Use pointers instead of values

regex/compile.go

@@ -987,7 +987,8 @@ func thompson(re []postfixNode) (Reg, error) {
 		if c.nodetype == charclassNode { // A Character class consists of all the nodes in it, alternated
 			// Map the list of nodes to a list of states, each state containing the contents of a specific node
 			states := funcMap(c.nodeContents, func(node postfixNode) *nfaState {
-				s := newState()
+				s := &nfaState{}
+				s.output = append(s.output, s)
 				nodeContents := node.contents
 				if caseInsensitive {
 					nodeContents = slices.Concat(funcMap(nodeContents, func(r rune) []rune {
@@ -1001,7 +1002,7 @@ func thompson(re []postfixNode) (Reg, error) {
 						return n.contents
 					})...)
 				}
-				return &s
+				return s
 			})
 			// Reduce the list of states down to a single state by alternating them
 			toAdd := funcReduce(states, func(s1 *nfaState, s2 *nfaState) *nfaState {