Revert "cmd/internal/gc: ignore declarations of types for goto validation"

This reverts commit 5726af54.

It broke all the builds.

Change-Id: I4b1dde86f9433717d303c1dabd6aa1a2bf97fab2
Reviewed-on: https://go-review.googlesource.com/10143Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

src/cmd/internal/gc/dcl.go

@@ -65,9 +65,6 @@ func popdcl() {
 		}
 		s = Pkglookup(d.Name, d.Pkg)
 		lno = int(s.Lastlineno)
-		if s.Def != nil {
-			d.whyPushed = s.Def.Op
-		}
 		dcopy(s, d)
 		d.Lastlineno = int32(lno)
 		if dflag() {

src/cmd/internal/gc/gen.go

@@ -159,21 +159,6 @@ func checkgoto(from *Node, to *Node) {
 		fs = fs.Link
 	}
 	if fs != to.Sym {
-		// more declarations at label than at goto.
-		// figure out if they are all types.
-		ts := to.Sym
-		ntt := nt
-		for ; ntt > nf; ntt-- {
-			if ts.whyPushed != OTYPE {
-				break
-			}
-			ts = ts.Link
-		}
-		// all types, nothing to see here.
-		if ntt == nf {
-			return
-		}
-
 		lno := int(lineno)
 		setlineno(from)
 
@@ -183,11 +168,11 @@ func checkgoto(from *Node, to *Node) {
 		var block *Sym
 
 		var dcl *Sym
-		ts = to.Sym
+		ts := to.Sym
 		for ; nt > nf; nt-- {
 			if ts.Pkg == nil {
 				block = ts
-			} else if ts.whyPushed != OTYPE {
+			} else {
 				dcl = ts
 			}
 			ts = ts.Link
@@ -196,7 +181,7 @@ func checkgoto(from *Node, to *Node) {
 		for ts != fs {
 			if ts.Pkg == nil {
 				block = ts
-			} else if ts.whyPushed != OTYPE {
+			} else {
 				dcl = ts
 			}
 			ts = ts.Link

src/cmd/internal/gc/go.go

@@ -111,7 +111,6 @@ type Sym struct {
 	Uniqgen   uint32
 	Importdef *Pkg   // where imported definition was found
 	Linkname  string // link name
-	whyPushed uint8  // why this symbol pushed onto dclstack. Same as Node.Op. Used by goto validation
 
 	// saved and restored by dcopy
 	Pkg        *Pkg

test/goto.go

@@ -536,19 +536,3 @@ func _() {
 		goto L // ERROR "goto L jumps into block starting at LINE-4|goto jumps into block"
 	}
 }
-
-// issue 8042
-func _() {
-	goto L
-	type a int
-	L:
-}
-
-// make sure we only complain about variable declarations.
-func _() {
-	goto L // ERROR "goto L jumps over declaration of x at LINE+2|goto jumps over declaration"
-	type a int
-	x := 1	// GCCGO_ERROR "defined here"
-	_ = x
-L:
-}