cmd/gc: fix incomplete export data when inlining with local variables.

When local declarations needed unexported types, these could
be missing in the export data.

Fixes build with -gcflags -lll, except for exp/gotype.

R=golang-dev, rsc, lvd
CC=golang-dev
https://golang.org/cl/6813067

src/cmd/gc/export.c

@@ -119,6 +119,17 @@ reexportdep(Node *n)
 		}
 		break;
 
+	case ODCL:
+		// Local variables in the bodies need their type.
+		t = n->left->type;
+		if(t != types[t->etype] && t != idealbool && t != idealstring) {
+			if(isptr[t->etype])
+				t = t->type;
+			if (t && t->sym && t->sym->def && t->sym->pkg != localpkg  && t->sym->pkg != builtinpkg) {
+				exportlist = list(exportlist, t->sym->def);
+			}
+		}
+		break;
 
 	case OLITERAL:
 		t = n->type;

test/fixedbugs/bug467.dir/p1.go

+package p1
+
+type SockaddrUnix int
+
+func (s SockaddrUnix) Error() string { return "blah" }

test/fixedbugs/bug467.dir/p2.go

+package p2
+
+import "./p1"
+
+func SockUnix() error { var s *p1.SockaddrUnix; return s }

test/fixedbugs/bug467.dir/p3.go

+package main
+
+import "./p2"
+
+func main() {
+	_ = p2.SockUnix()
+}

test/fixedbugs/bug467.go

+// compiledir
+
+// Copyright 2012 The Go Authors.  All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Exported data for inlining could forget types of
+// local variables declared in inlinable bodies.
+
+package ignored