diff --git a/libm b/libm
index 1f7b8eb6..add735e3 160000
--- a/libm
+++ b/libm
@@ -1 +1 @@
-Subproject commit 1f7b8eb61cab5f62ec93d2343432bebd1ada30f2
+Subproject commit add735e30df2ba780fb76187f43163dedcd96fa7
diff --git a/src/math.rs b/src/math.rs
index 14a65395..c3b9788e 100644
--- a/src/math.rs
+++ b/src/math.rs
@@ -63,6 +63,8 @@ no_mangle! {
     fn tanhf(n: f32) -> f32;
     fn ldexp(f: f64, n: i32) -> f64;
     fn ldexpf(f: f32, n: i32) -> f32;
+    fn tgamma(x: f64) -> f64;
+    fn tgammaf(x: f32) -> f32;
 }
 
 #[cfg(any(