cgen: fix error for printing aliases of multi fixed array (#14348)

vlib/v/gen/c/assign.v

@@ -18,6 +18,9 @@ fn (mut g Gen) gen_assign_stmt(node_ ast.AssignStmt) {
 	mut return_type := ast.void_type
 	is_decl := node.op == .decl_assign
 	g.assign_op = node.op
+	defer {
+		g.assign_op = .unknown
+	}
 	op := if is_decl { token.Kind.assign } else { node.op }
 	right_expr := node.right[0]
 	match right_expr {

vlib/v/gen/c/cgen.v

@@ -3883,6 +3883,9 @@ fn (mut g Gen) cast_expr(node ast.CastExpr) {
 		g.expr(node.expr)
 		g.write('))')
 	} else if sym.kind == .alias && g.table.final_sym(node.typ).kind == .array_fixed {
+		if node.expr is ast.ArrayInit && g.assign_op != .decl_assign {
+			g.write('(${g.typ(node.expr.typ)})')
+		}
 		g.expr(node.expr)
 	} else if node.expr_type == ast.bool_type && node.typ.is_int() {
 		styp := g.typ(node.typ)

vlib/v/tests/inout/printing_aliases_of_multi_fixed_array.out

@@ -0,0 +1,2 @@
+Mat([[1, 2], [3, 4]])
+Mat([[1, 2], [3, 4]])

vlib/v/tests/inout/printing_aliases_of_multi_fixed_array.vv

@@ -0,0 +1,7 @@
+type Mat = [2][2]int
+
+fn main() {
+	a := Mat([[1, 2]!, [3, 4]!]!)
+	println(a)
+	println(Mat([[1, 2]!, [3, 4]!]!))
+}