diff --git a/src/cmd/5g/cgen64.go b/src/cmd/5g/cgen64.go
index 05f2e1e..f7b52b6 100644
--- a/src/cmd/5g/cgen64.go
+++ b/src/cmd/5g/cgen64.go
@@ -24,7 +24,7 @@
 
 	l := n.Left
 	var t1 gc.Node
-	if l.Addable == 0 {
+	if !l.Addable {
 		gc.Tempname(&t1, l.Type)
 		gc.Cgen(l, &t1)
 		l = &t1
@@ -108,7 +108,7 @@
 	// setup for binary operators
 	r := n.Right
 
-	if r != nil && r.Addable == 0 {
+	if r != nil && !r.Addable {
 		var t2 gc.Node
 		gc.Tempname(&t2, r.Type)
 		gc.Cgen(r, &t2)
diff --git a/src/cmd/5g/gsubr.go b/src/cmd/5g/gsubr.go
index fe4ed8d..ed72a9a 100644
--- a/src/cmd/5g/gsubr.go
+++ b/src/cmd/5g/gsubr.go
@@ -1090,7 +1090,7 @@
 	var oary [10]int64
 	var nn *gc.Node
 	o := gc.Dotoffset(n, oary[:], &nn)
-	if nn != nil && nn.Addable != 0 && o == 1 && oary[0] >= 0 {
+	if nn != nil && nn.Addable && o == 1 && oary[0] >= 0 {
 		*n1 = *nn
 		n1.Type = n.Type
 		n1.Xoffset += oary[0]
@@ -1169,7 +1169,7 @@
 			return false
 		}
 
-		if nn.Addable != 0 && o == 1 && oary[0] >= 0 {
+		if nn.Addable && o == 1 && oary[0] >= 0 {
 			// directly addressable set of DOTs
 			n1 := *nn
 
diff --git a/src/cmd/6g/gsubr.go b/src/cmd/6g/gsubr.go
index 323ea69..e2fad6f 100644
--- a/src/cmd/6g/gsubr.go
+++ b/src/cmd/6g/gsubr.go
@@ -1247,7 +1247,7 @@
 			return false
 		}
 
-		if nn.Addable != 0 && o == 1 && oary[0] >= 0 {
+		if nn.Addable && o == 1 && oary[0] >= 0 {
 			// directly addressable set of DOTs
 			n1 := *nn
 
diff --git a/src/cmd/8g/cgen.go b/src/cmd/8g/cgen.go
index 5546aba3..0b93694 100644
--- a/src/cmd/8g/cgen.go
+++ b/src/cmd/8g/cgen.go
@@ -17,7 +17,7 @@
  */
 func igenindex(n *gc.Node, res *gc.Node, bounded bool) *obj.Prog {
 	if !gc.Is64(n.Type) {
-		if n.Addable != 0 {
+		if n.Addable {
 			// nothing to do.
 			*res = *n
 		} else {
@@ -58,13 +58,13 @@
 	gc.Tempname(&tsrc, gc.Types[gc.Tptr])
 	var tdst gc.Node
 	gc.Tempname(&tdst, gc.Types[gc.Tptr])
-	if n.Addable == 0 {
+	if !n.Addable {
 		gc.Agen(n, &tsrc)
 	}
-	if res.Addable == 0 {
+	if !res.Addable {
 		gc.Agen(res, &tdst)
 	}
-	if n.Addable != 0 {
+	if n.Addable {
 		gc.Agen(n, &src)
 	} else {
 		gmove(&tsrc, &src)
@@ -74,7 +74,7 @@
 		gc.Gvardef(res)
 	}
 
-	if res.Addable != 0 {
+	if res.Addable {
 		gc.Agen(res, &dst)
 	} else {
 		gmove(&tdst, &dst)
diff --git a/src/cmd/8g/cgen64.go b/src/cmd/8g/cgen64.go
index ee04bdb..7fb6549 100644
--- a/src/cmd/8g/cgen64.go
+++ b/src/cmd/8g/cgen64.go
@@ -63,14 +63,14 @@
 
 	l := n.Left
 	r := n.Right
-	if l.Addable == 0 {
+	if !l.Addable {
 		var t1 gc.Node
 		gc.Tempname(&t1, l.Type)
 		gc.Cgen(l, &t1)
 		l = &t1
 	}
 
-	if r != nil && r.Addable == 0 {
+	if r != nil && !r.Addable {
 		var t2 gc.Node
 		gc.Tempname(&t2, r.Type)
 		gc.Cgen(r, &t2)
diff --git a/src/cmd/8g/ggen.go b/src/cmd/8g/ggen.go
index a4a373c..115c962 100644
--- a/src/cmd/8g/ggen.go
+++ b/src/cmd/8g/ggen.go
@@ -637,7 +637,7 @@
 		// binary
 		if nl.Ullman >= nr.Ullman {
 			gc.Cgen(nl, &f0)
-			if nr.Addable != 0 {
+			if nr.Addable {
 				gins(foptoas(int(n.Op), n.Type, 0), nr, &f0)
 			} else {
 				gc.Cgen(nr, &f0)
@@ -645,7 +645,7 @@
 			}
 		} else {
 			gc.Cgen(nr, &f0)
-			if nl.Addable != 0 {
+			if nl.Addable {
 				gins(foptoas(int(n.Op), n.Type, Frev), nl, &f0)
 			} else {
 				gc.Cgen(nl, &f0)
@@ -762,14 +762,14 @@
 	var n2 gc.Node
 	var ax gc.Node
 	if !gc.Thearch.Use387 {
-		if nl.Addable == 0 {
+		if !nl.Addable {
 			var n1 gc.Node
 			gc.Tempname(&n1, nl.Type)
 			gc.Cgen(nl, &n1)
 			nl = &n1
 		}
 
-		if nr.Addable == 0 {
+		if !nr.Addable {
 			var tmp gc.Node
 			gc.Tempname(&tmp, nr.Type)
 			gc.Cgen(nr, &tmp)
diff --git a/src/cmd/8g/gsubr.go b/src/cmd/8g/gsubr.go
index 929cbae..76c67af 100644
--- a/src/cmd/8g/gsubr.go
+++ b/src/cmd/8g/gsubr.go
@@ -1732,7 +1732,7 @@
 	var oary [10]int64
 	var nn *gc.Node
 	o := gc.Dotoffset(n, oary[:], &nn)
-	if nn != nil && nn.Addable != 0 && o == 1 && oary[0] >= 0 {
+	if nn != nil && nn.Addable && o == 1 && oary[0] >= 0 {
 		*n1 = *nn
 		n1.Type = n.Type
 		n1.Xoffset += oary[0]
diff --git a/src/cmd/internal/gc/cgen.go b/src/cmd/internal/gc/cgen.go
index d3921f7..3b628ac 100644
--- a/src/cmd/internal/gc/cgen.go
+++ b/src/cmd/internal/gc/cgen.go
@@ -34,7 +34,7 @@
 
 	switch n.Op {
 	case OSLICE, OSLICEARR, OSLICESTR, OSLICE3, OSLICE3ARR:
-		if res.Op != ONAME || res.Addable == 0 {
+		if res.Op != ONAME || !res.Addable {
 			var n1 Node
 			Tempname(&n1, n.Type)
 			Cgen_slice(n, &n1)
@@ -45,7 +45,7 @@
 		return
 
 	case OEFACE:
-		if res.Op != ONAME || res.Addable == 0 {
+		if res.Op != ONAME || !res.Addable {
 			var n1 Node
 			Tempname(&n1, n.Type)
 			Cgen_eface(n, &n1)
@@ -81,7 +81,7 @@
 		return
 	}
 
-	if res.Addable == 0 {
+	if !res.Addable {
 		if n.Ullman > res.Ullman {
 			if Ctxt.Arch.Regsize == 4 && Is64(n.Type) {
 				var n1 Node
@@ -188,7 +188,7 @@
 
 	if Ctxt.Arch.Thechar == '5' { // TODO(rsc): Maybe more often?
 		// if both are addressable, move
-		if n.Addable != 0 && res.Addable != 0 {
+		if n.Addable && res.Addable {
 			if Is64(n.Type) || Is64(res.Type) || n.Op == OREGISTER || res.Op == OREGISTER || Iscomplex[n.Type.Etype] || Iscomplex[res.Type.Etype] {
 				Thearch.Gmove(n, res)
 			} else {
@@ -203,7 +203,7 @@
 		}
 
 		// if both are not addressable, use a temporary.
-		if n.Addable == 0 && res.Addable == 0 {
+		if !n.Addable && !res.Addable {
 			// could use regalloc here sometimes,
 			// but have to check for ullman >= UINF.
 			var n1 Node
@@ -215,7 +215,7 @@
 
 		// if result is not addressable directly but n is,
 		// compute its address and then store via the address.
-		if res.Addable == 0 {
+		if !res.Addable {
 			var n1 Node
 			Igen(res, &n1, nil)
 			Cgen(n, &n1)
@@ -229,14 +229,14 @@
 		return
 	}
 
-	if (Ctxt.Arch.Thechar == '6' || Ctxt.Arch.Thechar == '8') && n.Addable != 0 {
+	if (Ctxt.Arch.Thechar == '6' || Ctxt.Arch.Thechar == '8') && n.Addable {
 		Thearch.Gmove(n, res)
 		return
 	}
 
 	if Ctxt.Arch.Thechar == '7' || Ctxt.Arch.Thechar == '9' {
 		// if both are addressable, move
-		if n.Addable != 0 {
+		if n.Addable {
 			if n.Op == OREGISTER || res.Op == OREGISTER {
 				Thearch.Gmove(n, res)
 			} else {
@@ -458,7 +458,7 @@
 		var n1 Node
 		var n2 Node
 		if Ctxt.Arch.Thechar == '5' {
-			if nl.Addable != 0 && !Is64(nl.Type) {
+			if nl.Addable && !Is64(nl.Type) {
 				Regalloc(&n1, nl.Type, res)
 				Thearch.Gmove(nl, &n1)
 			} else {
@@ -795,7 +795,7 @@
 func Mgen(n *Node, n1 *Node, rg *Node) {
 	n1.Op = OEMPTY
 
-	if n.Addable != 0 {
+	if n.Addable {
 		*n1 = *n
 		if n1.Op == OREGISTER || n1.Op == OINDREG {
 			reg[n.Val.U.Reg-int16(Thearch.REGMIN)]++
@@ -832,7 +832,7 @@
 		Fatal("cgenr on fat node")
 	}
 
-	if n.Addable != 0 {
+	if n.Addable {
 		Regalloc(a, n.Type, res)
 		Thearch.Gmove(n, a)
 		return
@@ -891,7 +891,7 @@
 			bounded := Debug['B'] != 0 || n.Bounded
 			var n1 Node
 			var n3 Node
-			if nr.Addable != 0 {
+			if nr.Addable {
 				var tmp Node
 				if !Isconst(nr, CTINT) {
 					Tempname(&tmp, Types[TINT32])
@@ -904,7 +904,7 @@
 					Regalloc(&n1, tmp.Type, nil)
 					Thearch.Gmove(&tmp, &n1)
 				}
-			} else if nl.Addable != 0 {
+			} else if nl.Addable {
 				if !Isconst(nr, CTINT) {
 					var tmp Node
 					Tempname(&tmp, Types[TINT32])
@@ -1040,7 +1040,7 @@
 			var n3 Node
 			var tmp Node
 			var n1 Node
-			if nr.Addable != 0 {
+			if nr.Addable {
 				// Generate &nl first, and move nr into register.
 				if !Isconst(nl, CTSTR) {
 					Igen(nl, &n3, res)
@@ -1050,7 +1050,7 @@
 					Regalloc(&n1, tmp.Type, nil)
 					Thearch.Gmove(&tmp, &n1)
 				}
-			} else if nl.Addable != 0 {
+			} else if nl.Addable {
 				// Generate nr first, and move &nl into register.
 				if !Isconst(nr, CTINT) {
 					p2 = Thearch.Igenindex(nr, &tmp, bounded)
@@ -1201,10 +1201,10 @@
 		var nlen Node
 		var tmp Node
 		var n1 Node
-		if nr.Addable != 0 {
+		if nr.Addable {
 			goto irad
 		}
-		if nl.Addable != 0 {
+		if nl.Addable {
 			Cgenr(nr, &n1, nil)
 			if !Isconst(nl, CTSTR) {
 				if Isfixedarray(nl.Type) {
@@ -1233,7 +1233,7 @@
 			if Isfixedarray(nl.Type) {
 				Agenr(nl, &n3, res)
 			} else {
-				if nl.Addable == 0 {
+				if !nl.Addable {
 					if res != nil && res.Op == OREGISTER { // give up res, which we don't need yet.
 						Regfree(res)
 					}
@@ -1432,7 +1432,7 @@
 		return
 	}
 
-	if n.Addable != 0 {
+	if n.Addable {
 		if n.Op == OREGISTER {
 			Fatal("agen OREGISTER")
 		}
@@ -1592,7 +1592,7 @@
 		*a = Node{}
 		a.Op = OINDREG
 		a.Val.U.Reg = int16(Thearch.REGSP)
-		a.Addable = 1
+		a.Addable = true
 		a.Xoffset = fp.Width
 		if HasLinkRegister() {
 			a.Xoffset += int64(Ctxt.Arch.Ptrsize)
@@ -1692,7 +1692,7 @@
 		return
 
 	case ONAME:
-		if n.Addable == 0 || Ctxt.Arch.Thechar == '5' || Ctxt.Arch.Thechar == '7' || Ctxt.Arch.Thechar == '9' {
+		if !n.Addable || Ctxt.Arch.Thechar == '5' || Ctxt.Arch.Thechar == '7' || Ctxt.Arch.Thechar == '9' {
 			goto def
 		}
 		var n1 Node
@@ -1824,14 +1824,14 @@
 		}
 
 		if Ctxt.Arch.Regsize == 4 && Is64(nr.Type) {
-			if nl.Addable == 0 || Isconst(nl, CTINT) {
+			if !nl.Addable || Isconst(nl, CTINT) {
 				var n1 Node
 				Tempname(&n1, nl.Type)
 				Cgen(nl, &n1)
 				nl = &n1
 			}
 
-			if nr.Addable == 0 {
+			if !nr.Addable {
 				var n2 Node
 				Tempname(&n2, nr.Type)
 				Cgen(nr, &n2)
@@ -1862,7 +1862,7 @@
 			goto cmp
 		}
 
-		if nl.Addable == 0 && Ctxt.Arch.Thechar == '8' {
+		if !nl.Addable && Ctxt.Arch.Thechar == '8' {
 			Tempname(&n1, nl.Type)
 		} else {
 			Regalloc(&n1, nl.Type, nil)
@@ -1879,7 +1879,7 @@
 			break
 		}
 
-		if nr.Addable == 0 && Ctxt.Arch.Thechar == '8' {
+		if !nr.Addable && Ctxt.Arch.Thechar == '8' {
 			var tmp Node
 			Tempname(&tmp, nr.Type)
 			Cgen(nr, &tmp)
@@ -2199,7 +2199,7 @@
 
 	i = i.Left // interface
 
-	if i.Addable == 0 {
+	if !i.Addable {
 		var tmpi Node
 		Tempname(&tmpi, i.Type)
 		Cgen(i, &tmpi)
@@ -2304,7 +2304,7 @@
 	}
 
 	// call direct
-	n.Left.Method = 1
+	n.Left.Method = true
 
 	Ginscall(n.Left, proc)
 }
@@ -2334,7 +2334,7 @@
 	var nod Node
 	nod.Op = OINDREG
 	nod.Val.U.Reg = int16(Thearch.REGSP)
-	nod.Addable = 1
+	nod.Addable = true
 
 	nod.Xoffset = fp.Width
 	if HasLinkRegister() {
@@ -2364,7 +2364,7 @@
 	var nod1 Node
 	nod1.Op = OINDREG
 	nod1.Val.U.Reg = int16(Thearch.REGSP)
-	nod1.Addable = 1
+	nod1.Addable = true
 	nod1.Xoffset = fp.Width
 	if HasLinkRegister() {
 		nod1.Xoffset += int64(Ctxt.Arch.Ptrsize)
diff --git a/src/cmd/internal/gc/closure.go b/src/cmd/internal/gc/closure.go
index a5364fc..62e060e 100644
--- a/src/cmd/internal/gc/closure.go
+++ b/src/cmd/internal/gc/closure.go
@@ -599,7 +599,7 @@
 	ptr := Nod(ONAME, nil, nil)
 	ptr.Sym = Lookup("rcvr")
 	ptr.Class = PAUTO
-	ptr.Addable = 1
+	ptr.Addable = true
 	ptr.Ullman = 1
 	ptr.Used = true
 	ptr.Curfn = xfunc
diff --git a/src/cmd/internal/gc/cplx.go b/src/cmd/internal/gc/cplx.go
index fe4c38c..ec6984c 100644
--- a/src/cmd/internal/gc/cplx.go
+++ b/src/cmd/internal/gc/cplx.go
@@ -23,13 +23,13 @@
 
 	// make both sides addable in ullman order
 	if nr != nil {
-		if nl.Ullman > nr.Ullman && nl.Addable == 0 {
+		if nl.Ullman > nr.Ullman && !nl.Addable {
 			Tempname(&tnl, nl.Type)
 			Cgen(nl, &tnl)
 			nl = &tnl
 		}
 
-		if nr.Addable == 0 {
+		if !nr.Addable {
 			var tnr Node
 			Tempname(&tnr, nr.Type)
 			Cgen(nr, &tnr)
@@ -37,7 +37,7 @@
 		}
 	}
 
-	if nl.Addable == 0 {
+	if !nl.Addable {
 		Tempname(&tnl, nl.Type)
 		Cgen(nl, &tnl)
 		nl = &tnl
@@ -83,7 +83,7 @@
 
 // break addable nc-complex into nr-real and ni-imaginary
 func subnode(nr *Node, ni *Node, nc *Node) {
-	if nc.Addable == 0 {
+	if !nc.Addable {
 		Fatal("subnode not addable")
 	}
 
@@ -227,7 +227,7 @@
 func nodfconst(n *Node, t *Type, fval *Mpflt) {
 	*n = Node{}
 	n.Op = OLITERAL
-	n.Addable = 1
+	n.Addable = true
 	ullmancalc(n)
 	n.Val.U.Fval = fval
 	n.Val.Ctype = CTFLT
@@ -291,7 +291,7 @@
 		Dump("complexmove-t", t)
 	}
 
-	if t.Addable == 0 {
+	if !t.Addable {
 		Fatal("complexmove: to not addable")
 	}
 
@@ -308,7 +308,7 @@
 		TCOMPLEX64<<16 | TCOMPLEX128,
 		TCOMPLEX128<<16 | TCOMPLEX64,
 		TCOMPLEX128<<16 | TCOMPLEX128:
-		if f.Addable == 0 || overlap_cplx(f, t) {
+		if !f.Addable || overlap_cplx(f, t) {
 			var tmp Node
 			Tempname(&tmp, f.Type)
 			Complexmove(f, &tmp)
@@ -340,7 +340,7 @@
 	// pick off float/complex opcodes
 	switch n.Op {
 	case OCOMPLEX:
-		if res.Addable != 0 {
+		if res.Addable {
 			var n1 Node
 			var n2 Node
 			subnode(&n1, &n2, res)
@@ -354,7 +354,7 @@
 
 	case OREAL, OIMAG:
 		nl := n.Left
-		if nl.Addable == 0 {
+		if !nl.Addable {
 			var tmp Node
 			Tempname(&tmp, nl.Type)
 			Complexgen(nl, &tmp)
@@ -380,7 +380,7 @@
 	tr := Simsimtype(n.Type)
 	tr = cplxsubtype(tr)
 	if tl != tr {
-		if n.Addable == 0 {
+		if !n.Addable {
 			var n1 Node
 			Tempname(&n1, n.Type)
 			Complexmove(n, &n1)
@@ -391,7 +391,7 @@
 		return
 	}
 
-	if res.Addable == 0 {
+	if !res.Addable {
 		var n1 Node
 		Igen(res, &n1, nil)
 		Cgen(n, &n1)
@@ -399,7 +399,7 @@
 		return
 	}
 
-	if n.Addable != 0 {
+	if n.Addable {
 		Complexmove(n, res)
 		return
 	}
@@ -444,13 +444,13 @@
 	// make both sides addable in ullman order
 	var tnl Node
 	if nr != nil {
-		if nl.Ullman > nr.Ullman && nl.Addable == 0 {
+		if nl.Ullman > nr.Ullman && !nl.Addable {
 			Tempname(&tnl, nl.Type)
 			Cgen(nl, &tnl)
 			nl = &tnl
 		}
 
-		if nr.Addable == 0 {
+		if !nr.Addable {
 			var tnr Node
 			Tempname(&tnr, nr.Type)
 			Cgen(nr, &tnr)
@@ -458,7 +458,7 @@
 		}
 	}
 
-	if nl.Addable == 0 {
+	if !nl.Addable {
 		Tempname(&tnl, nl.Type)
 		Cgen(nl, &tnl)
 		nl = &tnl
diff --git a/src/cmd/internal/gc/dcl.go b/src/cmd/internal/gc/dcl.go
index c8375dd..786b7b2 100644
--- a/src/cmd/internal/gc/dcl.go
+++ b/src/cmd/internal/gc/dcl.go
@@ -367,7 +367,7 @@
 	n := Nod(ONAME, nil, nil)
 	n.Sym = s
 	n.Type = nil
-	n.Addable = 1
+	n.Addable = true
 	n.Ullman = 1
 	n.Xoffset = 0
 	return n
@@ -438,7 +438,7 @@
 			c.Class = PPARAMREF
 			c.Isddd = n.Isddd
 			c.Defn = n
-			c.Addable = 0
+			c.Addable = false
 			c.Ullman = 2
 			c.Funcdepth = Funcdepth
 			c.Outer = n.Closure
@@ -521,7 +521,7 @@
 	as := Nod(OAS2, nil, nil)
 	as.List = left
 	as.Rlist = right
-	as.Colas = 1
+	as.Colas = true
 	as.Lineno = lno
 	colasdefn(left, as)
 
diff --git a/src/cmd/internal/gc/fmt.go b/src/cmd/internal/gc/fmt.go
index e5b9e56..38e358a 100644
--- a/src/cmd/internal/gc/fmt.go
+++ b/src/cmd/internal/gc/fmt.go
@@ -201,7 +201,7 @@
 		fmt.Fprintf(&buf, " u(%d)", n.Ullman)
 	}
 
-	if c == 0 && n.Addable != 0 {
+	if c == 0 && n.Addable {
 		fmt.Fprintf(&buf, " a(%d)", n.Addable)
 	}
 
@@ -229,7 +229,7 @@
 		}
 	}
 
-	if n.Colas != 0 {
+	if n.Colas {
 		fmt.Fprintf(&buf, " colas(%d)", n.Colas)
 	}
 
@@ -822,7 +822,7 @@
 			break
 		}
 
-		if n.Colas != 0 && !complexinit {
+		if n.Colas && !complexinit {
 			f += fmt.Sprintf("%v := %v", Nconv(n.Left, 0), Nconv(n.Right, 0))
 		} else {
 			f += fmt.Sprintf("%v = %v", Nconv(n.Left, 0), Nconv(n.Right, 0))
@@ -841,7 +841,7 @@
 		f += fmt.Sprintf("%v %v= %v", Nconv(n.Left, 0), Oconv(int(n.Etype), obj.FmtSharp), Nconv(n.Right, 0))
 
 	case OAS2:
-		if n.Colas != 0 && !complexinit {
+		if n.Colas && !complexinit {
 			f += fmt.Sprintf("%v := %v", Hconv(n.List, obj.FmtComma), Hconv(n.Rlist, obj.FmtComma))
 			break
 		}
diff --git a/src/cmd/internal/gc/gen.go b/src/cmd/internal/gc/gen.go
index e0659fc..e52ff65 100644
--- a/src/cmd/internal/gc/gen.go
+++ b/src/cmd/internal/gc/gen.go
@@ -61,7 +61,7 @@
 			n.Stackparam = Nod(OPARAM, n, nil)
 
 			n.Stackparam.Type = n.Type
-			n.Stackparam.Addable = 1
+			n.Stackparam.Addable = true
 			if n.Xoffset == BADWIDTH {
 				Fatal("addrescapes before param assignment")
 			}
@@ -73,7 +73,7 @@
 		case PAUTO:
 			n.Class |= PHEAP
 
-			n.Addable = 0
+			n.Addable = false
 			n.Ullman = 2
 			n.Xoffset = 0
 
@@ -332,7 +332,7 @@
 	var z Node
 	z.Op = OLITERAL
 	z.Type = n.Type
-	z.Addable = 1
+	z.Addable = true
 
 	switch Simtype[n.Type.Etype] {
 	case TCOMPLEX64, TCOMPLEX128:
@@ -749,7 +749,7 @@
 	s.Def = n
 	n.Type = t
 	n.Class = PAUTO
-	n.Addable = 1
+	n.Addable = true
 	n.Ullman = 1
 	n.Esc = EscNever
 	n.Curfn = Curfn
@@ -1373,7 +1373,7 @@
 }
 
 func cadable(n *Node) bool {
-	if n.Addable == 0 {
+	if !n.Addable {
 		// dont know how it happens,
 		// but it does
 		return false
diff --git a/src/cmd/internal/gc/go.y b/src/cmd/internal/gc/go.y
index 31bebf3..aa2eac1 100644
--- a/src/cmd/internal/gc/go.y
+++ b/src/cmd/internal/gc/go.y
@@ -618,7 +618,7 @@
 	{
 		$$ = Nod(ORANGE, nil, $4);
 		$$.List = $1;
-		$$.Colas = 1;
+		$$.Colas = true;
 		colasdefn($1, $$);
 	}
 |	LRANGE expr
@@ -631,7 +631,7 @@
 	osimple_stmt ';' osimple_stmt ';' osimple_stmt
 	{
 		// init ; test ; incr
-		if $5 != nil && $5.Colas != 0 {
+		if $5 != nil && $5.Colas {
 			Yyerror("cannot declare in the for-increment");
 		}
 		$$ = Nod(OFOR, nil, nil);
diff --git a/src/cmd/internal/gc/gsubr.go b/src/cmd/internal/gc/gsubr.go
index d54f905..6ca8c75 100644
--- a/src/cmd/internal/gc/gsubr.go
+++ b/src/cmd/internal/gc/gsubr.go
@@ -133,7 +133,7 @@
 
 	*n = Node{}
 	n.Op = OREGISTER
-	n.Addable = 1
+	n.Addable = true
 	ullmancalc(n)
 	n.Val.U.Reg = int16(r)
 	n.Type = t
@@ -361,7 +361,7 @@
 		if s == nil {
 			s = Lookup(".noname")
 		}
-		if n.Method != 0 {
+		if n.Method {
 			if n.Type != nil {
 				if n.Type.Sym != nil {
 					if n.Type.Sym.Pkg != nil {
@@ -520,7 +520,7 @@
 			Fatal("nodarg: offset not computed for %v", Tconv(t, 0))
 		}
 		n.Xoffset = first.Width
-		n.Addable = 1
+		n.Addable = true
 		goto fp
 	}
 
@@ -546,7 +546,7 @@
 		Fatal("nodarg: offset not computed for %v", Tconv(t, 0))
 	}
 	n.Xoffset = t.Width
-	n.Addable = 1
+	n.Addable = true
 	n.Orig = t.Nname
 
 	// Rewrite argument named _ to __,
diff --git a/src/cmd/internal/gc/order.go b/src/cmd/internal/gc/order.go
index 9dc9b69..ec74463 100644
--- a/src/cmd/internal/gc/order.go
+++ b/src/cmd/internal/gc/order.go
@@ -770,7 +770,7 @@
 				// declaration (and possible allocation) until inside the case body.
 				// Delete the ODCL nodes here and recreate them inside the body below.
 				case OSELRECV, OSELRECV2:
-					if r.Colas != 0 {
+					if r.Colas {
 						t = r.Ninit
 						if t != nil && t.N.Op == ODCL && t.N.Left == r.Left {
 							t = t.Next
@@ -814,7 +814,7 @@
 						// the conversion happens in the OAS instead.
 						tmp1 = r.Left
 
-						if r.Colas != 0 {
+						if r.Colas {
 							tmp2 = Nod(ODCL, tmp1, nil)
 							typecheck(&tmp2, Etop)
 							l.N.Ninit = list(l.N.Ninit, tmp2)
@@ -831,7 +831,7 @@
 					}
 					if r.Ntest != nil {
 						tmp1 = r.Ntest
-						if r.Colas != 0 {
+						if r.Colas {
 							tmp2 = Nod(ODCL, tmp1, nil)
 							typecheck(&tmp2, Etop)
 							l.N.Ninit = list(l.N.Ninit, tmp2)
diff --git a/src/cmd/internal/gc/pgen.go b/src/cmd/internal/gc/pgen.go
index b6c9f30..4100c20 100644
--- a/src/cmd/internal/gc/pgen.go
+++ b/src/cmd/internal/gc/pgen.go
@@ -331,7 +331,7 @@
 		Fatal("bad checknil")
 	}
 
-	if ((Thearch.Thechar == '5' || Thearch.Thechar == '7' || Thearch.Thechar == '9') && n.Op != OREGISTER) || n.Addable == 0 || n.Op == OLITERAL {
+	if ((Thearch.Thechar == '5' || Thearch.Thechar == '7' || Thearch.Thechar == '9') && n.Op != OREGISTER) || !n.Addable || n.Op == OLITERAL {
 		var reg Node
 		Regalloc(&reg, Types[Tptr], n)
 		Cgen(n, &reg)
diff --git a/src/cmd/internal/gc/reflect.go b/src/cmd/internal/gc/reflect.go
index bd5be0f..77504fa 100644
--- a/src/cmd/internal/gc/reflect.go
+++ b/src/cmd/internal/gc/reflect.go
@@ -882,7 +882,7 @@
 		n := Nod(ONAME, nil, nil)
 		n.Sym = s
 		n.Type = Types[TUINT8]
-		n.Addable = 1
+		n.Addable = true
 		n.Ullman = 1
 		n.Class = PEXTERN
 		n.Xoffset = 0
@@ -899,7 +899,7 @@
 	s := typenamesym(t)
 	n := Nod(OADDR, s.Def, nil)
 	n.Type = Ptrto(s.Def.Type)
-	n.Addable = 1
+	n.Addable = true
 	n.Ullman = 2
 	n.Typecheck = 1
 	return n
diff --git a/src/cmd/internal/gc/sinit.go b/src/cmd/internal/gc/sinit.go
index f716736..96743b8 100644
--- a/src/cmd/internal/gc/sinit.go
+++ b/src/cmd/internal/gc/sinit.go
@@ -529,7 +529,7 @@
 	if n.Op != ONAME {
 		return false
 	}
-	if n.Addable == 0 {
+	if !n.Addable {
 		return false
 	}
 	if n.Class&PHEAP != 0 {
@@ -1239,7 +1239,7 @@
 	switch n.Op {
 	case ONAME:
 		*nam = *n
-		return n.Addable != 0
+		return n.Addable
 
 	case ODOT:
 		if !stataddr(nam, n.Left) {
diff --git a/src/cmd/internal/gc/subr.go b/src/cmd/internal/gc/subr.go
index 5505fe3..f01cda1 100644
--- a/src/cmd/internal/gc/subr.go
+++ b/src/cmd/internal/gc/subr.go
@@ -669,7 +669,7 @@
 
 func Nodintconst(v int64) *Node {
 	c := Nod(OLITERAL, nil, nil)
-	c.Addable = 1
+	c.Addable = true
 	c.Val.U.Xval = new(Mpint)
 	Mpmovecfix(c.Val.U.Xval, v)
 	c.Val.Ctype = CTINT
@@ -680,7 +680,7 @@
 
 func nodfltconst(v *Mpflt) *Node {
 	c := Nod(OLITERAL, nil, nil)
-	c.Addable = 1
+	c.Addable = true
 	c.Val.U.Fval = newMpflt()
 	mpmovefltflt(c.Val.U.Fval, v)
 	c.Val.Ctype = CTFLT
@@ -692,7 +692,7 @@
 func Nodconst(n *Node, t *Type, v int64) {
 	*n = Node{}
 	n.Op = OLITERAL
-	n.Addable = 1
+	n.Addable = true
 	ullmancalc(n)
 	n.Val.U.Xval = new(Mpint)
 	Mpmovecfix(n.Val.U.Xval, v)
@@ -2572,7 +2572,7 @@
 		ni := newname(Lookup("i"))
 		ni.Type = Types[TINT]
 		n.List = list1(ni)
-		n.Colas = 1
+		n.Colas = true
 		colasdefn(n.List, n)
 		ni = n.List.N
 
@@ -2824,7 +2824,7 @@
 		ni := newname(Lookup("i"))
 		ni.Type = Types[TINT]
 		nrange.List = list1(ni)
-		nrange.Colas = 1
+		nrange.Colas = true
 		colasdefn(nrange.List, nrange)
 		ni = nrange.List.N
 
diff --git a/src/cmd/internal/gc/syntax.go b/src/cmd/internal/gc/syntax.go
index 671a624..736c7af 100644
--- a/src/cmd/internal/gc/syntax.go
+++ b/src/cmd/internal/gc/syntax.go
@@ -26,13 +26,13 @@
 	Op          uint8
 	Nointerface bool
 	Ullman      uint8 // sethi/ullman number
-	Addable     uint8 // type of addressability - 0 is not addressable
+	Addable     bool  // addressable
 	Etype       uint8 // op for OASOP, etype for OTYPE, exclam for export
 	Bounded     bool  // bounds check unnecessary
 	Class       uint8 // PPARAM, PAUTO, PEXTERN, etc
-	Method      uint8 // OCALLMETH name
+	Method      bool  // OCALLMETH is direct method call
 	Embedded    uint8 // ODCLFIELD embedded type
-	Colas       uint8 // OAS resulting from :=
+	Colas       bool  // OAS resulting from :=
 	Diag        uint8 // already printed error about this
 	Noescape    bool  // func arguments do not escape; TODO(rsc): move Noescape to Func struct (see CL 7360)
 	Walkdef     uint8
diff --git a/src/cmd/internal/gc/walk.go b/src/cmd/internal/gc/walk.go
index c845f78..bf91116 100644
--- a/src/cmd/internal/gc/walk.go
+++ b/src/cmd/internal/gc/walk.go
@@ -564,16 +564,16 @@
 		goto ret
 
 	case OLITERAL:
-		n.Addable = 1
+		n.Addable = true
 		goto ret
 
 	case OCLOSUREVAR, OCFUNC:
-		n.Addable = 1
+		n.Addable = true
 		goto ret
 
 	case ONAME:
 		if n.Class&PHEAP == 0 && n.Class != PPARAMREF {
-			n.Addable = 1
+			n.Addable = true
 		}
 		goto ret
 
@@ -975,7 +975,7 @@
 				l := Nod(ONAME, nil, nil)
 				l.Sym = sym
 				l.Type = Ptrto(Types[TUINT8])
-				l.Addable = 1
+				l.Addable = true
 				l.Class = PEXTERN
 				l.Xoffset = 0
 				sym.Def = l
@@ -983,7 +983,7 @@
 			}
 
 			l := Nod(OADDR, sym.Def, nil)
-			l.Addable = 1
+			l.Addable = true
 			ll = list(ll, l)
 
 			if isdirectiface(n.Left.Type) {
diff --git a/src/cmd/internal/gc/y.go b/src/cmd/internal/gc/y.go
index cfa4ec6..c952e65 100644
--- a/src/cmd/internal/gc/y.go
+++ b/src/cmd/internal/gc/y.go
@@ -1733,7 +1733,7 @@
 		{
 			yyVAL.node = Nod(ORANGE, nil, yyDollar[4].node)
 			yyVAL.node.List = yyDollar[1].list
-			yyVAL.node.Colas = 1
+			yyVAL.node.Colas = true
 			colasdefn(yyDollar[1].list, yyVAL.node)
 		}
 	case 69:
@@ -1748,7 +1748,7 @@
 		//line go.y:632
 		{
 			// init ; test ; incr
-			if yyDollar[5].node != nil && yyDollar[5].node.Colas != 0 {
+			if yyDollar[5].node != nil && yyDollar[5].node.Colas {
 				Yyerror("cannot declare in the for-increment")
 			}
 			yyVAL.node = Nod(OFOR, nil, nil)