cmd/compile: eliminate addmethod tpkg parameter

It's only needed for a check that can be pushed up into bimport.go,
where it makes more sense anyway.

Change-Id: I6ef381ff4f29627b0f390ce27fef08902932bea6
Reviewed-on: https://go-review.googlesource.com/28177
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

src/cmd/compile/internal/gc/bimport.go

@@ -467,6 +467,11 @@ func (p *importer) typ() *Type {
 			p.pos()
 			sym := p.fieldSym()
 
+			// during import unexported method names should be in the type's package
+			if !exportname(sym.Name) && sym.Pkg != tsym.Pkg {
+				Fatalf("imported method name %v in wrong package %s\n", sconv(sym, FmtSign), tsym.Pkg.Name)
+			}
+
 			recv := p.paramList() // TODO(gri) do we need a full param list for the receiver?
 			params := p.paramList()
 			result := p.paramList()
@@ -475,7 +480,7 @@ func (p *importer) typ() *Type {
 			n := methodname(newname(sym), recv[0].Right)
 			n.Type = functype(recv[0], params, result)
 			checkwidth(n.Type)
-			addmethod(sym, n.Type, tsym.Pkg, false, nointerface)
+			addmethod(sym, n.Type, false, nointerface)
 			p.funcList = append(p.funcList, n)
 			importlist = append(importlist, n)
 

src/cmd/compile/internal/gc/dcl.go

@@ -1153,8 +1153,7 @@ func methodname(n *Node, t *Node) *Node {
 // Add a method, declared as a function.
 // - msym is the method symbol
 // - t is function type (with receiver)
-// - tpkg is the package of the type declaring the method during import, or nil (ignored) --- for verification only
-func addmethod(msym *Sym, t *Type, tpkg *Pkg, local, nointerface bool) {
+func addmethod(msym *Sym, t *Type, local, nointerface bool) {
 	// get field sym
 	if msym == nil {
 		Fatalf("no method symbol")
@@ -1232,11 +1231,6 @@ func addmethod(msym *Sym, t *Type, tpkg *Pkg, local, nointerface bool) {
 	f := structfield(n)
 	f.Nointerface = nointerface
 
-	// during import unexported method names should be in the type's package
-	if tpkg != nil && f.Sym != nil && !exportname(f.Sym.Name) && f.Sym.Pkg != tpkg {
-		Fatalf("imported method name %v in wrong package %s\n", sconv(f.Sym, FmtSign), tpkg.Name)
-	}
-
 	mt.Methods().Append(f)
 }
 

src/cmd/compile/internal/gc/typecheck.go

@@ -3388,7 +3388,7 @@ func typecheckfunc(n *Node) {
 	t.SetNname(n.Func.Nname)
 	rcvr := t.Recv()
 	if rcvr != nil && n.Func.Shortname != nil {
-		addmethod(n.Func.Shortname.Sym, t, nil, true, n.Func.Pragma&Nointerface != 0)
+		addmethod(n.Func.Shortname.Sym, t, true, n.Func.Pragma&Nointerface != 0)
 	}
 
 	for _, ln := range n.Func.Dcl {