diff --git a/cl/_testdata/builtin/in.go b/cl/_testdata/builtin/in.go
new file mode 100644
index 00000000..3a3acbd5
--- /dev/null
+++ b/cl/_testdata/builtin/in.go
@@ -0,0 +1,11 @@
+package main
+
+var a int64 = 1<<63 - 1
+var b int64 = -1 << 63
+var c uint64 = 1<<64 - 1
+
+func main() {
+	var a = []int{1, 2, 3, 4}
+	_ = len(a)
+	_ = len([]int{1, 2, 3, 4})
+}
diff --git a/cl/_testdata/builtin/out.ll b/cl/_testdata/builtin/out.ll
new file mode 100644
index 00000000..d284826e
--- /dev/null
+++ b/cl/_testdata/builtin/out.ll
@@ -0,0 +1,59 @@
+; ModuleID = 'main'
+source_filename = "main"
+
+%"github.com/goplus/llgo/internal/runtime.Slice" = type { ptr, i64, i64 }
+
+@main.a = global ptr null
+@main.b = global ptr null
+@main.c = global ptr null
+@"main.init$guard" = global ptr null
+
+define void @main.init() {
+_llgo_0:
+  %0 = load i1, ptr @"main.init$guard", align 1
+  br i1 %0, label %_llgo_2, label %_llgo_1
+
+_llgo_1:                                          ; preds = %_llgo_0
+  store i1 true, ptr @"main.init$guard", align 1
+  store i64 9223372036854775807, ptr @main.a, align 4
+  store i64 -9223372036854775808, ptr @main.b, align 4
+  store i64 -1, ptr @main.c, align 4
+  br label %_llgo_2
+
+_llgo_2:                                          ; preds = %_llgo_1, %_llgo_0
+  ret void
+}
+
+define void @main() {
+_llgo_0:
+  call void @main.init()
+  %0 = call ptr @"github.com/goplus/llgo/internal/runtime.Alloc"(i64 16)
+  %1 = getelementptr inbounds i64, ptr %0, i64 0
+  store i64 1, ptr %1, align 4
+  %2 = getelementptr inbounds i64, ptr %0, i64 1
+  store i64 2, ptr %2, align 4
+  %3 = getelementptr inbounds i64, ptr %0, i64 2
+  store i64 3, ptr %3, align 4
+  %4 = getelementptr inbounds i64, ptr %0, i64 3
+  store i64 4, ptr %4, align 4
+  %5 = call %"github.com/goplus/llgo/internal/runtime.Slice" @"github.com/goplus/llgo/internal/runtime.NewSlice"(i64 4, i64 4)
+  %6 = call i64 @"github.com/goplus/llgo/internal/runtime.SliceLen"(%"github.com/goplus/llgo/internal/runtime.Slice" %5)
+  %7 = call ptr @"github.com/goplus/llgo/internal/runtime.Alloc"(i64 16)
+  %8 = getelementptr inbounds i64, ptr %7, i64 0
+  store i64 1, ptr %8, align 4
+  %9 = getelementptr inbounds i64, ptr %7, i64 1
+  store i64 2, ptr %9, align 4
+  %10 = getelementptr inbounds i64, ptr %7, i64 2
+  store i64 3, ptr %10, align 4
+  %11 = getelementptr inbounds i64, ptr %7, i64 3
+  store i64 4, ptr %11, align 4
+  %12 = call %"github.com/goplus/llgo/internal/runtime.Slice" @"github.com/goplus/llgo/internal/runtime.NewSlice"(i64 4, i64 4)
+  %13 = call i64 @"github.com/goplus/llgo/internal/runtime.SliceLen"(%"github.com/goplus/llgo/internal/runtime.Slice" %12)
+  ret void
+}
+
+declare ptr @"github.com/goplus/llgo/internal/runtime.Alloc"(i64)
+
+declare %"github.com/goplus/llgo/internal/runtime.Slice" @"github.com/goplus/llgo/internal/runtime.NewSlice"(ptr, i64, i64)
+
+declare i64 @"github.com/goplus/llgo/internal/runtime.SliceLen"(%"github.com/goplus/llgo/internal/runtime.Slice")
diff --git a/ssa/expr.go b/ssa/expr.go
index c9f17005..476a276f 100644
--- a/ssa/expr.go
+++ b/ssa/expr.go
@@ -136,16 +136,14 @@ func (b Builder) Const(v constant.Value, typ Type) Expr {
 		switch {
 		case kind == types.Bool:
 			return prog.BoolVal(constant.BoolVal(v))
-		case kind >= types.Int && kind <= types.Uintptr:
+		case kind >= types.Int && kind <= types.Int64:
 			if v, exact := constant.Int64Val(v); exact {
 				return prog.IntVal(uint64(v), typ)
 			}
-			panic("todo")
-			/*
-				if v, exact := constant.Uint64Val(v); exact {
-					return prog.IntVal(v, typ)
-				}
-			*/
+		case kind >= types.Uint && kind <= types.Uintptr:
+			if v, exact := constant.Uint64Val(v); exact {
+				return prog.IntVal(v, typ)
+			}
 		case kind == types.Float32 || kind == types.Float64:
 			if v, exact := constant.Float64Val(v); exact {
 				return prog.FloatVal(v, typ)
@@ -460,7 +458,8 @@ func (b Builder) Slice(x, low, high, max Expr) (ret Expr) {
 			ret.Type = prog.Type(types.NewSlice(te.Elem()))
 			if low.IsNil() && high.IsNil() && max.IsNil() {
 				n := prog.Val(int(te.Len()))
-				return b.InlineCall(pkg.rtFunc("NewSlice"), n, n)
+				ret.impl = b.InlineCall(pkg.rtFunc("NewSlice"), n, n).impl
+				return ret
 			}
 		}
 	}