diff --git a/library/compiler-builtins/build.rs b/library/compiler-builtins/build.rs
index 6f2cc76a9617..f5ada024f41e 100644
--- a/library/compiler-builtins/build.rs
+++ b/library/compiler-builtins/build.rs
@@ -17,9 +17,9 @@ fn main() {
         return;
     }
 
-    // Forcibly enable memory intrinsics on wasm32 as we don't have a libc to
+    // Forcibly enable memory intrinsics on wasm32 & SGX as we don't have a libc to
     // provide them.
-    if target.contains("wasm32") {
+    if target.contains("wasm32") || target.contains("sgx") {
         println!("cargo:rustc-cfg=feature=\"mem\"");
     }
 
diff --git a/library/compiler-builtins/src/lib.rs b/library/compiler-builtins/src/lib.rs
index 9f1dd15120c0..9bb38f39aa2f 100644
--- a/library/compiler-builtins/src/lib.rs
+++ b/library/compiler-builtins/src/lib.rs
@@ -48,7 +48,8 @@ pub mod int;
 pub mod float;
 
 #[cfg(any(all(target_arch = "wasm32", target_os = "unknown"),
-          all(target_arch = "arm", target_os = "none")))]
+          all(target_arch = "arm", target_os = "none"),
+          target_env = "sgx"))]
 pub mod math;
 pub mod mem;
 
diff --git a/library/compiler-builtins/src/math.rs b/library/compiler-builtins/src/math.rs
index 9db7a0aa3d6b..c37243504b1b 100644
--- a/library/compiler-builtins/src/math.rs
+++ b/library/compiler-builtins/src/math.rs
@@ -15,7 +15,7 @@ macro_rules! no_mangle {
 }
 
 // only for the wasm32-unknown-unknown target
-#[cfg(all(target_arch = "wasm32", target_os = "unknown"))]
+#[cfg(any(all(target_arch = "wasm32", target_os = "unknown"), target_env = "sgx"))]
 no_mangle! {
     fn acos(x: f64) -> f64;
     fn asin(x: f64) -> f64;