diff --git a/build.rs b/build.rs
index 3f1b971..72f722f 100644
--- a/build.rs
+++ b/build.rs
@@ -6,6 +6,7 @@ use std::{
 };
 fn main() {
     let mut cmake_conf = cmake::Config::new("open_jtalk");
+    cmake_conf.define("FETCHCONTENT_SOURCE_DIR_OPENJTALK", "@openjtalk_src@");
     let target = env::var("TARGET").unwrap();
     let mut include_dirs: Vec<PathBuf> = Vec::new();
     let cmake_conf = if target.starts_with("i686") {
