diff --git a/src/libstd/bigint.rs b/src/libstd/bigint.rs
index d64bc368790a..af273a706b57 100644
--- a/src/libstd/bigint.rs
+++ b/src/libstd/bigint.rs
@@ -851,7 +851,8 @@ mod biguint_tests {
     }
 
     #[test]
-    #[ignore]
+    #[ignore(cfg(target_arch = "x86"))]
+    #[ignore(cfg(target_arch = "arm"))]
     fn test_shl() {
         fn check(v: ~[BigDigit], shift: uint, ans: ~[BigDigit]) {
             assert BigUint::new(v) << shift == BigUint::new(ans);
@@ -869,7 +870,8 @@ mod biguint_tests {
     }
 
     #[test]
-    #[ignore]
+    #[ignore(cfg(target_arch = "x86"))]
+    #[ignore(cfg(target_arch = "arm"))]
     fn test_shr() {
         fn check(v: ~[BigDigit], shift: uint, ans: ~[BigDigit]) {
             assert BigUint::new(v) >> shift == BigUint::new(ans);
@@ -1089,7 +1091,8 @@ mod biguint_tests {
     }
 
     #[test]
-    #[ignore]
+    #[ignore(cfg(target_arch = "x86"))]
+    #[ignore(cfg(target_arch = "arm"))]
     fn test_to_str_radix() {
         for to_str_pairs().each |num_pair| {
             let &(n, rs) = num_pair;
@@ -1101,7 +1104,8 @@ mod biguint_tests {
     }
 
     #[test]
-    #[ignore]
+    #[ignore(cfg(target_arch = "x86"))]
+    #[ignore(cfg(target_arch = "arm"))]
     fn test_from_str_radix() {
         for to_str_pairs().each |num_pair| {
             let &(n, rs) = num_pair;