only generate non-trivial signatures in the

file in which they occur.  avoids duplicate
trampoline generation across multiple files.

R=ken
OCL=20976
CL=20980

src/cmd/6g/obj.c

@@ -707,10 +707,12 @@ dumpsigt(Type *t0, Sym *s)
 
 	// set DUPOK to allow other .6s to contain
 	// the same signature.  only one will be chosen.
+	// should only happen for empty signatures
 	p = pc;
 	gins(AGLOBL, N, N);
 	p->from = at;
-	p->from.scale = DUPOK;
+	if(a == nil)
+		p->from.scale = DUPOK;
 	p->to = ac;
 	p->to.offset = ot;
 }
@@ -891,17 +893,20 @@ dumpsignatures(void)
 			continue;
 		s->siggen = 1;
 
-//print("dosig %T\n", t);
-		// don't emit signatures for *NamedStruct or interface if
-		// they were defined by other packages.
-		// (optimization)
+		// don't emit non-trivial signatures for types defined outside this file.
+		// non-trivial signatures might also drag in generated trampolines,
+		// and ar can't handle duplicates of the trampolines.
 		s1 = S;
-		if(isptr[et] && t->type != T)
+		if(isptr[et] && t->type != T) {
 			s1 = t->type->sym;
-		else if(et == TINTER)
+			if(s1 && !t->type->local)
+				continue;
+		}
+		else if(et == TINTER) {
 			s1 = t->sym;
-		if(s1 != S && strcmp(s1->opackage, package) != 0)
-			continue;
+			if(s1 && !t->local)
+				continue;
+		}
 
 		if(et == TINTER)
 			dumpsigi(t, s);

src/cmd/gc/dcl.c

@@ -78,7 +78,7 @@ dodcltype(Type *n)
 	addtyp(n, dclcontext);
 
 found:
-	n->sym->local = 1;
+	n->local = 1;
 	if(dcladj)
 		dcladj(n->sym);
 	return n;
@@ -118,6 +118,8 @@ updatetype(Type *n, Type *t)
 		fatal("updatetype %T / %T", n, t);
 	}
 
+	if(n->local)
+		t->local = 1;
 	*n = *t;
 	n->sym = s;
 
@@ -274,8 +276,8 @@ addmethod(Node *n, Type *t, int local)
 	st = pa->sym;
 	if(st == S)
 		goto bad;
-	if(local && !st->local) {
-		yyerror("method receiver type must be locally defined: %S", st);
+	if(local && !f->local) {
+		yyerror("method receiver type must be locally defined: %T", f);
 		return;
 	}
 
@@ -558,7 +560,6 @@ dcopy(Sym *a, Sym *b)
 	a->vargen = b->vargen;
 	a->block = b->block;
 	a->lastlineno = b->lastlineno;
-	a->local = b->local;
 	a->offset = b->offset;
 }
 
@@ -1233,7 +1234,7 @@ variter(Node *vv, Type *t, Node *ee)
 loop:
 	if(v == N && e == N)
 		return rev(r);
-	
+
 	if(v == N || e == N) {
 		yyerror("shape error in var dcl");
 		return rev(r);
@@ -1279,7 +1280,7 @@ loop:
 		iota += 1;
 		return;
 	}
-	
+
 	if(v == N || c == N) {
 		yyerror("shape error in var dcl");
 		iota += 1;

src/cmd/gc/export.c

@@ -203,7 +203,7 @@ dumptype(Type *t)
 		return;
 
 	// no need to dump type if it's not ours (was imported)
-	if(t->sym != S && t->sym->otype == t && !t->sym->local)
+	if(t->sym != S && t->sym->otype == t && !t->local)
 		return;
 
 	Bprint(bout, "type %#T %l#T\n",  t, t);

src/cmd/gc/go.h

@@ -157,6 +157,7 @@ struct	Type
 	uchar	siggen;
 	uchar	funarg;
 	uchar	copyany;
+	uchar	local;		// created in this file
 
 	// TFUNCT
 	uchar	thistuple;
@@ -238,7 +239,6 @@ struct	Sym
 	uchar	exported;	// exported
 	uchar	imported;	// imported
 	uchar	sym;		// huffman encoding in object file
-	uchar	local;		// created in this file
 	uchar	uniq;		// imbedded field name first found
 	uchar	siggen;		// signature generated
 

src/cmd/gc/walk.c

@@ -1465,7 +1465,7 @@ walkselect(Node *sel)
 				res = list(res, oc);
 				break;
 
-				
+
 			}
 			bod = N;
 			count++;
@@ -1699,6 +1699,7 @@ sigtype(Type *st)
 	t = newtype(s);
 	t = dodcltype(t);
 	updatetype(t, st);
+	t->local = 1;
 
 	// record internal type for signature generation
 	x = mal(sizeof(*x));