diff --git a/compiler/analysis/info.go b/compiler/analysis/info.go
index c984b726f..304c8808a 100644
--- a/compiler/analysis/info.go
+++ b/compiler/analysis/info.go
@@ -93,7 +93,10 @@ func (info *Info) newFuncInfo(n ast.Node) *FuncInfo {
 }
 
 func (info *Info) IsBlocking(fun *types.Func) bool {
-	return len(info.FuncDeclInfos[fun].Blocking) > 0
+	if funInfo := info.FuncDeclInfos[fun]; funInfo != nil {
+		return len(funInfo.Blocking) > 0
+	}
+	panic(fmt.Errorf(`info did not have function declaration for %s`, fun.FullName()))
 }
 
 func AnalyzePkg(files []*ast.File, fileSet *token.FileSet, typesInfo *types.Info, typesPkg *types.Package, isBlocking func(*types.Func) bool) *Info {
diff --git a/compiler/expressions.go b/compiler/expressions.go
index db08cc31f..21971ab5f 100644
--- a/compiler/expressions.go
+++ b/compiler/expressions.go
@@ -267,7 +267,7 @@ func (fc *funcContext) translateExpr(expr ast.Expr) *expression {
 
 		case token.ARROW:
 			call := &ast.CallExpr{
-				Fun:  fc.newIdent("$recv", types.NewSignature(nil, types.NewTuple(types.NewVar(0, nil, "", t)), types.NewTuple(types.NewVar(0, nil, "", exprType), types.NewVar(0, nil, "", types.Typ[types.Bool])), false)),
+				Fun:  fc.newIdent("$recv", types.NewSignatureType(nil, nil, nil, types.NewTuple(types.NewVar(0, nil, "", t)), types.NewTuple(types.NewVar(0, nil, "", exprType), types.NewVar(0, nil, "", types.Typ[types.Bool])), false)),
 				Args: []ast.Expr{e.X},
 			}
 			fc.Blocking[call] = true
@@ -520,8 +520,11 @@ func (fc *funcContext) translateExpr(expr ast.Expr) *expression {
 			)
 		case *types.Basic:
 			return fc.formatExpr("%e.charCodeAt(%f)", e.X, e.Index)
+		case *types.Signature:
+			err := bailout(fmt.Errorf(`unsupported type parameters used at %s`, fc.pkgCtx.fileSet.Position(e.Pos())))
+			panic(err)
 		default:
-			panic(fmt.Sprintf("Unhandled IndexExpr: %T\n", t))
+			panic(fmt.Errorf(`unhandled IndexExpr: %T`, t))
 		}
 
 	case *ast.SliceExpr:
@@ -703,7 +706,7 @@ func (fc *funcContext) translateExpr(expr ast.Expr) *expression {
 					case "Float":
 						return fc.internalize(recv, types.Typ[types.Float64])
 					case "Interface":
-						return fc.internalize(recv, types.NewInterface(nil, nil))
+						return fc.internalize(recv, types.NewInterfaceType(nil, nil))
 					case "Unsafe":
 						return recv
 					default:
@@ -998,7 +1001,7 @@ func (fc *funcContext) translateBuiltin(name string, sig *types.Signature, args
 			panic(fmt.Sprintf("Unhandled cap type: %T\n", argType))
 		}
 	case "panic":
-		return fc.formatExpr("$panic(%s)", fc.translateImplicitConversion(args[0], types.NewInterface(nil, nil)))
+		return fc.formatExpr("$panic(%s)", fc.translateImplicitConversion(args[0], types.NewInterfaceType(nil, nil)))
 	case "append":
 		if ellipsis || len(args) == 1 {
 			argStr := fc.translateArgs(sig, args, ellipsis)
diff --git a/compiler/package.go b/compiler/package.go
index 93c22f1c5..ad918ba3e 100644
--- a/compiler/package.go
+++ b/compiler/package.go
@@ -131,6 +131,7 @@ func Compile(importPath string, files []*ast.File, fileSet *token.FileSet, impor
 		}
 		if fe, ok := bailingOut(e); ok {
 			// Orderly bailout, return whatever clues we already have.
+			fmt.Fprintf(fe, `building package %q`, importPath)
 			err = fe
 			return
 		}
@@ -269,7 +270,7 @@ func Compile(importPath string, files []*ast.File, fileSet *token.FileSet, impor
 	}
 	sort.Strings(importedPaths)
 	for _, impPath := range importedPaths {
-		id := funcCtx.newIdent(fmt.Sprintf(`%s.$init`, funcCtx.pkgCtx.pkgVars[impPath]), types.NewSignature(nil, nil, nil, false))
+		id := funcCtx.newIdent(fmt.Sprintf(`%s.$init`, funcCtx.pkgCtx.pkgVars[impPath]), types.NewSignatureType(nil, nil, nil, nil, nil, false))
 		call := &ast.CallExpr{Fun: id}
 		funcCtx.Blocking[call] = true
 		funcCtx.Flattened[call] = true
@@ -287,13 +288,6 @@ func Compile(importPath string, files []*ast.File, fileSet *token.FileSet, impor
 			switch d := decl.(type) {
 			case *ast.FuncDecl:
 				sig := funcCtx.pkgCtx.Defs[d.Name].(*types.Func).Type().(*types.Signature)
-				var recvType types.Type
-				if sig.Recv() != nil {
-					recvType = sig.Recv().Type()
-					if ptr, isPtr := recvType.(*types.Pointer); isPtr {
-						recvType = ptr.Elem()
-					}
-				}
 				if sig.Recv() == nil {
 					funcCtx.objectName(funcCtx.pkgCtx.Defs[d.Name].(*types.Func)) // register toplevel name
 				}
@@ -421,7 +415,7 @@ func Compile(importPath string, files []*ast.File, fileSet *token.FileSet, impor
 				d.DceObjectFilter = ""
 			case "init":
 				d.InitCode = funcCtx.CatchOutput(1, func() {
-					id := funcCtx.newIdent("", types.NewSignature(nil, nil, nil, false))
+					id := funcCtx.newIdent("", types.NewSignatureType(nil, nil, nil, nil, nil, false))
 					funcCtx.pkgCtx.Uses[id] = o
 					call := &ast.CallExpr{Fun: id}
 					if len(funcCtx.pkgCtx.FuncDeclInfos[o].Blocking) != 0 {
@@ -438,7 +432,14 @@ func Compile(importPath string, files []*ast.File, fileSet *token.FileSet, impor
 			if isPointer {
 				namedRecvType = ptr.Elem().(*types.Named)
 			}
-			d.NamedRecvType = funcCtx.objectName(namedRecvType.Obj())
+			if namedRecvType.TypeParams() != nil {
+				return nil, scanner.Error{
+					Pos: fileSet.Position(o.Pos()),
+					Msg: fmt.Sprintf("type %s: type parameters are not supported by GopherJS: https://github.com/gopherjs/gopherjs/issues/1013", o.FullName()),
+				}
+			}
+			name := funcCtx.objectName(namedRecvType.Obj())
+			d.NamedRecvType = name
 			d.DceObjectFilter = namedRecvType.Obj().Name()
 			if !fun.Name.IsExported() {
 				d.DceMethodFilter = o.Name() + "~"
@@ -454,7 +455,7 @@ func Compile(importPath string, files []*ast.File, fileSet *token.FileSet, impor
 		if mainFunc == nil {
 			return nil, fmt.Errorf("missing main function")
 		}
-		id := funcCtx.newIdent("", types.NewSignature(nil, nil, nil, false))
+		id := funcCtx.newIdent("", types.NewSignatureType(nil, nil, nil, nil, nil, false))
 		funcCtx.pkgCtx.Uses[id] = mainFunc
 		call := &ast.CallExpr{Fun: id}
 		ifStmt := &ast.IfStmt{
@@ -636,9 +637,9 @@ func (fc *funcContext) initArgs(ty types.Type) string {
 	case *types.Map:
 		return fmt.Sprintf("%s, %s", fc.typeName(t.Key()), fc.typeName(t.Elem()))
 	case *types.Pointer:
-		return fmt.Sprintf("%s", fc.typeName(t.Elem()))
+		return fc.typeName(t.Elem())
 	case *types.Slice:
-		return fmt.Sprintf("%s", fc.typeName(t.Elem()))
+		return fc.typeName(t.Elem())
 	case *types.Signature:
 		params := make([]string, t.Params().Len())
 		for i := range params {
@@ -660,6 +661,9 @@ func (fc *funcContext) initArgs(ty types.Type) string {
 			fields[i] = fmt.Sprintf(`{prop: "%s", name: %s, embedded: %t, exported: %t, typ: %s, tag: %s}`, fieldName(t, i), encodeString(field.Name()), field.Anonymous(), field.Exported(), fc.typeName(field.Type()), encodeString(t.Tag(i)))
 		}
 		return fmt.Sprintf(`"%s", [%s]`, pkgPath, strings.Join(fields, ", "))
+	case *types.TypeParam:
+		err := bailout(fmt.Errorf(`%v has unexpected generic type parameter %T`, ty, ty))
+		panic(err)
 	default:
 		err := bailout(fmt.Errorf("%v has unexpected type %T", ty, ty))
 		panic(err)
diff --git a/compiler/statements.go b/compiler/statements.go
index f8d791948..8518f9b71 100644
--- a/compiler/statements.go
+++ b/compiler/statements.go
@@ -32,7 +32,7 @@ func (fc *funcContext) translateStmt(stmt ast.Stmt, label *types.Label) {
 			panic(err) // Continue orderly bailout.
 		}
 
-		// Oh noes, we've tried to compile something so bad that compiler paniced
+		// Oh noes, we've tried to compile something so bad that compiler panicked
 		// and ran away. Let's gather some debugging clues.
 		bail := bailout(err)
 		pos := stmt.Pos()
@@ -471,7 +471,7 @@ func (fc *funcContext) translateStmt(stmt ast.Stmt, label *types.Label) {
 	case *ast.SendStmt:
 		chanType := fc.pkgCtx.TypeOf(s.Chan).Underlying().(*types.Chan)
 		call := &ast.CallExpr{
-			Fun:  fc.newIdent("$send", types.NewSignature(nil, types.NewTuple(types.NewVar(0, nil, "", chanType), types.NewVar(0, nil, "", chanType.Elem())), nil, false)),
+			Fun:  fc.newIdent("$send", types.NewSignatureType(nil, nil, nil, types.NewTuple(types.NewVar(0, nil, "", chanType), types.NewVar(0, nil, "", chanType.Elem())), nil, false)),
 			Args: []ast.Expr{s.Chan, fc.newIdent(fc.translateImplicitConversionWithCloning(s.Value, chanType.Elem()).String(), chanType.Elem())},
 		}
 		fc.Blocking[call] = true
@@ -522,8 +522,8 @@ func (fc *funcContext) translateStmt(stmt ast.Stmt, label *types.Label) {
 		}
 
 		selectCall := fc.setType(&ast.CallExpr{
-			Fun:  fc.newIdent("$select", types.NewSignature(nil, types.NewTuple(types.NewVar(0, nil, "", types.NewInterface(nil, nil))), types.NewTuple(types.NewVar(0, nil, "", types.Typ[types.Int])), false)),
-			Args: []ast.Expr{fc.newIdent(fmt.Sprintf("[%s]", strings.Join(channels, ", ")), types.NewInterface(nil, nil))},
+			Fun:  fc.newIdent("$select", types.NewSignatureType(nil, nil, nil, types.NewTuple(types.NewVar(0, nil, "", types.NewInterfaceType(nil, nil))), types.NewTuple(types.NewVar(0, nil, "", types.Typ[types.Int])), false)),
+			Args: []ast.Expr{fc.newIdent(fmt.Sprintf("[%s]", strings.Join(channels, ", ")), types.NewInterfaceType(nil, nil))},
 		}, types.Typ[types.Int])
 		if !hasDefault {
 			fc.Blocking[selectCall] = true
diff --git a/compiler/utils.go b/compiler/utils.go
index 8b18c29c1..058437f67 100644
--- a/compiler/utils.go
+++ b/compiler/utils.go
@@ -518,13 +518,13 @@ func isBlank(expr ast.Expr) bool {
 //
 // For example, consider a Go type:
 //
-//			 type SecretInt int
-//	    func (_ SecretInt) String() string { return "<secret>" }
+//	type SecretInt int
+//	func (_ SecretInt) String() string { return "<secret>" }
 //
-//	    func main() {
-//	      var i SecretInt = 1
-//	      println(i.String())
-//	    }
+//	func main() {
+//	  var i SecretInt = 1
+//	  println(i.String())
+//	}
 //
 // For this example the compiler will generate code similar to the snippet below:
 //
@@ -765,7 +765,7 @@ func (st signatureTypes) Param(i int, ellipsis bool) types.Type {
 	}
 	if !st.Sig.Variadic() {
 		// This should never happen if the code was type-checked successfully.
-		panic(fmt.Errorf("Tried to access parameter %d of a non-variadic signature %s", i, st.Sig))
+		panic(fmt.Errorf("tried to access parameter %d of a non-variadic signature %s", i, st.Sig))
 	}
 	if ellipsis {
 		return st.VariadicType()