Issue yuin#225: wrong compile time constant folding

yuin · yuin · commit c65cf424f6d8 · 2019-02-06T13:10:37.000+09:00
diff --git a/compile.go b/compile.go
@@ -1107,10 +1107,7 @@ func constFold(exp ast.Expr) ast.Expr { // {{{
 				panic(fmt.Sprintf("unknown binop: %v", expr.Operator))
 			}
 		} else {
-			retexpr := *expr
-			retexpr.Lhs = constFold(expr.Lhs)
-			retexpr.Rhs = constFold(expr.Rhs)
-			return &retexpr
+			return expr
 		}
 	case *ast.UnaryMinusOpExpr:
 		expr.Expr = constFold(expr.Expr)
diff --git a/go.mod b/go.mod
@@ -1,3 +1,8 @@
 module github.com/yuin/gopher-lua
 
-require github.com/chzyer/readline v0.0.0-20180603132655-2972be24d48e // indirect
+require (
+	github.com/chzyer/logex v1.1.10 // indirect
+	github.com/chzyer/readline v0.0.0-20180603132655-2972be24d48e
+	github.com/chzyer/test v0.0.0-20180213035817-a1ea475d72b1 // indirect
+	golang.org/x/sys v0.0.0-20190204203706-41f3e6584952 // indirect
+)
diff --git a/go.sum b/go.sum
@@ -1,2 +1,8 @@
+github.com/chzyer/logex v1.1.10 h1:Swpa1K6QvQznwJRcfTfQJmTE72DqScAa40E+fbHEXEE=
+github.com/chzyer/logex v1.1.10/go.mod h1:+Ywpsq7O8HXn0nuIou7OrIPyXbp3wmkHB+jjWRnGsAI=
 github.com/chzyer/readline v0.0.0-20180603132655-2972be24d48e h1:fY5BOSpyZCqRo5OhCuC+XN+r/bBCmeuuJtjz+bCNIf8=
 github.com/chzyer/readline v0.0.0-20180603132655-2972be24d48e/go.mod h1:nSuG5e5PlCu98SY8svDHJxuZscDgtXS6KTTbou5AhLI=
+github.com/chzyer/test v0.0.0-20180213035817-a1ea475d72b1 h1:q763qf9huN11kDQavWsoZXJNW3xEE4JJyHa5Q25/sd8=
+github.com/chzyer/test v0.0.0-20180213035817-a1ea475d72b1/go.mod h1:Q3SI9o4m/ZMnBNeIyt5eFwwo7qiLfzFZmjNmxjkiQlU=
+golang.org/x/sys v0.0.0-20190204203706-41f3e6584952 h1:FDfvYgoVsA7TTZSbgiqjAbfPbK47CNHdWl3h/PJtii0=
+golang.org/x/sys v0.0.0-20190204203706-41f3e6584952/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=

Original file line number	Diff line number	Diff line change
`@@ -1107,10 +1107,7 @@ func constFold(exp ast.Expr) ast.Expr { // {{{`
`1107`	`1107`	`panic(fmt.Sprintf("unknown binop: %v", expr.Operator))`
`1108`	`1108`	`}`
`1109`	`1109`	`} else {`
`1110`		`- retexpr := *expr`
`1111`		`- retexpr.Lhs = constFold(expr.Lhs)`
`1112`		`- retexpr.Rhs = constFold(expr.Rhs)`
`1113`		`- return &retexpr`
	`1110`	`+ return expr`
`1114`	`1111`	`}`
`1115`	`1112`	`case *ast.UnaryMinusOpExpr:`
`1116`	`1113`	`expr.Expr = constFold(expr.Expr)`