_copy_func (int flag, int kind)
+{
+  tree stmt;
+  tree dst_arg, src_arg;
+  tree dst_obj, src_obj;
+  tree call_exp;
+
+  gcc_assert (block_byref_id_object_copy[kind]);
+  /* Set up: (void* _dest, void*_src) parameters. */
+  dst_arg = build_decl (PARM_DECL, get_identifier ("_dst"),
+			 ptr_type_node);
+  TREE_USED (dst_arg) = 1;
+  DECL_ARG_TYPE (dst_arg) = ptr_type_node;
+  src_arg = build_decl (PARM_DECL, get_identifier ("_src"),
+			 ptr_type_node);
+  TREE_USED (src_arg) = 1;
+  DECL_ARG_TYPE (src_arg) = ptr_type_node;
+  /* arg_info = xcalloc (1, sizeof (struct c_arg_info)); */
+  TREE_CHAIN (dst_arg) = src_arg;
+  /* arg_info->parms = dst_arg; */
+  /* arg_info->types = tree_cons (NULL_TREE, ptr_type_node,
+				   tree_cons (NULL_TREE,
+				   ptr_type_node,
+				   NULL_TREE)); */
+  DECL_ARGUMENTS (block_byref_id_object_copy[kind]) = dst_arg;
+  /* function header synthesis. */
+  push_function_context ();
+  /* start_block_helper_function (block_byref_id_object_copy[kind], true); */
+  /* store_parm_decls_from (arg_info); */
+  start_preparsed_function (block_byref_id_object_copy[kind],
+			     /*attrs*/NULL_TREE,
+			     SF_PRE_PARSED);
+
+  /* Body of the function. */
+  stmt = begin_compound_stmt (BCS_FN_BODY);
+  /* Build dst->object */
+  dst_obj = build_indirect_object_id_exp (dst_arg);
+
+
+  /* src_obj is: _src->object. */
+  src_obj = build_indirect_object_id_exp (src_arg);
+  /* APPLE LOCAL begin radar 6180456 */
+  /* _Block_object_assign (&_dest->object, _src->object, BLOCK_FIELD_IS_OBJECT) or:
+     _Block_object_assign (&_dest->object, _src->object, BLOCK_FIELD_IS_BLOCK) */
+  /* APPLE LOCAL begin radar 6573923 */
+  /* Also add the new flag when calling _Block_object_dispose
+     from byref dispose helper. */
+  flag |= BLOCK_BYREF_CALLER;
+ /* APPLE LOCAL end radar 6573923 */
+  call_exp = build_block_object_assign_call_exp (build_fold_addr_expr (dst_obj), src_obj, flag);
+  add_stmt (call_exp);
+  /* APPLE LOCAL end radar 6180456 */
+
+  finish_compound_stmt (stmt);
+  /* APPLE LOCAL radar 6169580 */
+  finish_function (4);
+  pop_function_context ();
+}
+
+/**
+  This routine builds:
+
+  void __Block_byref_id_object_dispose(struct Block_byref_id_object *_src) {
+    _Block_object_dispose(_src->object, BLOCK_FIELD_IS_OBJECT[|BLOCK_FIELD_IS_WEAK]) // objects
+    _Block_object_dispose(_src->object, BLOCK_FIELD_IS_BLOCK[|BLOCK_FIELD_IS_WEAK]) // blocks
+  }  */
+static void synth_block_byref_id_object_dispose_func (int flag, int kind)
+{
+  tree stmt;
+  tree src_arg, src_obj, rel_exp;
+
+  gcc_assert (block_byref_id_object_dispose[kind]);
+  /* Set up: (void *_src) parameter. */
+  src_arg = build_decl (PARM_DECL, get_identifier ("_src"),
+			 ptr_type_node);
+  TREE_USED (src_arg) = 1;
+  DECL_ARG_TYPE (src_arg) = ptr_type_node;
+  /* arg_info = xcalloc (1, sizeof (struct c_arg_info));
+     arg_info->parms = src_arg;
+     arg_info->types = tree_cons (NULL_TREE, ptr_type_node,
+			           NULL_TREE); */
+  DECL_ARGUMENTS (block_byref_id_object_dispose[kind]) = src_arg;
+  /* function header synthesis. */
+  push_function_context ();
+  /* start_block_helper_function (block_byref_id_object_dispose[kind], true); */
+  /* store_parm_decls_from (arg_info); */
+  start_preparsed_function (block_byref_id_object_dispose[kind],
+			     /*attrs*/NULL_TREE,
+			     SF_PRE_PARSED);
+
+  /* Body of the function. */
+  stmt = begin_compound_stmt (BCS_FN_BODY);
+  src_obj = build_indirect_object_id_exp (src_arg);
+
+  /* APPLE LOCAL begin radar 6180456 */
+  /* _Block_object_dispose(_src->object, BLOCK_FIELD_IS_OBJECT) or:
+     _Block_object_dispose(_src->object, BLOCK_FIELD_IS_BLOCK) */
+  /* APPLE LOCAL begin radar 6573923 */
+  /* Also add the new flag when calling _Block_object_dispose
+     from byref dispose helper. */
+  flag |= BLOCK_BYREF_CALLER;
+ /* APPLE LOCAL end radar 6573923 */
+  rel_exp = build_block_object_dispose_call_exp (src_obj, flag);
+  /* APPLE LOCAL end radar 6180456 */
+  add_stmt (rel_exp);
+
+  finish_compound_stmt (stmt);
+  /* APPLE LOCAL radar 6169580 */
+  finish_function (4);
+  pop_function_context ();
+}
+
+static tree
+block_start_struct (tree name)
+{
+  tree s;
+  /* The idea here is to mimic the actions that the C++ parser takes when
+   constructing 'extern "C" struct NAME {'.  */
+  push_lang_context (lang_name_c);
+
+  s = xref_tag (record_type, name, ts_global, 0);
+  CLASSTYPE_DECLARED_CLASS (s) = 0;  /* this is a 'struct', not a 'class'.  */
+  xref_basetypes (s, NULL_TREE);     /* no base classes here!  */
+
+  return begin_class_definition (s, NULL_TREE);
+}
+
+static tree
+block_finish_struct (tree t, tree fieldlist)
+{
+  tree field, next_field;
+
+  for (field = fieldlist; field; field = next_field)
+  {
+    next_field = TREE_CHAIN (field);      /* insert one field at a time;  */
+    TREE_CHAIN (field) = NULL_TREE;       /* otherwise, grokfield croaks. */
+    finish_member_declaration (field);
+  }
+  t = finish_struct (t, NULL);
+  pop_lang_context ();
+
+  return t;
+}
+
+/* new_block_byref_decl - This routine changes a 'typex x' declared variable into:
+
+  struct __Block_byref_x {
+    // APPLE LOCAL radar 6244520
+    void *__isa;			// NULL for everything except __weak pointers
+    struct Block_byref_x *__forwarding;
+    int32_t __flags;
+    int32_t __size;
+    void *__ByrefKeepFuncPtr;    // Only if variable is __block ObjC object
+    void *__ByrefDestroyFuncPtr; // Only if variable is __block ObjC object
+    typex x;
+  } x;
+*/
+
+static tree
+new_block_byref_decl (tree decl)
+{
+  static int unique_count;
+  /* APPLE LOCAL radar 5847976 */
+  int save_flag_objc_gc;
+  tree Block_byref_type;
+  tree fields = NULL_TREE, field;
+  const char *prefix = "__Block_byref_";
+  char *string = (char*)alloca (strlen (IDENTIFIER_POINTER (DECL_NAME (decl))) +
+				strlen (prefix) + 8 /* to hold the count */);
+
+  sprintf (string, "%s%d_%s", prefix, ++unique_count,
+	    IDENTIFIER_POINTER (DECL_NAME (decl)));
+
+  push_to_top_level ();
+    
+  /* Block_byref_type = start_struct (RECORD_TYPE, get_identifier (string)); */
+  Block_byref_type = block_start_struct (get_identifier (string));
+  
+  /* APPLE LOCAL begin radar 6244520 */
+  /* void *__isa; */
+  field = build_decl (FIELD_DECL, get_identifier ("__isa"), ptr_type_node);
+  fields = field;
+  /* APPLE LOCAL end radar 6244520 */  
+
+  /* struct Block_byref_x *__forwarding; */
+  field = build_decl (FIELD_DECL, get_identifier ("__forwarding"),
+	               build_pointer_type (Block_byref_type));
+  /* APPLE LOCAL radar 6244520 */
+  chainon (fields, field);
+
+  /* int32_t __flags; */
+  field = build_decl (FIELD_DECL, get_identifier ("__flags"),
+	               unsigned_type_node);
+  chainon (fields, field);
+
+  /* int32_t __size; */
+  field = build_decl (FIELD_DECL, get_identifier ("__size"),
+	               unsigned_type_node);
+  chainon (fields, field);
+
+  if (COPYABLE_BYREF_LOCAL_NONPOD (decl))
+  {
+    /* void *__ByrefKeepFuncPtr; */
+    field = build_decl (FIELD_DECL, get_identifier ("__ByrefKeepFuncPtr"),
+			 ptr_type_node);
+    chainon (fields, field);
+
+    /* void *__ByrefDestroyFuncPtr; */
+    field = build_decl (FIELD_DECL, get_identifier ("__ByrefDestroyFuncPtr"),
+			 ptr_type_node);
+    chainon (fields, field);
+  }
+
+  /* typex x; */
+  field = build_decl (FIELD_DECL, DECL_NAME (decl), TREE_TYPE (decl));
+  chainon (fields, field);
+
+  /* APPLE LOCAL begin radar 5847976 */
+  /* Hack so we don't issue warning on a field_decl having __weak attribute */
+  save_flag_objc_gc = flag_objc_gc;
+  flag_objc_gc = 0;
+  /* finish_struct (Block_byref_type, field_decl_chain, NULL_TREE); */
+  block_finish_struct (Block_byref_type, fields);
+  flag_objc_gc = save_flag_objc_gc;
+  /* APPLE LOCAL end radar 5847976 */
+  pop_from_top_level ();
+
+  TREE_TYPE (decl) = Block_byref_type;
+  /* Force layout_decl to recompute these fields. */
+  DECL_SIZE (decl) = DECL_SIZE_UNIT (decl) = 0;
+  layout_decl (decl, 0);
+  return decl;
+}
+
+/* init_byref_decl - This routine builds the initializer for the __Block_byref_x
+   type in the form of:
+   { NULL, &x, 0, sizeof(struct __Block_byref_x), initializer-expr};
+
+   or:
+   { NULL, &x, 0, sizeof(struct __Block_byref_x)};
+   when INIT is NULL_TREE
+
+   For __block ObjC objects, it also adds "byref_keep" and "byref_destroy"
+   Funtion pointers. So the most general initializers would be:
+
+   { NULL, &x, 0, sizeof(struct __Block_byref_x), &byref_keep, &byref_destroy,
+     &initializer-expr};
+ */
+static tree
+init_byref_decl (tree decl, tree init, int flag)
+{
+  tree initlist;
+  tree block_byref_type = TREE_TYPE (decl);
+  int size = TREE_INT_CST_LOW (TYPE_SIZE_UNIT (block_byref_type));
+  unsigned flags = 0;
+  tree fields;
+
+  if (COPYABLE_BYREF_LOCAL_NONPOD (decl))
+    flags = BLOCK_HAS_COPY_DISPOSE;
+
+  fields = TYPE_FIELDS (block_byref_type);
+  /* APPLE LOCAL begin radar 6244520 */
+  initlist = tree_cons (fields, fold_convert (ptr_type_node, ((flag & BLOCK_FIELD_IS_WEAK) != 0) ? integer_one_node
+			                                                         : integer_zero_node), 
+			 0);
+  fields = TREE_CHAIN (fields);
+  
+  initlist = tree_cons (fields,
+			 build_unary_op (ADDR_EXPR, decl, 0), initlist);
+   /* APPLE LOCAL end radar 6244520 */
+  fields = TREE_CHAIN (fields);
+
+  initlist = tree_cons (fields, build_int_cst (TREE_TYPE (fields), flags),
+			 initlist);
+  fields = TREE_CHAIN (fields);
+  initlist = tree_cons (fields, build_int_cst (TREE_TYPE (fields), size),
+			 initlist);
+  fields = TREE_CHAIN (fields);
+
+  if (COPYABLE_BYREF_LOCAL_NONPOD (decl))
+    {
+      char name[64];
+      int align = exact_log2 ((DECL_ALIGN (decl)+TYPE_ALIGN (ptr_type_node)-1) / TYPE_ALIGN (ptr_type_node));
+      int kind;
+      if (align == -1 || align > BLOCK_ALIGN_MAX) {
+	error ("invalid alignment for __block variable");
+	kind = 0;
+      } else
+	kind = align*BLOCK_BYREF_CURRENT_MAX + flag;
+      /* Add &__Block_byref_id_object_copy, &__Block_byref_id_object_dispose
+	 initializers. */
+      if (!block_byref_id_object_copy[kind])
+	{
+	  tree func_type;
+	  push_lang_context (lang_name_c);
+	  /* Build a void __Block_byref_id_object_copy(void*, void*) type. */
+	  func_type =
+	    build_function_type (void_type_node,
+				 tree_cons (NULL_TREE, ptr_type_node,
+					    tree_cons (NULL_TREE, ptr_type_node,
+						       void_list_node)));
+	  sprintf (name, "__Block_byref_id_object_copy%d", kind);
+	  block_byref_id_object_copy[kind] = build_helper_func_decl (get_identifier (name),
+								     func_type);
+	  DECL_CONTEXT (block_byref_id_object_copy[kind]) = current_function_decl;
+	  /* Synthesize function definition. */
+	  synth_block_byref_id_object_copy_func (flag, kind);
+	  pop_lang_context ();
+	}
+      initlist = tree_cons (fields,
+			    build_fold_addr_expr (block_byref_id_object_copy[kind]),
+			    initlist);
+      fields = TREE_CHAIN (fields);
+
+      if (!block_byref_id_object_dispose[kind])
+	{
+	  tree func_type;
+	  push_lang_context (lang_name_c);
+	  /* Synthesize void __Block_byref_id_object_dispose (void*) and
+	     build &__Block_byref_id_object_dispose. */
+	  func_type =
+	    build_function_type (void_type_node,
+				 tree_cons (NULL_TREE, ptr_type_node, void_list_node));
+	  sprintf (name, "__Block_byref_id_object_dispose%d", kind);
+	  block_byref_id_object_dispose[kind] = build_helper_func_decl (get_identifier (name),
+									func_type);
+	  DECL_CONTEXT (block_byref_id_object_dispose[kind]) = current_function_decl;
+	  /* Synthesize function definition. */
+	  synth_block_byref_id_object_dispose_func (flag, kind);
+	  pop_lang_context ();
+	}
+      initlist = tree_cons (fields,
+			    build_fold_addr_expr (block_byref_id_object_dispose[kind]),
+			    initlist);
+      fields = TREE_CHAIN (fields);
+    }
+
+  if (init)
+    {
+      init = digest_init (TREE_TYPE (fields), init);
+      initlist = tree_cons (fields, init, initlist);
+    }
+  init =  build_constructor_from_list (block_byref_type, nreverse (initlist));
+  return init;
+}
+/* APPLE LOCAL end blocks 6040305 (cr) */
+
 /* Finish processing of a declaration;
    install its line number and initial value.
    If the length of an array type is not known before,
@@ -5295,6 +5681,17 @@ cp_finish_decl (tree decl, tree init, bool init_const_expr_p,
       if (DECL_THREAD_LOCAL_P (decl) && !pod_type_p (TREE_TYPE (decl)))
 	error ("%qD cannot be thread-local because it has non-POD type %qT",
 	       decl, TREE_TYPE (decl));
+      /* APPLE LOCAL begin blocks 6040305 (cq) */
+      if (COPYABLE_BYREF_LOCAL_VAR (decl)) {
+	 if (DECL_EXTERNAL (decl) || TREE_STATIC (decl))
+	  {
+	    error ("__block attribute on %q+D not allowed, only allowed on local variables", decl);
+	    COPYABLE_BYREF_LOCAL_VAR (decl) = 0;
+	    COPYABLE_BYREF_LOCAL_NONPOD (decl) = 0;
+	  }
+      }
+      /* APPLE LOCAL end blocks 6040305 (cq) */
+      
       /* If this is a local variable that will need a mangled name,
 	 register it now.  We must do this before processing the
 	 initializer for the variable, since the initialization might
@@ -5760,6 +6157,16 @@ expand_static_init (tree decl, tree init)
       && TYPE_HAS_TRIVIAL_DESTRUCTOR (TREE_TYPE (decl)))
     return;
 
+  /* APPLE LOCAL begin radar 5733674 */
+  if (c_dialect_objc () && flag_objc_gc && init && TREE_CODE (init) == INIT_EXPR)
+  {
+    tree result = objc_generate_write_barrier (TREE_OPERAND (init, 0),
+					        INIT_EXPR, TREE_OPERAND (init, 1));
+    if (result)
+      init = result;
+  }
+  /* APPLE LOCAL end radar 5733674 */
+  
   if (DECL_FUNCTION_SCOPE_P (decl))
     {
       /* Emit code to perform this initialization but once.  */
@@ -7235,6 +7642,8 @@ grokdeclarator (const cp_declarator *declarator,
 	  case cdk_pointer:
 	  case cdk_reference:
 	  case cdk_ptrmem:
+	    /* APPLE LOCAL blocks 6040305 */
+	  case cdk_block_pointer:
 	    break;
 
 	  case cdk_error:
@@ -7930,6 +8339,33 @@ grokdeclarator (const cp_declarator *declarator,
 	  ctype = NULL_TREE;
 	  break;
 
+	  /* APPLE LOCAL begin blocks 6040305 (cj) */
+	case cdk_block_pointer:
+	  if (TREE_CODE (type) != FUNCTION_TYPE)
+	    {
+	      error ("block pointer to non-function type is invalid");
+	      type = error_mark_node;
+	    }
+	  else
+	    {
+	      /* We now know that the TYPE_QUALS don't apply to the decl,
+		 but to the target of the pointer.  */
+	      type_quals = TYPE_UNQUALIFIED;
+
+	      type = build_block_pointer_type (type);
+
+	      if (declarator->u.pointer.qualifiers)
+		{
+		  type
+		    = cp_build_qualified_type (type,
+					       declarator->u.pointer.qualifiers);
+		  type_quals = cp_type_quals (type);
+		}
+	    }
+	  ctype = NULL_TREE;
+	  break;
+	  /* APPLE LOCAL end blocks 6040305 (cj) */
+
 	case cdk_error:
 	  break;
 
@@ -8121,6 +8557,38 @@ grokdeclarator (const cp_declarator *declarator,
 	}
     }
 
+  /* APPLE LOCAL begin blocks 6339747 */
+  if (decl_context == BLOCKDEF)
+    {
+      tree decl;
+
+      if (type == error_mark_node)
+	return error_mark_node;
+
+      if (TREE_CODE (type) != FUNCTION_TYPE)
+	{
+	  tree t = make_node (FUNCTION_TYPE);
+
+	  if (TREE_CODE (type) == ARRAY_TYPE)
+	    {
+	      error ("block declared as returning an array");
+	      return error_mark_node;
+	    }
+
+	  TYPE_ARG_TYPES (t) = void_list_node;
+	  TREE_TYPE (t) = type;
+	  type = t;
+	  parms = NULL_TREE;
+	}	    
+
+      if (raises)
+	type = build_exception_variant (type, raises);
+      decl = build_lang_decl (FUNCTION_DECL, NULL_TREE, type);
+      DECL_ARGUMENTS (decl) = parms;
+      return decl;
+    }
+  /* APPLE LOCAL end blocks 6339747 */
+
   /* If this is declaring a typedef name, return a TYPE_DECL.  */
   if (declspecs->specs[(int)ds_typedef] && decl_context != TYPENAME)
     {
@@ -8973,7 +9441,8 @@ check_default_argument (tree decl, tree arg)
 
    *PARMS is set to the chain of PARM_DECLs created.  */
 
-static tree
+/* APPLE LOCAL blocks 6040305 (ce) */
+tree
 grokparms (cp_parameter_declarator *first_parm, tree *parms)
 {
   tree result = NULL_TREE;
@@ -10909,6 +11378,82 @@ start_preparsed_function (tree decl1, tree attrs, int flags)
 }
 
 
+/* APPLE LOCAL begin warn missing prototype 6261539 */
+static bool
+fn_previously_found (tree decl, tree olddecl)
+{
+  int types_match;
+
+  if (olddecl == 0)
+    return false;
+
+  if (TREE_CODE (olddecl) == OVERLOAD)
+    {
+      if (OVL_CHAIN (olddecl) == NULL_TREE)
+	olddecl = OVL_CURRENT (olddecl);
+      else
+	{
+	  tree match;
+	  for (match = olddecl; match; match = OVL_NEXT (match))
+	    {
+	      if (fn_previously_found (decl, OVL_CURRENT (match)))
+		return true;
+	    }
+	  return false;
+	}
+    }	  
+
+  /* Don't warn about previously erroneous things that have the same
+     name.  */
+  if (TREE_TYPE (olddecl) == error_mark_node)
+    return true;
+
+  /* Internally defined things still need a prototype to escape the
+     warning.  */
+  if (DECL_ARTIFICIAL (olddecl))
+    return false;
+
+  if (TREE_CODE (olddecl) != FUNCTION_DECL)
+    return false;
+
+  /* These will match or error, don't also spew prototype warnings.  */
+  if (DECL_EXTERN_C_P (olddecl)
+      && DECL_EXTERN_C_P (decl))
+    return true;
+
+  /* These will match or error, don't also spew prototype warnings.  */
+  if (compparms (TYPE_ARG_TYPES (TREE_TYPE (decl)),
+		 TYPE_ARG_TYPES (TREE_TYPE (olddecl))))
+    return true;
+
+  types_match = decls_match (decl, olddecl);
+    
+  if (types_match)
+    return true;
+
+  return false;
+}
+
+inline static void
+check_missing_prototype (tree decl)
+{
+  if (warn_missing_prototypes
+      && namespace_bindings_p ()
+      && TREE_PUBLIC (decl)
+      && !DECL_MAIN_P (decl)
+      && DECL_NON_THUNK_FUNCTION_P (decl)
+      && ! DECL_FUNCTION_MEMBER_P (decl)
+      && DECL_NAMESPACE_SCOPE_P (decl)
+      && ! decl_anon_ns_mem_p (decl)
+      && ! DECL_DECLARED_INLINE_P (decl))
+    {
+      tree olddecl = namespace_binding (DECL_NAME (decl),  DECL_CONTEXT (decl));
+      if (!fn_previously_found (decl, olddecl))
+	warning (OPT_Wmissing_prototypes, "no previous prototype for %q+D", decl);
+    }
+}
+/* APPLE LOCAL end warn missing prototype 6261539 */
+
 /* Like start_preparsed_function, except that instead of a
    FUNCTION_DECL, this function takes DECLSPECS and DECLARATOR.
 
@@ -11253,6 +11798,8 @@ finish_function (int flags)
   tree fndecl = current_function_decl;
   tree fntype, ctype = NULL_TREE;
   int inclass_inline = (flags & 2) != 0;
+  /* APPLE LOCAL radar 6169580 */
+  int in_blocks_helper_function = (flags & 4) != 0;
   int nested;
 
   /* When we get some parse errors, we can end up without a
@@ -11446,7 +11993,8 @@ finish_function (int flags)
     maybe_end_member_template_processing ();
 
   /* Leave the scope of the class.  */
-  if (ctype)
+  /* APPLE LOCAL radar 6169580 */
+  if (ctype && !in_blocks_helper_function)
     pop_nested_class ();
 
   --function_depth;
@@ -11672,13 +12220,32 @@ cxx_maybe_build_cleanup (tree decl)
 {
   tree type = TREE_TYPE (decl);
 
-  if (type != error_mark_node && TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
+  /* APPLE LOCAL begin omit calls to empty destructors 5559195 */
+  tree dtor = NULL_TREE;
+  bool build_cleanup = false;
+
+  if (TREE_CODE (type) == RECORD_TYPE)
+    dtor = CLASSTYPE_DESTRUCTORS (type);
+
+  if (type != error_mark_node)
     {
+      if (TREE_CODE (type) == RECORD_TYPE)
+	/* For RECORD_TYPEs, we can refer to more precise flags than
+	   TYPE_HAS_NONTRIVIAL_DESTRUCTOR. */
+	build_cleanup = (dtor && TREE_PRIVATE (dtor))
+	  || CLASSTYPE_HAS_NONTRIVIAL_DESTRUCTOR_BODY (type)
+	  || CLASSTYPE_DESTRUCTOR_NONTRIVIAL_BECAUSE_OF_BASE (type);
+      else
+	build_cleanup = TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type);
+    }
+
+  if (build_cleanup)
+    {
+  /* APPLE LOCAL end omit calls to empty destructors 5559195 */
       int flags = LOOKUP_NORMAL|LOOKUP_DESTRUCTOR;
       tree rval;
       bool has_vbases = (TREE_CODE (type) == RECORD_TYPE
 			 && CLASSTYPE_VBASECLASSES (type));
-
       if (TREE_CODE (type) == ARRAY_TYPE)
 	rval = decl;
       else