gc: pass FlagNoPointers to runtime.new

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/5151043

src/cmd/gc/builtin.c.boot

 char *runtimeimport =
 	"package runtime\n"
 	"import runtime \"runtime\"\n"
-	"func @\"\".new (? int32) *any\n"
+	"func @\"\".new (typ *uint8) *any\n"
 	"func @\"\".panicindex ()\n"
 	"func @\"\".panicslice ()\n"
 	"func @\"\".throwreturn ()\n"

src/cmd/gc/runtime.go

@@ -10,7 +10,7 @@ package PACKAGE
 
 // emitted by compiler, not referred to by go programs
 
-func new(int32) *any
+func new(typ *byte) *any
 func panicindex()
 func panicslice()
 func throwreturn()

src/cmd/gc/walk.c

@@ -1686,7 +1686,7 @@ callnew(Type *t)
 	dowidth(t);
 	fn = syslook("new", 1);
 	argtype(fn, t);
-	return mkcall1(fn, ptrto(t), nil, nodintconst(t->width));
+	return mkcall1(fn, ptrto(t), nil, typename(t));
 }
 
 static Node*

src/pkg/runtime/malloc.goc

@@ -393,8 +393,10 @@ runtime·mal(uintptr n)
 	return runtime·mallocgc(n, 0, 1, 1);
 }
 
-func new(n uint32) (ret *uint8) {
-	ret = runtime·mal(n);
+func new(typ *Type) (ret *uint8) {
+	uint32 flag = typ->kind&KindNoPointers ? FlagNoPointers : 0;
+	ret = runtime·mallocgc(typ->size, flag, 1, 1);
+	FLUSH(&ret);
 }
 
 void*