diff --git a/src/bootstrap/install.rs b/src/bootstrap/install.rs
index 4b05cac1ce6..d71fdb8a30c 100644
--- a/src/bootstrap/install.rs
+++ b/src/bootstrap/install.rs
@@ -72,7 +72,9 @@ fn install_sh(
     let bindir_default = PathBuf::from("bin");
     let libdir_default = PathBuf::from("lib");
     let mandir_default = datadir_default.join("man");
-    let prefix = build.config.prefix.as_ref().unwrap_or(&prefix_default);
+    let prefix = build.config.prefix.as_ref().map_or(prefix_default, |p| {
+        fs::canonicalize(p).expect(&format!("could not canonicalize {}", p.display()))
+    });
     let sysconfdir = build.config.sysconfdir.as_ref().unwrap_or(&sysconfdir_default);
     let datadir = build.config.datadir.as_ref().unwrap_or(&datadir_default);
     let docdir = build.config.docdir.as_ref().unwrap_or(&docdir_default);