diff --git a/src/cmd/compile/internal/types2/issues_test.go b/src/cmd/compile/internal/types2/issues_test.go
index a856fcc..aea1cbb 100644
--- a/src/cmd/compile/internal/types2/issues_test.go
+++ b/src/cmd/compile/internal/types2/issues_test.go
@@ -852,7 +852,7 @@
 
 type Layout = C.struct_layout
 
-func (l /* ERROR "cannot define new methods on non-local type Layout" */ *Layout) Binding() {}
+func (l *Layout /* ERROR "cannot define new methods on non-local type Layout" */ ) Binding() {}
 
 func _() {
 	_ = (*Layout).Binding
diff --git a/src/cmd/compile/internal/types2/signature.go b/src/cmd/compile/internal/types2/signature.go
index 7199e9c..d316963 100644
--- a/src/cmd/compile/internal/types2/signature.go
+++ b/src/cmd/compile/internal/types2/signature.go
@@ -177,10 +177,7 @@
 		// parameters (wich may have the same name, see below).
 		var baseType *Named // nil if not valid
 		var cause string
-		if t := check.genericType(rbase, &cause); cause != "" {
-			check.errorf(rbase, InvalidRecv, "%s", cause)
-			// ok to continue
-		} else {
+		if t := check.genericType(rbase, &cause); isValid(t) {
 			switch t := t.(type) {
 			case *Named:
 				baseType = t
@@ -195,6 +192,11 @@
 			default:
 				panic("unreachable")
 			}
+		} else {
+			if cause != "" {
+				check.errorf(rbase, InvalidRecv, "%s", cause)
+			}
+			// Ok to continue but do not set baseType (see comment above).
 		}
 
 		// Collect the type parameters declared by the receiver (see also
@@ -269,7 +271,7 @@
 	// Delay validation of receiver type as it may cause premature expansion of types
 	// the receiver type is dependent on (see go.dev/issue/51232, go.dev/issue/51233).
 	check.later(func() {
-		check.validRecv(recv)
+		check.validRecv(rbase, recv)
 	}).describef(recv, "validRecv(%s)", recv)
 
 	return recv, recvTParamsList
@@ -400,7 +402,7 @@
 
 // validRecv verifies that the receiver satisfies its respective spec requirements
 // and reports an error otherwise.
-func (check *Checker) validRecv(recv *Var) {
+func (check *Checker) validRecv(pos poser, recv *Var) {
 	// spec: "The receiver type must be of the form T or *T where T is a type name."
 	rtyp, _ := deref(recv.typ)
 	atyp := Unalias(rtyp)
@@ -413,7 +415,7 @@
 	switch T := atyp.(type) {
 	case *Named:
 		if T.obj.pkg != check.pkg || isCGoTypeObj(T.obj) {
-			check.errorf(recv, InvalidRecv, "cannot define new methods on non-local type %s", rtyp)
+			check.errorf(pos, InvalidRecv, "cannot define new methods on non-local type %s", rtyp)
 			break
 		}
 		var cause string
@@ -431,12 +433,12 @@
 			panic("unreachable")
 		}
 		if cause != "" {
-			check.errorf(recv, InvalidRecv, "invalid receiver type %s (%s)", rtyp, cause)
+			check.errorf(pos, InvalidRecv, "invalid receiver type %s (%s)", rtyp, cause)
 		}
 	case *Basic:
-		check.errorf(recv, InvalidRecv, "cannot define new methods on non-local type %s", rtyp)
+		check.errorf(pos, InvalidRecv, "cannot define new methods on non-local type %s", rtyp)
 	default:
-		check.errorf(recv, InvalidRecv, "invalid receiver type %s", recv.typ)
+		check.errorf(pos, InvalidRecv, "invalid receiver type %s", recv.typ)
 	}
 }
 
diff --git a/src/cmd/compile/internal/types2/typexpr.go b/src/cmd/compile/internal/types2/typexpr.go
index 10af5e7..d955654 100644
--- a/src/cmd/compile/internal/types2/typexpr.go
+++ b/src/cmd/compile/internal/types2/typexpr.go
@@ -205,6 +205,10 @@
 // genericType is like typ but the type must be an (uninstantiated) generic
 // type. If cause is non-nil and the type expression was a valid type but not
 // generic, cause will be populated with a message describing the error.
+//
+// Note: If the type expression was invalid and an error was reported before,
+// cause will not be populated; thus cause alone cannot be used to determine
+// if an error occurred.
 func (check *Checker) genericType(e syntax.Expr, cause *string) Type {
 	typ := check.typInternal(e, nil)
 	assert(isTyped(typ))
diff --git a/src/go/types/issues_test.go b/src/go/types/issues_test.go
index 925ca0e..1c4c450 100644
--- a/src/go/types/issues_test.go
+++ b/src/go/types/issues_test.go
@@ -861,7 +861,7 @@
 
 type Layout = C.struct_layout
 
-func (l /* ERROR "cannot define new methods on non-local type Layout" */ *Layout) Binding() {}
+func (l *Layout /* ERROR "cannot define new methods on non-local type Layout" */ ) Binding() {}
 
 func _() {
 	_ = (*Layout).Binding
diff --git a/src/go/types/signature.go b/src/go/types/signature.go
index c0f2e61..681eb85 100644
--- a/src/go/types/signature.go
+++ b/src/go/types/signature.go
@@ -198,10 +198,7 @@
 		// parameters (wich may have the same name, see below).
 		var baseType *Named // nil if not valid
 		var cause string
-		if t := check.genericType(rbase, &cause); cause != "" {
-			check.errorf(rbase, InvalidRecv, "%s", cause)
-			// ok to continue
-		} else {
+		if t := check.genericType(rbase, &cause); isValid(t) {
 			switch t := t.(type) {
 			case *Named:
 				baseType = t
@@ -216,6 +213,11 @@
 			default:
 				panic("unreachable")
 			}
+		} else {
+			if cause != "" {
+				check.errorf(rbase, InvalidRecv, "%s", cause)
+			}
+			// Ok to continue but do not set baseType (see comment above).
 		}
 
 		// Collect the type parameters declared by the receiver (see also
@@ -299,7 +301,7 @@
 	// Delay validation of receiver type as it may cause premature expansion of types
 	// the receiver type is dependent on (see go.dev/issue/51232, go.dev/issue/51233).
 	check.later(func() {
-		check.validRecv(recv)
+		check.validRecv(rbase, recv)
 	}).describef(recv, "validRecv(%s)", recv)
 
 	return recv, recvTParamsList
@@ -420,7 +422,7 @@
 
 // validRecv verifies that the receiver satisfies its respective spec requirements
 // and reports an error otherwise.
-func (check *Checker) validRecv(recv *Var) {
+func (check *Checker) validRecv(pos positioner, recv *Var) {
 	// spec: "The receiver type must be of the form T or *T where T is a type name."
 	rtyp, _ := deref(recv.typ)
 	atyp := Unalias(rtyp)
@@ -433,7 +435,7 @@
 	switch T := atyp.(type) {
 	case *Named:
 		if T.obj.pkg != check.pkg || isCGoTypeObj(check.fset, T.obj) {
-			check.errorf(recv, InvalidRecv, "cannot define new methods on non-local type %s", rtyp)
+			check.errorf(pos, InvalidRecv, "cannot define new methods on non-local type %s", rtyp)
 			break
 		}
 		var cause string
@@ -451,12 +453,12 @@
 			panic("unreachable")
 		}
 		if cause != "" {
-			check.errorf(recv, InvalidRecv, "invalid receiver type %s (%s)", rtyp, cause)
+			check.errorf(pos, InvalidRecv, "invalid receiver type %s (%s)", rtyp, cause)
 		}
 	case *Basic:
-		check.errorf(recv, InvalidRecv, "cannot define new methods on non-local type %s", rtyp)
+		check.errorf(pos, InvalidRecv, "cannot define new methods on non-local type %s", rtyp)
 	default:
-		check.errorf(recv, InvalidRecv, "invalid receiver type %s", recv.typ)
+		check.errorf(pos, InvalidRecv, "invalid receiver type %s", recv.typ)
 	}
 }
 
diff --git a/src/go/types/typexpr.go b/src/go/types/typexpr.go
index 0b88f31..5bcbc2d 100644
--- a/src/go/types/typexpr.go
+++ b/src/go/types/typexpr.go
@@ -203,6 +203,10 @@
 // genericType is like typ but the type must be an (uninstantiated) generic
 // type. If cause is non-nil and the type expression was a valid type but not
 // generic, cause will be populated with a message describing the error.
+//
+// Note: If the type expression was invalid and an error was reported before,
+// cause will not be populated; thus cause alone cannot be used to determine
+// if an error occurred.
 func (check *Checker) genericType(e ast.Expr, cause *string) Type {
 	typ := check.typInternal(e, nil)
 	assert(isTyped(typ))
diff --git a/src/internal/types/testdata/check/decls2/decls2a.go b/src/internal/types/testdata/check/decls2/decls2a.go
index 2362bb9..58fdbfe 100644
--- a/src/internal/types/testdata/check/decls2/decls2a.go
+++ b/src/internal/types/testdata/check/decls2/decls2a.go
@@ -83,7 +83,7 @@
 // Methods associated with a named pointer type.
 type ptr *int
 func (ptr /* ERROR "invalid receiver" */ ) _() {}
-func (* /* ERROR "invalid receiver" */ ptr) _() {}
+func (*ptr /* ERROR "invalid receiver" */ ) _() {}
 
 // Methods with zero or multiple receivers.
 func ( /* ERROR "method has no receiver" */ ) _() {}
@@ -96,13 +96,13 @@
 func (int /* ERROR "cannot define new methods on non-local type int" */ ) m() {}
 func ([ /* ERROR "invalid receiver" */ ]int) m() {}
 func (time /* ERROR "cannot define new methods on non-local type time.Time" */ .Time) m() {}
-func (* /* ERROR "cannot define new methods on non-local type time.Time" */ time.Time) m() {}
-func (x /* ERROR "invalid receiver" */ interface{}) m() {}
+func (*time /* ERROR "cannot define new methods on non-local type time.Time" */ .Time) m() {}
+func (x any /* ERROR "invalid receiver" */ ) m() {}
 
 // Unsafe.Pointer is treated like a pointer when used as receiver type.
 type UP unsafe.Pointer
 func (UP /* ERROR "invalid" */ ) m1() {}
-func (* /* ERROR "invalid" */ UP) m2() {}
+func (*UP /* ERROR "invalid" */ ) m2() {}
 
 // Double declarations across package files
 const c_double = 0
diff --git a/src/internal/types/testdata/spec/receivers.go b/src/internal/types/testdata/spec/receivers.go
new file mode 100644
index 0000000..010c551
--- /dev/null
+++ b/src/internal/types/testdata/spec/receivers.go
@@ -0,0 +1,14 @@
+// -gotypesalias=1
+
+// Copyright 2024 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.
+
+package receivers
+
+// TODO(gri) add more tests checking the various restrictions on receivers
+
+type G[P any] struct{}
+type A[P any] = G[P]
+
+func (a A /* ERROR "cannot define new methods on generic alias type A[P any]" */ [P]) m() {}