diff --git a/vlib/builtin/int.v b/vlib/builtin/int.v
index e5df7d79c0..1bd004cb7c 100644
--- a/vlib/builtin/int.v
+++ b/vlib/builtin/int.v
@@ -156,14 +156,18 @@ pub fn (n int) hex() string {
 pub fn (n i64) hex() string {
 	len := if n >= 0 { n.str().len + 3 } else { 19 }
 	hex := malloc(len)
-	count := C.sprintf(charptr(hex), '0x%'C.PRIx64, n)
+	// TODO
+	//count := C.sprintf(charptr(hex), '0x%'C.PRIx64, n)
+	count := C.sprintf(charptr(hex), '0x%llx', n)
 	return tos(hex, count)
 }
 
 pub fn (n u64) hex() string {
 	len := if n > 0 { n.str().len + 3 } else { 19 }
 	hex := malloc(len)
-	count := C.sprintf(charptr(hex), '0x%'C.PRIx64, n)
+	//count := C.sprintf(charptr(hex), '0x%'C.PRIx64, n)
+	count := C.sprintf(charptr(hex), '0x%llx', n)
+	//count := C.sprintf(charptr(hex), '0x%lx', n)
 	return tos(hex, count)
 }
 
diff --git a/vlib/v/ast/ast.v b/vlib/v/ast/ast.v
index 822b0cea1f..be8a813429 100644
--- a/vlib/v/ast/ast.v
+++ b/vlib/v/ast/ast.v
@@ -11,7 +11,8 @@ import (
 pub type Expr = InfixExpr | IfExpr | StringLiteral | IntegerLiteral | CharLiteral | 	
 FloatLiteral | Ident | CallExpr | BoolLiteral | StructInit | ArrayInit | SelectorExpr | PostfixExpr | 	
 AssignExpr | PrefixExpr | MethodCallExpr | IndexExpr | RangeExpr | MatchExpr | 	
-CastExpr | EnumVal | Assoc | SizeOf | None | MapInit | IfGuardExpr | ParExpr | OrExpr
+CastExpr | EnumVal | Assoc | SizeOf | None | MapInit | IfGuardExpr | ParExpr | OrExpr | 	
+ConcatExpr
 
 pub type Stmt = VarDecl | GlobalDecl | FnDecl | Return | Module | Import | ExprStmt | 	
 ForStmt | StructDecl | ForCStmt | ForInStmt | CompIf | ConstDecl | Attr | BranchStmt | 	
@@ -535,6 +536,11 @@ pub:
 	text string
 }
 
+pub struct ConcatExpr {
+pub:
+	vals []Expr
+}
+
 pub struct None {
 pub:
 	foo int // todo
diff --git a/vlib/v/checker/checker.v b/vlib/v/checker/checker.v
index d53debf25a..67ab421a2d 100644
--- a/vlib/v/checker/checker.v
+++ b/vlib/v/checker/checker.v
@@ -439,11 +439,16 @@ fn (c mut Checker) stmt(node ast.Stmt) {
 			it.typ = typ
 		}
 		else {
+			println('checker.stmt(): unhandled node')
+		}
+		/*
+			println('1')
 			node_name := typeof(node)
-			if !(node_name) in c.unhandled_stmts {
+			println('2')
+			if !(node_name in c.unhandled_stmts) {
 				c.unhandled_stmts << node_name
 			}
-		}
+			*/
 	}
 }