diff --git a/array.rs b/array.rs
index 44cd443..48116b6 100644
--- a/array.rs
+++ b/array.rs
@@ -39,6 +39,7 @@ pub type CFArrayRef = *__CFArray;
 
 impl AbstractCFTypeRef for CFArrayRef {
     fn as_type_ref(&self) -> CFTypeRef { *self as CFTypeRef }
+    #[fixed_stack_segment]
     fn type_id() -> CFTypeID { unsafe { CFArrayGetTypeID() } }
 }
 
@@ -77,6 +78,7 @@ impl<ElemRefType:AbstractCFTypeRef> CFArray<ElemRefType> {
         }
     }
 
+    #[fixed_stack_segment]
     pub fn new(elems: &[ElemRefType]) -> CFArray<ElemRefType> {
         let array_ref: CFArrayRef;
         let elems_refs = do elems.map |e: &ElemRefType| { e.as_type_ref() };
@@ -103,6 +105,7 @@ impl<ElemRefType:AbstractCFTypeRef> CFArray<ElemRefType> {
         }
     }
 
+    #[fixed_stack_segment]
     pub fn len(&self) -> uint {
         unsafe {
             return CFArrayGetCount(*self.contents.borrow_ref()) as uint;
@@ -114,6 +117,7 @@ impl<ElemRefType:AbstractCFTypeRef> Index<uint,ElemRefType> for CFArray<ElemRefT
     // Careful; the caller must wrap any returned reference properly.
     // Generally, when array elements are Core Foundation objects (not
     // always true), they need to be wrapped with CFWrapper::wrap_shared.
+    #[fixed_stack_segment]
     fn index(&self, idx: &uint) -> ElemRefType {
         assert!(*idx < self.len());
         unsafe { 
diff --git a/base.rs b/base.rs
index 914bee3..fe451cf 100644
--- a/base.rs
+++ b/base.rs
@@ -51,6 +51,7 @@ impl AbstractCFTypeRef for CFTypeRef {
     fn type_id() -> CFTypeID { fail!(); }
 }
 
+#[fixed_stack_segment]
 pub fn downcast<T:AbstractCFTypeRef>(r: CFTypeRef) -> T {
     unsafe {
         assert!(CFGetTypeID(r) == AbstractCFTypeRef::type_id::<T>());
@@ -68,6 +69,7 @@ pub struct CFWrapper<T, PlaceholderType1, PlaceholderType2> {
 
 #[unsafe_destructor]
 impl<T,E1,E2> Drop for CFWrapper<T,E1,E2> {
+    #[fixed_stack_segment]
     fn drop(&self) {
         unsafe {
             // sadly, cannot use obj.as_type_ref() here, because drop
@@ -104,6 +106,7 @@ impl<'self, T:Clone + AbstractCFTypeRef, E1, E2> CFWrapper<T,E1,E2> {
 
     // Use this when following Core Foundation's "Get" rule. The wrapper does not have ownership.
     // Twe need to increment object's the retain count so it isn't freed out from under our noses.
+    #[fixed_stack_segment]
     pub fn wrap_shared(some_ref: T) -> CFWrapper<T,E1,E2> {
         unsafe { CFRetain(some_ref.as_type_ref()); }
         CFWrapper { obj: some_ref }
@@ -131,18 +134,21 @@ impl<'self, T:Clone + AbstractCFTypeRef, E1, E2> CFWrapper<T,E1,E2> {
         CFWrapper::wrap_shared((*wrapper.borrow_ref()).clone())
     }
 
+    #[fixed_stack_segment]
     pub fn retain_count(&self) -> CFIndex {
         unsafe {
             CFGetRetainCount(*self.borrow_type_ref())
         }
     }
 
+    #[fixed_stack_segment]
     pub fn type_id(&self) -> CFTypeID {
         unsafe {
             CFGetTypeID(*self.borrow_type_ref())
         }
     }
 
+    #[fixed_stack_segment]
     pub fn show(&self) {
         unsafe {
             CFShow(*self.borrow_type_ref());
diff --git a/boolean.rs b/boolean.rs
index dbfc089..bdd8a8e 100644
--- a/boolean.rs
+++ b/boolean.rs
@@ -22,6 +22,7 @@ pub type CFBooleanRef = *__CFBoolean;
 impl AbstractCFTypeRef for CFBooleanRef {
     fn as_type_ref(&self) -> CFTypeRef { *self as CFTypeRef }
 
+    #[fixed_stack_segment]
     fn type_id() -> CFTypeID {
         unsafe { CFBooleanGetTypeID() }
     }
diff --git a/data.rs b/data.rs
index 3c906aa..7ae3a07 100644
--- a/data.rs
+++ b/data.rs
@@ -26,6 +26,7 @@ pub type CFDataRef = *__CFData;
 impl AbstractCFTypeRef for CFDataRef {
     fn as_type_ref(&self) -> CFTypeRef { *self as CFTypeRef }
 
+    #[fixed_stack_segment]
     fn type_id() -> CFTypeID {
         unsafe {
             CFDataGetTypeID()
@@ -46,6 +47,7 @@ impl CFData {
         }
     }
 
+    #[fixed_stack_segment]
     pub fn new_from_buf(buf: &[u8]) -> CFData {
         let result;
         unsafe {
@@ -60,12 +62,14 @@ impl CFData {
     }
 
     // tread with caution; read-only
+    #[fixed_stack_segment]
     pub fn bytes(&self) -> *u8 {
         unsafe {
             CFDataGetBytePtr(self.contents.obj)
         }
     }
 
+    #[fixed_stack_segment]
     pub fn len(&self) -> uint {
         unsafe {
             CFDataGetLength(self.contents.obj) as uint
diff --git a/dictionary.rs b/dictionary.rs
index 5a54ef8..c1d4746 100644
--- a/dictionary.rs
+++ b/dictionary.rs
@@ -54,6 +54,7 @@ pub type CFDictionaryRef = *__CFDictionary;
 impl AbstractCFTypeRef for CFDictionaryRef {
     fn as_type_ref(&self) -> CFTypeRef { *self as CFTypeRef }
 
+    #[fixed_stack_segment]
     fn type_id() -> CFTypeID {
         unsafe {
             CFDictionaryGetTypeID()
@@ -77,6 +78,7 @@ impl<KeyRefType: Clone + AbstractCFTypeRef, ValueRefType: Clone + AbstractCFType
         }
     }
 
+    #[fixed_stack_segment]
     pub fn new(pairs: &[(KeyRefType,ValueRefType)]) -> CFDictionary<KeyRefType, ValueRefType> {
         let mut keys : ~[CFTypeRef] = ~[];
         let mut values : ~[CFTypeRef] = ~[];
@@ -109,6 +111,7 @@ impl<KeyRefType: Clone + AbstractCFTypeRef, ValueRefType: Clone + AbstractCFType
         }
     }
 
+    #[fixed_stack_segment]
     pub fn len(&self) -> uint {
         unsafe {
             CFDictionaryGetCount(self.contents.obj) as uint
@@ -119,6 +122,7 @@ impl<KeyRefType: Clone + AbstractCFTypeRef, ValueRefType: Clone + AbstractCFType
         self.len() == 0
     }
 
+    #[fixed_stack_segment]
     pub fn contains_key(&self, key: &KeyRefType) -> bool {
         unsafe {
             CFDictionaryContainsKey(self.contents.obj, 
@@ -127,6 +131,7 @@ impl<KeyRefType: Clone + AbstractCFTypeRef, ValueRefType: Clone + AbstractCFType
         }
     }
 
+    #[fixed_stack_segment]
     pub fn find(&self, key: &KeyRefType) -> Option<ValueRefType> {
         unsafe {
             let value : *c_void = ptr::null();
diff --git a/number.rs b/number.rs
index 50c359c..258f11c 100644
--- a/number.rs
+++ b/number.rs
@@ -43,6 +43,7 @@ pub type CFNumberRef = *__CFNumber;
 impl AbstractCFTypeRef for CFNumberRef {
     fn as_type_ref(&self) -> CFTypeRef { *self as CFTypeRef }
 
+    #[fixed_stack_segment]
     fn type_id() -> CFTypeID {
         unsafe {
             CFNumberGetTypeID()
@@ -67,6 +68,7 @@ impl CFNumber {
         }
     }
 
+    #[fixed_stack_segment]
     pub fn new<T:Clone + ConvertibleToCFNumber>(n: T) -> CFNumber {
         unsafe {
             let objref = CFNumberCreate(kCFAllocatorDefault,
@@ -78,6 +80,7 @@ impl CFNumber {
         }
     }
 
+    #[fixed_stack_segment]
     pub fn to_i8(&self) -> i8 {
         let ty = kCFNumberSInt8Type;
         assert!(self.has_number_type(ty));
@@ -90,6 +93,7 @@ impl CFNumber {
         }
     }
 
+    #[fixed_stack_segment]
     pub fn to_i16(&self) -> i16 {
         let ty = kCFNumberSInt16Type;
         assert!(self.has_number_type(ty));
@@ -102,6 +106,7 @@ impl CFNumber {
         }
     }
 
+    #[fixed_stack_segment]
     pub fn to_i32(&self) -> i32 {
         let ty = kCFNumberSInt32Type;
         assert!(self.has_number_type(ty));
@@ -114,6 +119,7 @@ impl CFNumber {
         }
     }
 
+    #[fixed_stack_segment]
     pub fn to_float(&self) -> float {
         unsafe {
             assert!(self.has_float_type());
@@ -141,12 +147,14 @@ impl CFNumber {
         }
     }
 
+    #[fixed_stack_segment]
     fn has_float_type(&self) -> bool {
         unsafe {
             CFNumberIsFloatType(self.contents.obj) as bool
         }
     }
 
+    #[fixed_stack_segment]
     fn has_number_type(&self, ty: CFNumberType) -> bool {
         unsafe {
             CFNumberGetType(self.contents.obj) == ty
diff --git a/set.rs b/set.rs
index 2e00f80..aac9696 100644
--- a/set.rs
+++ b/set.rs
@@ -42,6 +42,7 @@ pub type CFSetRef = *__CFSet;
 impl AbstractCFTypeRef for CFSetRef {
     fn as_type_ref(&self) -> CFTypeRef { *self as CFTypeRef }
 
+    #[fixed_stack_segment]
     fn type_id() -> CFTypeID {
         unsafe {
             CFSetGetTypeID()
@@ -56,6 +57,7 @@ pub struct CFSet<ElemRefType> {
 }
 
 impl<ElemRefType : AbstractCFTypeRef> CFSet<ElemRefType> {
+    #[fixed_stack_segment]
     pub fn new(elems: &[ElemRefType]) -> CFSet<ElemRefType> {
         let result: CFSetRef;
         let elems_refs = do elems.map |e: &ElemRefType| {
diff --git a/string.rs b/string.rs
index 276f722..4702f45 100644
--- a/string.rs
+++ b/string.rs
@@ -202,6 +202,7 @@ pub type CFStringRef = *__CFString;
 impl AbstractCFTypeRef for CFStringRef {
     fn as_type_ref(&self) -> CFTypeRef { *self as CFTypeRef }
 
+    #[fixed_stack_segment]
     fn type_id() -> CFTypeID {
         unsafe {
             CFStringGetTypeID()
@@ -233,6 +234,7 @@ impl CFString {
 
     // like CFString::new, but references a string that can be used as
     // a backing store by virtue of being statically allocated.
+    #[fixed_stack_segment]
     pub fn new_static(string: &'static str) -> CFString {
         let string_ref = do string.as_imm_buf |bytes, len| {
             unsafe {
@@ -250,6 +252,7 @@ impl CFString {
         }
     }
 
+    #[fixed_stack_segment]
     pub fn new(string: &str) -> CFString {
         let string_ref = do string.as_imm_buf |bytes, len| {
             unsafe {
@@ -267,6 +270,7 @@ impl CFString {
         }
     }
 
+    #[fixed_stack_segment]
     pub fn char_len(&self) -> uint {
         unsafe {
             CFStringGetLength(self.contents.obj) as uint
@@ -275,6 +279,7 @@ impl CFString {
 }
 
 impl ToStr for CFString {
+    #[fixed_stack_segment]
     fn to_str(&self) -> ~str {
         unsafe {
             let char_len = self.char_len();
diff --git a/url.rs b/url.rs
index f03f943..b22a8ee 100644
--- a/url.rs
+++ b/url.rs
@@ -19,6 +19,7 @@ pub type CFURLRef = *__CFURL;
 impl AbstractCFTypeRef for CFURLRef {
     fn as_type_ref(&self) -> CFTypeRef { *self as CFTypeRef }
 
+    #[fixed_stack_segment]
     fn type_id() -> CFTypeID {
         unsafe {
             CFURLGetTypeID()
@@ -29,6 +30,7 @@ impl AbstractCFTypeRef for CFURLRef {
 pub type CFURL = CFWrapper<CFURLRef, (), ()>;
 
 impl ToStr for CFURL {
+    #[fixed_stack_segment]
     fn to_str(&self) -> ~str {
         unsafe {
             let cfstr: CFString = CFString {