From: Robert Griesemer <gri@golang.org>
Date: Wed, 22 Mar 2023 21:04:43 +0000 (-0700)
Subject: go/types, types2: remove unnecessary tests for x.typ == Typ[Invalid]
X-Git-Tag: go1.21rc1~1134
X-Git-Url: http://www.git.cypherpunks.su/?a=commitdiff_plain;h=4c49d52439805c248f4a01d529b90b22e821b7d6;p=gostls13.git

go/types, types2: remove unnecessary tests for x.typ == Typ[Invalid]

In the worst case (x.mode != invalid but x.typ == Typ[Invalid]) we
may get unexpected additional errors; but we don't seem to have
any such situations, at least in the existing tests.

Change-Id: I86ae607b4ac9b926264bb6a967627c40e5a86ade
Reviewed-on: https://go-review.googlesource.com/c/go/+/478715
Reviewed-by: Robert Findley <rfindley@google.com>
Reviewed-by: Robert Griesemer <gri@google.com>
Auto-Submit: Robert Griesemer <gri@google.com>
Run-TryBot: Robert Griesemer <gri@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
---

diff --git a/src/cmd/compile/internal/types2/assignments.go b/src/cmd/compile/internal/types2/assignments.go
index afbb1186b5..9b130b48e1 100644
--- a/src/cmd/compile/internal/types2/assignments.go
+++ b/src/cmd/compile/internal/types2/assignments.go
@@ -99,7 +99,7 @@ func (check *Checker) assignment(x *operand, T Type, context string) {
 }
 
 func (check *Checker) initConst(lhs *Const, x *operand) {
-	if x.mode == invalid || x.typ == Typ[Invalid] || lhs.typ == Typ[Invalid] {
+	if x.mode == invalid || lhs.typ == Typ[Invalid] {
 		if lhs.typ == nil {
 			lhs.typ = Typ[Invalid]
 		}
@@ -130,7 +130,7 @@ func (check *Checker) initConst(lhs *Const, x *operand) {
 }
 
 func (check *Checker) initVar(lhs *Var, x *operand, context string) Type {
-	if x.mode == invalid || x.typ == Typ[Invalid] || lhs.typ == Typ[Invalid] {
+	if x.mode == invalid || lhs.typ == Typ[Invalid] {
 		if lhs.typ == nil {
 			lhs.typ = Typ[Invalid]
 		}
@@ -198,10 +198,6 @@ func (check *Checker) lhsVar(lhs syntax.Expr) Type {
 		v.used = v_used // restore v.used
 	}
 
-	if x.mode == invalid || x.typ == Typ[Invalid] {
-		return Typ[Invalid]
-	}
-
 	// spec: "Each left-hand side operand must be addressable, a map index
 	// expression, or the blank identifier. Operands may be parenthesized."
 	switch x.mode {
@@ -228,7 +224,7 @@ func (check *Checker) lhsVar(lhs syntax.Expr) Type {
 // assignVar checks the assignment lhs = x and returns the type of x.
 // If the assignment is invalid, the result is nil.
 func (check *Checker) assignVar(lhs syntax.Expr, x *operand) Type {
-	if x.mode == invalid || x.typ == Typ[Invalid] {
+	if x.mode == invalid {
 		check.useLHS(lhs)
 		return nil
 	}
diff --git a/src/go/types/assignments.go b/src/go/types/assignments.go
index e1b22d16ad..9d6a1ef4ed 100644
--- a/src/go/types/assignments.go
+++ b/src/go/types/assignments.go
@@ -97,7 +97,7 @@ func (check *Checker) assignment(x *operand, T Type, context string) {
 }
 
 func (check *Checker) initConst(lhs *Const, x *operand) {
-	if x.mode == invalid || x.typ == Typ[Invalid] || lhs.typ == Typ[Invalid] {
+	if x.mode == invalid || lhs.typ == Typ[Invalid] {
 		if lhs.typ == nil {
 			lhs.typ = Typ[Invalid]
 		}
@@ -128,7 +128,7 @@ func (check *Checker) initConst(lhs *Const, x *operand) {
 }
 
 func (check *Checker) initVar(lhs *Var, x *operand, context string) Type {
-	if x.mode == invalid || x.typ == Typ[Invalid] || lhs.typ == Typ[Invalid] {
+	if x.mode == invalid || lhs.typ == Typ[Invalid] {
 		if lhs.typ == nil {
 			lhs.typ = Typ[Invalid]
 		}
@@ -196,10 +196,6 @@ func (check *Checker) lhsVar(lhs ast.Expr) Type {
 		v.used = v_used // restore v.used
 	}
 
-	if x.mode == invalid || x.typ == Typ[Invalid] {
-		return Typ[Invalid]
-	}
-
 	// spec: "Each left-hand side operand must be addressable, a map index
 	// expression, or the blank identifier. Operands may be parenthesized."
 	switch x.mode {
@@ -226,7 +222,7 @@ func (check *Checker) lhsVar(lhs ast.Expr) Type {
 // assignVar checks the assignment lhs = x and returns the type of x.
 // If the assignment is invalid, the result is nil.
 func (check *Checker) assignVar(lhs ast.Expr, x *operand) Type {
-	if x.mode == invalid || x.typ == Typ[Invalid] {
+	if x.mode == invalid {
 		check.useLHS(lhs)
 		return nil
 	}