diff --git a/src/libcore/num/f32.rs b/src/libcore/num/f32.rs
index d2334943b3d1..f8a85e788e9e 100644
--- a/src/libcore/num/f32.rs
+++ b/src/libcore/num/f32.rs
@@ -22,12 +22,12 @@ use num::Float;
 use num::FpCategory as Fp;
 use option::Option;
 
-#[stable]
+#[unstable = "pending integer conventions"]
 pub const RADIX: uint = 2u;
 
-#[stable]
+#[unstable = "pending integer conventions"]
 pub const MANTISSA_DIGITS: uint = 24u;
-#[stable]
+#[unstable = "pending integer conventions"]
 pub const DIGITS: uint = 6u;
 
 #[stable]
@@ -43,14 +43,14 @@ pub const MIN_POS_VALUE: f32 = 1.17549435e-38_f32;
 #[stable]
 pub const MAX_VALUE: f32 = 3.40282347e+38_f32;
 
-#[stable]
+#[unstable = "pending integer conventions"]
 pub const MIN_EXP: int = -125;
-#[stable]
+#[unstable = "pending integer conventions"]
 pub const MAX_EXP: int = 128;
 
-#[stable]
+#[unstable = "pending integer conventions"]
 pub const MIN_10_EXP: int = -37;
-#[stable]
+#[unstable = "pending integer conventions"]
 pub const MAX_10_EXP: int = 38;
 
 #[stable]
diff --git a/src/libcore/num/f64.rs b/src/libcore/num/f64.rs
index 95cc5f224090..840428179cdc 100644
--- a/src/libcore/num/f64.rs
+++ b/src/libcore/num/f64.rs
@@ -26,12 +26,11 @@ use option::Option;
 // constants are implemented in favour of referencing the respective
 // members of `Bounded` and `Float`.
 
-#[stable]
+#[unstable = "pending integer conventions"]
 pub const RADIX: uint = 2u;
 
-#[stable]
 pub const MANTISSA_DIGITS: uint = 53u;
-#[stable]
+#[unstable = "pending integer conventions"]
 pub const DIGITS: uint = 15u;
 
 #[stable]
@@ -47,14 +46,14 @@ pub const MIN_POS_VALUE: f64 = 2.2250738585072014e-308_f64;
 #[stable]
 pub const MAX_VALUE: f64 = 1.7976931348623157e+308_f64;
 
-#[stable]
+#[unstable = "pending integer conventions"]
 pub const MIN_EXP: int = -1021;
-#[stable]
+#[unstable = "pending integer conventions"]
 pub const MAX_EXP: int = 1024;
 
-#[stable]
+#[unstable = "pending integer conventions"]
 pub const MIN_10_EXP: int = -307;
-#[stable]
+#[unstable = "pending integer conventions"]
 pub const MAX_10_EXP: int = 308;
 
 #[stable]