Don't check names in non-declaration assignment statements.
diff --git a/lint.go b/lint.go
index dffff3f..b63914b 100644
--- a/lint.go
+++ b/lint.go
@@ -270,6 +270,9 @@
 	f.walk(func(node ast.Node) bool {
 		switch v := node.(type) {
 		case *ast.AssignStmt:
+			if v.Tok == token.ASSIGN {
+				return true
+			}
 			for _, exp := range v.Lhs {
 				if id, ok := exp.(*ast.Ident); ok {
 					check(id, "var")
diff --git a/testdata/names.go b/testdata/names.go
index e923980..25f5901 100644
--- a/testdata/names.go
+++ b/testdata/names.go
@@ -14,6 +14,9 @@
 
 func f_it() { // MATCH /underscore.*func.*f_it/
 	more_underscore := 4 // MATCH /underscore.*var.*more_underscore/
+	if true {
+		more_underscore = 7 // should be okay
+	}
 
 	x := foo_proto.Blah{} // should be okay
 }