diff --git a/src/libcore/num/f32.rs b/src/libcore/num/f32.rs
index 404f1a82de5d..6233f8c2a61b 100644
--- a/src/libcore/num/f32.rs
+++ b/src/libcore/num/f32.rs
@@ -10,12 +10,9 @@
 
 //! Operations and constants for `f32`
 
-use cmath;
-use libc::{c_float, c_int};
 use num::strconv;
 use num;
 use option::Option;
-use unstable::intrinsics::floorf32;
 use from_str;
 use to_str;
 
@@ -24,79 +21,93 @@ use to_str;
 
 pub use cmath::c_float_targ_consts::*;
 
+// An inner module is required to get the #[inline(always)] attribute on the
+// functions.
+pub use self::delegated::*;
+
 macro_rules! delegate(
     (
-        fn $name:ident(
-            $(
-                $arg:ident : $arg_ty:ty
-            ),*
-        ) -> $rv:ty = $bound_name:path
+        $(
+            fn $name:ident(
+                $(
+                    $arg:ident : $arg_ty:ty
+                ),*
+            ) -> $rv:ty = $bound_name:path
+        ),*
     ) => (
-        pub fn $name($( $arg : $arg_ty ),*) -> $rv {
-            unsafe {
-                $bound_name($( $arg ),*)
-            }
+        mod delegated {
+            use cmath::c_float_utils;
+            use libc::{c_float, c_int};
+            use unstable::intrinsics;
+
+            $(
+                #[inline(always)]
+                pub fn $name($( $arg : $arg_ty ),*) -> $rv {
+                    unsafe {
+                        $bound_name($( $arg ),*)
+                    }
+                }
+            )*
         }
     )
 )
 
-delegate!(fn acos(n: c_float) -> c_float = cmath::c_float_utils::acos)
-delegate!(fn asin(n: c_float) -> c_float = cmath::c_float_utils::asin)
-delegate!(fn atan(n: c_float) -> c_float = cmath::c_float_utils::atan)
-delegate!(fn atan2(a: c_float, b: c_float) -> c_float =
-    cmath::c_float_utils::atan2)
-delegate!(fn cbrt(n: c_float) -> c_float = cmath::c_float_utils::cbrt)
-delegate!(fn ceil(n: c_float) -> c_float = cmath::c_float_utils::ceil)
-delegate!(fn copysign(x: c_float, y: c_float) -> c_float =
-    cmath::c_float_utils::copysign)
-delegate!(fn cos(n: c_float) -> c_float = cmath::c_float_utils::cos)
-delegate!(fn cosh(n: c_float) -> c_float = cmath::c_float_utils::cosh)
-delegate!(fn erf(n: c_float) -> c_float = cmath::c_float_utils::erf)
-delegate!(fn erfc(n: c_float) -> c_float = cmath::c_float_utils::erfc)
-delegate!(fn exp(n: c_float) -> c_float = cmath::c_float_utils::exp)
-delegate!(fn expm1(n: c_float) -> c_float = cmath::c_float_utils::expm1)
-delegate!(fn exp2(n: c_float) -> c_float = cmath::c_float_utils::exp2)
-delegate!(fn abs(n: c_float) -> c_float = cmath::c_float_utils::abs)
-delegate!(fn abs_sub(a: c_float, b: c_float) -> c_float =
-    cmath::c_float_utils::abs_sub)
-delegate!(fn mul_add(a: c_float, b: c_float, c: c_float) -> c_float =
-    cmath::c_float_utils::mul_add)
-delegate!(fn fmax(a: c_float, b: c_float) -> c_float =
-    cmath::c_float_utils::fmax)
-delegate!(fn fmin(a: c_float, b: c_float) -> c_float =
-    cmath::c_float_utils::fmin)
-delegate!(fn nextafter(x: c_float, y: c_float) -> c_float =
-    cmath::c_float_utils::nextafter)
-delegate!(fn frexp(n: c_float, value: &mut c_int) -> c_float =
-    cmath::c_float_utils::frexp)
-delegate!(fn hypot(x: c_float, y: c_float) -> c_float =
-    cmath::c_float_utils::hypot)
-delegate!(fn ldexp(x: c_float, n: c_int) -> c_float =
-    cmath::c_float_utils::ldexp)
-delegate!(fn lgamma(n: c_float, sign: &mut c_int) -> c_float =
-    cmath::c_float_utils::lgamma)
-delegate!(fn ln(n: c_float) -> c_float = cmath::c_float_utils::ln)
-delegate!(fn log_radix(n: c_float) -> c_float =
-    cmath::c_float_utils::log_radix)
-delegate!(fn ln1p(n: c_float) -> c_float = cmath::c_float_utils::ln1p)
-delegate!(fn log10(n: c_float) -> c_float = cmath::c_float_utils::log10)
-delegate!(fn log2(n: c_float) -> c_float = cmath::c_float_utils::log2)
-delegate!(fn ilog_radix(n: c_float) -> c_int =
-    cmath::c_float_utils::ilog_radix)
-delegate!(fn modf(n: c_float, iptr: &mut c_float) -> c_float =
-    cmath::c_float_utils::modf)
-delegate!(fn pow(n: c_float, e: c_float) -> c_float =
-    cmath::c_float_utils::pow)
-delegate!(fn round(n: c_float) -> c_float = cmath::c_float_utils::round)
-delegate!(fn ldexp_radix(n: c_float, i: c_int) -> c_float =
-    cmath::c_float_utils::ldexp_radix)
-delegate!(fn sin(n: c_float) -> c_float = cmath::c_float_utils::sin)
-delegate!(fn sinh(n: c_float) -> c_float = cmath::c_float_utils::sinh)
-delegate!(fn sqrt(n: c_float) -> c_float = cmath::c_float_utils::sqrt)
-delegate!(fn tan(n: c_float) -> c_float = cmath::c_float_utils::tan)
-delegate!(fn tanh(n: c_float) -> c_float = cmath::c_float_utils::tanh)
-delegate!(fn tgamma(n: c_float) -> c_float = cmath::c_float_utils::tgamma)
-delegate!(fn trunc(n: c_float) -> c_float = cmath::c_float_utils::trunc)
+delegate!(
+    // intrinsics
+    fn abs(n: f32) -> f32 = intrinsics::fabsf32,
+    fn cos(n: f32) -> f32 = intrinsics::cosf32,
+    fn exp(n: f32) -> f32 = intrinsics::expf32,
+    fn exp2(n: f32) -> f32 = intrinsics::exp2f32,
+    fn floor(x: f32) -> f32 = intrinsics::floorf32,
+    fn ln(n: f32) -> f32 = intrinsics::logf32,
+    fn log10(n: f32) -> f32 = intrinsics::log10f32,
+    fn log2(n: f32) -> f32 = intrinsics::log2f32,
+    fn mul_add(a: f32, b: f32, c: f32) -> f32 = intrinsics::fmaf32,
+    fn pow(n: f32, e: f32) -> f32 = intrinsics::powf32,
+    fn powi(n: f32, e: c_int) -> f32 = intrinsics::powif32,
+    fn sin(n: f32) -> f32 = intrinsics::sinf32,
+    fn sqrt(n: f32) -> f32 = intrinsics::sqrtf32,
+
+    // LLVM 3.3 required to use intrinsics for these four
+    fn ceil(n: c_float) -> c_float = c_float_utils::ceil,
+    fn trunc(n: c_float) -> c_float = c_float_utils::trunc,
+    /*
+    fn ceil(n: f32) -> f32 = intrinsics::ceilf32,
+    fn trunc(n: f32) -> f32 = intrinsics::truncf32,
+    fn rint(n: f32) -> f32 = intrinsics::rintf32,
+    fn nearbyint(n: f32) -> f32 = intrinsics::nearbyintf32,
+    */
+
+    // cmath
+    fn acos(n: c_float) -> c_float = c_float_utils::acos,
+    fn asin(n: c_float) -> c_float = c_float_utils::asin,
+    fn atan(n: c_float) -> c_float = c_float_utils::atan,
+    fn atan2(a: c_float, b: c_float) -> c_float = c_float_utils::atan2,
+    fn cbrt(n: c_float) -> c_float = c_float_utils::cbrt,
+    fn copysign(x: c_float, y: c_float) -> c_float = c_float_utils::copysign,
+    fn cosh(n: c_float) -> c_float = c_float_utils::cosh,
+    fn erf(n: c_float) -> c_float = c_float_utils::erf,
+    fn erfc(n: c_float) -> c_float = c_float_utils::erfc,
+    fn expm1(n: c_float) -> c_float = c_float_utils::expm1,
+    fn abs_sub(a: c_float, b: c_float) -> c_float = c_float_utils::abs_sub,
+    fn fmax(a: c_float, b: c_float) -> c_float = c_float_utils::fmax,
+    fn fmin(a: c_float, b: c_float) -> c_float = c_float_utils::fmin,
+    fn nextafter(x: c_float, y: c_float) -> c_float = c_float_utils::nextafter,
+    fn frexp(n: c_float, value: &mut c_int) -> c_float = c_float_utils::frexp,
+    fn hypot(x: c_float, y: c_float) -> c_float = c_float_utils::hypot,
+    fn ldexp(x: c_float, n: c_int) -> c_float = c_float_utils::ldexp,
+    fn lgamma(n: c_float, sign: &mut c_int) -> c_float = c_float_utils::lgamma,
+    fn log_radix(n: c_float) -> c_float = c_float_utils::log_radix,
+    fn ln1p(n: c_float) -> c_float = c_float_utils::ln1p,
+    fn ilog_radix(n: c_float) -> c_int = c_float_utils::ilog_radix,
+    fn modf(n: c_float, iptr: &mut c_float) -> c_float = c_float_utils::modf,
+    fn round(n: c_float) -> c_float = c_float_utils::round,
+    fn ldexp_radix(n: c_float, i: c_int) -> c_float = c_float_utils::ldexp_radix,
+    fn sinh(n: c_float) -> c_float = c_float_utils::sinh,
+    fn tan(n: c_float) -> c_float = c_float_utils::tan,
+    fn tanh(n: c_float) -> c_float = c_float_utils::tanh,
+    fn tgamma(n: c_float) -> c_float = c_float_utils::tgamma)
+
 
 // These are not defined inside consts:: for consistency with
 // the integer types
@@ -143,9 +154,6 @@ pub fn ge(x: f32, y: f32) -> bool { return x >= y; }
 #[inline(always)]
 pub fn gt(x: f32, y: f32) -> bool { return x > y; }
 
-/// Returns `x` rounded down
-#[inline(always)]
-pub fn floor(x: f32) -> f32 { unsafe { floorf32(x) } }
 
 // FIXME (#1999): replace the predicates below with llvm intrinsics or
 // calls to the libmath macros in the rust runtime for performance.
diff --git a/src/libcore/num/f64.rs b/src/libcore/num/f64.rs
index b4eaa0e7fdc6..7f32893f5bff 100644
--- a/src/libcore/num/f64.rs
+++ b/src/libcore/num/f64.rs
@@ -10,12 +10,9 @@
 
 //! Operations and constants for `f64`
 
-use cmath;
-use libc::{c_double, c_int};
 use num::strconv;
 use num;
 use option::Option;
-use unstable::intrinsics::floorf64;
 use to_str;
 use from_str;
 
@@ -25,87 +22,98 @@ use from_str;
 pub use cmath::c_double_targ_consts::*;
 pub use cmp::{min, max};
 
+// An inner module is required to get the #[inline(always)] attribute on the
+// functions.
+pub use self::delegated::*;
+
 macro_rules! delegate(
     (
-        fn $name:ident(
-            $(
-                $arg:ident : $arg_ty:ty
-            ),*
-        ) -> $rv:ty = $bound_name:path
+        $(
+            fn $name:ident(
+                $(
+                    $arg:ident : $arg_ty:ty
+                ),*
+            ) -> $rv:ty = $bound_name:path
+        ),*
     ) => (
-        pub fn $name($( $arg : $arg_ty ),*) -> $rv {
-            unsafe {
-                $bound_name($( $arg ),*)
-            }
+        mod delegated {
+            use cmath::c_double_utils;
+            use libc::{c_double, c_int};
+            use unstable::intrinsics;
+
+            $(
+                #[inline(always)]
+                pub fn $name($( $arg : $arg_ty ),*) -> $rv {
+                    unsafe {
+                        $bound_name($( $arg ),*)
+                    }
+                }
+            )*
         }
     )
 )
 
-delegate!(fn acos(n: c_double) -> c_double = cmath::c_double_utils::acos)
-delegate!(fn asin(n: c_double) -> c_double = cmath::c_double_utils::asin)
-delegate!(fn atan(n: c_double) -> c_double = cmath::c_double_utils::atan)
-delegate!(fn atan2(a: c_double, b: c_double) -> c_double =
-    cmath::c_double_utils::atan2)
-delegate!(fn cbrt(n: c_double) -> c_double = cmath::c_double_utils::cbrt)
-delegate!(fn ceil(n: c_double) -> c_double = cmath::c_double_utils::ceil)
-delegate!(fn copysign(x: c_double, y: c_double) -> c_double =
-    cmath::c_double_utils::copysign)
-delegate!(fn cos(n: c_double) -> c_double = cmath::c_double_utils::cos)
-delegate!(fn cosh(n: c_double) -> c_double = cmath::c_double_utils::cosh)
-delegate!(fn erf(n: c_double) -> c_double = cmath::c_double_utils::erf)
-delegate!(fn erfc(n: c_double) -> c_double = cmath::c_double_utils::erfc)
-delegate!(fn exp(n: c_double) -> c_double = cmath::c_double_utils::exp)
-delegate!(fn expm1(n: c_double) -> c_double = cmath::c_double_utils::expm1)
-delegate!(fn exp2(n: c_double) -> c_double = cmath::c_double_utils::exp2)
-delegate!(fn abs(n: c_double) -> c_double = cmath::c_double_utils::abs)
-delegate!(fn abs_sub(a: c_double, b: c_double) -> c_double =
-    cmath::c_double_utils::abs_sub)
-delegate!(fn mul_add(a: c_double, b: c_double, c: c_double) -> c_double =
-    cmath::c_double_utils::mul_add)
-delegate!(fn fmax(a: c_double, b: c_double) -> c_double =
-    cmath::c_double_utils::fmax)
-delegate!(fn fmin(a: c_double, b: c_double) -> c_double =
-    cmath::c_double_utils::fmin)
-delegate!(fn nextafter(x: c_double, y: c_double) -> c_double =
-    cmath::c_double_utils::nextafter)
-delegate!(fn frexp(n: c_double, value: &mut c_int) -> c_double =
-    cmath::c_double_utils::frexp)
-delegate!(fn hypot(x: c_double, y: c_double) -> c_double =
-    cmath::c_double_utils::hypot)
-delegate!(fn ldexp(x: c_double, n: c_int) -> c_double =
-    cmath::c_double_utils::ldexp)
-delegate!(fn lgamma(n: c_double, sign: &mut c_int) -> c_double =
-    cmath::c_double_utils::lgamma)
-delegate!(fn ln(n: c_double) -> c_double = cmath::c_double_utils::ln)
-delegate!(fn log_radix(n: c_double) -> c_double =
-    cmath::c_double_utils::log_radix)
-delegate!(fn ln1p(n: c_double) -> c_double = cmath::c_double_utils::ln1p)
-delegate!(fn log10(n: c_double) -> c_double = cmath::c_double_utils::log10)
-delegate!(fn log2(n: c_double) -> c_double = cmath::c_double_utils::log2)
-delegate!(fn ilog_radix(n: c_double) -> c_int =
-    cmath::c_double_utils::ilog_radix)
-delegate!(fn modf(n: c_double, iptr: &mut c_double) -> c_double =
-    cmath::c_double_utils::modf)
-delegate!(fn pow(n: c_double, e: c_double) -> c_double =
-    cmath::c_double_utils::pow)
-delegate!(fn round(n: c_double) -> c_double = cmath::c_double_utils::round)
-delegate!(fn ldexp_radix(n: c_double, i: c_int) -> c_double =
-    cmath::c_double_utils::ldexp_radix)
-delegate!(fn sin(n: c_double) -> c_double = cmath::c_double_utils::sin)
-delegate!(fn sinh(n: c_double) -> c_double = cmath::c_double_utils::sinh)
-delegate!(fn sqrt(n: c_double) -> c_double = cmath::c_double_utils::sqrt)
-delegate!(fn tan(n: c_double) -> c_double = cmath::c_double_utils::tan)
-delegate!(fn tanh(n: c_double) -> c_double = cmath::c_double_utils::tanh)
-delegate!(fn tgamma(n: c_double) -> c_double = cmath::c_double_utils::tgamma)
-delegate!(fn trunc(n: c_double) -> c_double = cmath::c_double_utils::trunc)
-delegate!(fn j0(n: c_double) -> c_double = cmath::c_double_utils::j0)
-delegate!(fn j1(n: c_double) -> c_double = cmath::c_double_utils::j1)
-delegate!(fn jn(i: c_int, n: c_double) -> c_double =
-    cmath::c_double_utils::jn)
-delegate!(fn y0(n: c_double) -> c_double = cmath::c_double_utils::y0)
-delegate!(fn y1(n: c_double) -> c_double = cmath::c_double_utils::y1)
-delegate!(fn yn(i: c_int, n: c_double) -> c_double =
-    cmath::c_double_utils::yn)
+delegate!(
+    // intrinsics
+    fn abs(n: f64) -> f64 = intrinsics::fabsf64,
+    fn cos(n: f64) -> f64 = intrinsics::cosf64,
+    fn exp(n: f64) -> f64 = intrinsics::expf64,
+    fn exp2(n: f64) -> f64 = intrinsics::exp2f64,
+    fn floor(x: f64) -> f64 = intrinsics::floorf64,
+    fn ln(n: f64) -> f64 = intrinsics::logf64,
+    fn log10(n: f64) -> f64 = intrinsics::log10f64,
+    fn log2(n: f64) -> f64 = intrinsics::log2f64,
+    fn mul_add(a: f64, b: f64, c: f64) -> f64 = intrinsics::fmaf64,
+    fn pow(n: f64, e: f64) -> f64 = intrinsics::powf64,
+    fn powi(n: f64, e: c_int) -> f64 = intrinsics::powif64,
+    fn sin(n: f64) -> f64 = intrinsics::sinf64,
+    fn sqrt(n: f64) -> f64 = intrinsics::sqrtf64,
+
+    // LLVM 3.3 required to use intrinsics for these four
+    fn ceil(n: c_double) -> c_double = c_double_utils::ceil,
+    fn trunc(n: c_double) -> c_double = c_double_utils::trunc,
+    /*
+    fn ceil(n: f64) -> f64 = intrinsics::ceilf64,
+    fn trunc(n: f64) -> f64 = intrinsics::truncf64,
+    fn rint(n: c_double) -> c_double = intrinsics::rintf64,
+    fn nearbyint(n: c_double) -> c_double = intrinsics::nearbyintf64,
+    */
+
+    // cmath
+    fn acos(n: c_double) -> c_double = c_double_utils::acos,
+    fn asin(n: c_double) -> c_double = c_double_utils::asin,
+    fn atan(n: c_double) -> c_double = c_double_utils::atan,
+    fn atan2(a: c_double, b: c_double) -> c_double = c_double_utils::atan2,
+    fn cbrt(n: c_double) -> c_double = c_double_utils::cbrt,
+    fn copysign(x: c_double, y: c_double) -> c_double = c_double_utils::copysign,
+    fn cosh(n: c_double) -> c_double = c_double_utils::cosh,
+    fn erf(n: c_double) -> c_double = c_double_utils::erf,
+    fn erfc(n: c_double) -> c_double = c_double_utils::erfc,
+    fn expm1(n: c_double) -> c_double = c_double_utils::expm1,
+    fn abs_sub(a: c_double, b: c_double) -> c_double = c_double_utils::abs_sub,
+    fn fmax(a: c_double, b: c_double) -> c_double = c_double_utils::fmax,
+    fn fmin(a: c_double, b: c_double) -> c_double = c_double_utils::fmin,
+    fn nextafter(x: c_double, y: c_double) -> c_double = c_double_utils::nextafter,
+    fn frexp(n: c_double, value: &mut c_int) -> c_double = c_double_utils::frexp,
+    fn hypot(x: c_double, y: c_double) -> c_double = c_double_utils::hypot,
+    fn ldexp(x: c_double, n: c_int) -> c_double = c_double_utils::ldexp,
+    fn lgamma(n: c_double, sign: &mut c_int) -> c_double = c_double_utils::lgamma,
+    fn log_radix(n: c_double) -> c_double = c_double_utils::log_radix,
+    fn ln1p(n: c_double) -> c_double = c_double_utils::ln1p,
+    fn ilog_radix(n: c_double) -> c_int = c_double_utils::ilog_radix,
+    fn modf(n: c_double, iptr: &mut c_double) -> c_double = c_double_utils::modf,
+    fn round(n: c_double) -> c_double = c_double_utils::round,
+    fn ldexp_radix(n: c_double, i: c_int) -> c_double = c_double_utils::ldexp_radix,
+    fn sinh(n: c_double) -> c_double = c_double_utils::sinh,
+    fn tan(n: c_double) -> c_double = c_double_utils::tan,
+    fn tanh(n: c_double) -> c_double = c_double_utils::tanh,
+    fn tgamma(n: c_double) -> c_double = c_double_utils::tgamma,
+    fn j0(n: c_double) -> c_double = c_double_utils::j0,
+    fn j1(n: c_double) -> c_double = c_double_utils::j1,
+    fn jn(i: c_int, n: c_double) -> c_double = c_double_utils::jn,
+    fn y0(n: c_double) -> c_double = c_double_utils::y0,
+    fn y1(n: c_double) -> c_double = c_double_utils::y1,
+    fn yn(i: c_int, n: c_double) -> c_double = c_double_utils::yn)
 
 // FIXME (#1433): obtain these in a different way
 
@@ -218,9 +226,6 @@ pub fn is_finite(x: f64) -> bool {
     return !(is_NaN(x) || is_infinite(x));
 }
 
-/// Returns `x` rounded down
-#[inline(always)]
-pub fn floor(x: f64) -> f64 { unsafe { floorf64(x) } }
 
 // FIXME (#1999): add is_normal, is_subnormal, and fpclassify
 
diff --git a/src/libcore/num/float.rs b/src/libcore/num/float.rs
index 38111210c73c..c9cda20640d5 100644
--- a/src/libcore/num/float.rs
+++ b/src/libcore/num/float.rs
@@ -36,7 +36,7 @@ pub use f64::{acos, asin, atan2, cbrt, ceil, copysign, cosh, floor};
 pub use f64::{erf, erfc, exp, expm1, exp2, abs_sub};
 pub use f64::{mul_add, fmax, fmin, nextafter, frexp, hypot, ldexp};
 pub use f64::{lgamma, ln, log_radix, ln1p, log10, log2, ilog_radix};
-pub use f64::{modf, pow, round, sinh, tanh, tgamma, trunc};
+pub use f64::{modf, pow, powi, round, sinh, tanh, tgamma, trunc};
 pub use f64::signbit;
 pub use f64::{j0, j1, jn, y0, y1, yn};
 
diff --git a/src/libcore/unstable/intrinsics.rs b/src/libcore/unstable/intrinsics.rs
index ba96c6e5d303..a18ad1738861 100644
--- a/src/libcore/unstable/intrinsics.rs
+++ b/src/libcore/unstable/intrinsics.rs
@@ -70,16 +70,28 @@ pub extern "rust-intrinsic" {
     pub fn powif32(a: f32, x: i32) -> f32;
     pub fn powif64(a: f64, x: i32) -> f64;
 
+    // the following kill the stack canary without
+    // `fixed_stack_segment`. This possibly only affects the f64
+    // variants, but it's hard to be sure since it seems to only
+    // occur with fairly specific arguments.
+    #[fixed_stack_segment]
     pub fn sinf32(x: f32) -> f32;
+    #[fixed_stack_segment]
     pub fn sinf64(x: f64) -> f64;
 
+    #[fixed_stack_segment]
     pub fn cosf32(x: f32) -> f32;
+    #[fixed_stack_segment]
     pub fn cosf64(x: f64) -> f64;
 
+    #[fixed_stack_segment]
     pub fn powf32(a: f32, x: f32) -> f32;
+    #[fixed_stack_segment]
     pub fn powf64(a: f64, x: f64) -> f64;
 
+    #[fixed_stack_segment]
     pub fn expf32(x: f32) -> f32;
+    #[fixed_stack_segment]
     pub fn expf64(x: f64) -> f64;
 
     pub fn exp2f32(x: f32) -> f32;
@@ -128,4 +140,3 @@ pub extern "rust-intrinsic" {
     pub fn bswap32(x: i32) -> i32;
     pub fn bswap64(x: i64) -> i64;
 }
-
diff --git a/src/librustc/middle/trans/foreign.rs b/src/librustc/middle/trans/foreign.rs
index 854ec585d5cc..956ee3bf1443 100644
--- a/src/librustc/middle/trans/foreign.rs
+++ b/src/librustc/middle/trans/foreign.rs
@@ -546,6 +546,7 @@ pub fn trans_intrinsic(ccx: @CrateContext,
                        item: @ast::foreign_item,
                        path: ast_map::path,
                        substs: @param_substs,
+                       attributes: &[ast::attribute],
                        ref_id: Option<ast::node_id>) {
     debug!("trans_intrinsic(item.ident=%s)", *ccx.sess.str_of(item.ident));
 
@@ -561,6 +562,11 @@ pub fn trans_intrinsic(ccx: @CrateContext,
                                Some(copy substs),
                                Some(item.span));
 
+    // Set the fixed stack segment flag if necessary.
+    if attr::attrs_contains_name(attributes, "fixed_stack_segment") {
+        set_fixed_stack_segment(fcx.llfn);
+    }
+
     let mut bcx = top_scope_block(fcx, None), lltop = bcx.llbb;
     match *ccx.sess.str_of(item.ident) {
         ~"atomic_cxchg" => {
diff --git a/src/librustc/middle/trans/monomorphize.rs b/src/librustc/middle/trans/monomorphize.rs
index 9d63ac854a90..52ca8ec49bb7 100644
--- a/src/librustc/middle/trans/monomorphize.rs
+++ b/src/librustc/middle/trans/monomorphize.rs
@@ -212,7 +212,7 @@ pub fn monomorphic_fn(ccx: @CrateContext,
       }
       ast_map::node_foreign_item(i, _, _, _) => {
           let d = mk_lldecl();
-          foreign::trans_intrinsic(ccx, d, i, pt, psubsts.get(),
+          foreign::trans_intrinsic(ccx, d, i, pt, psubsts.get(), i.attrs,
                                 ref_id);
           d
       }
diff --git a/src/test/bench/shootout-nbody.rs b/src/test/bench/shootout-nbody.rs
index e633f307bc22..da06b36af67e 100644
--- a/src/test/bench/shootout-nbody.rs
+++ b/src/test/bench/shootout-nbody.rs
@@ -1,6 +1,5 @@
 use core::from_str::FromStr;
 use core::uint::range;
-use core::unstable::intrinsics::sqrtf64;
 
 static PI: f64 = 3.141592653589793;
 static SOLAR_MASS: f64 = 4.0 * PI * PI;
@@ -88,7 +87,7 @@ fn advance(bodies: &mut [Planet, ..N_BODIES], dt: f64, steps: i32) {
                 d[2] = bodies[i].x[2] - bodies[j].x[2];
 
                 let d2 = d[0]*d[0] + d[1]*d[1] + d[2]*d[2];
-                let mag = dt / (d2 * sqrtf64(d2));
+                let mag = dt / (d2 * f64::sqrt(d2));
 
                 let a_mass = bodies[i].mass, b_mass = bodies[j].mass;
                 bodies[i].v[0] -= d[0] * b_mass * mag;
@@ -121,7 +120,7 @@ fn energy(bodies: &[Planet, ..N_BODIES]) -> f64 {
             for range(0, 3) |k| {
                 d[k] = bodies[i].x[k] - bodies[j].x[k];
             }
-            let dist = sqrtf64(d[0]*d[0] + d[1]*d[1] + d[2]*d[2]);
+            let dist = f64::sqrt(d[0]*d[0] + d[1]*d[1] + d[2]*d[2]);
             e -= bodies[i].mass * bodies[j].mass / dist;
         }
     }
@@ -147,4 +146,3 @@ fn main() {
 
     println(fmt!("%.9f", energy(&bodies) as float));
 }
-
diff --git a/src/test/bench/shootout-spectralnorm.rs b/src/test/bench/shootout-spectralnorm.rs
index 00e255d890b9..6840384ca7c8 100644
--- a/src/test/bench/shootout-spectralnorm.rs
+++ b/src/test/bench/shootout-spectralnorm.rs
@@ -1,6 +1,5 @@
 use core::from_str::FromStr;
 use core::iter::ExtendedMutableIter;
-use core::unstable::intrinsics::sqrtf64;
 
 #[inline]
 fn A(i: i32, j: i32) -> i32 {
@@ -49,6 +48,5 @@ fn main() {
         mult_AtAv(v, u, tmp);
     }
 
-    println(fmt!("%.9f", sqrtf64(dot(u,v) / dot(v,v)) as float));
+    println(fmt!("%.9f", f64::sqrt(dot(u,v) / dot(v,v)) as float));
 }
-