diff --git a/src/float/conv.rs b/src/float/conv.rs
index 4f52ac71..42a526bd 100644
--- a/src/float/conv.rs
+++ b/src/float/conv.rs
@@ -403,7 +403,6 @@ intrinsics! {
         float_to_unsigned_int(f)
     }
 
-    #[win64_128bit_abi_hack]
     pub extern "C" fn __fixunssfti(f: f32) -> u128 {
         float_to_unsigned_int(f)
     }
@@ -418,7 +417,6 @@ intrinsics! {
         float_to_unsigned_int(f)
     }
 
-    #[win64_128bit_abi_hack]
     pub extern "C" fn __fixunsdfti(f: f64) -> u128 {
         float_to_unsigned_int(f)
     }
@@ -454,7 +452,6 @@ intrinsics! {
         float_to_signed_int(f)
     }
 
-    #[win64_128bit_abi_hack]
     pub extern "C" fn __fixsfti(f: f32) -> i128 {
         float_to_signed_int(f)
     }
@@ -469,7 +466,6 @@ intrinsics! {
         float_to_signed_int(f)
     }
 
-    #[win64_128bit_abi_hack]
     pub extern "C" fn __fixdfti(f: f64) -> i128 {
         float_to_signed_int(f)
     }
diff --git a/src/int/sdiv.rs b/src/int/sdiv.rs
index 9d316c76..9630c7d7 100644
--- a/src/int/sdiv.rs
+++ b/src/int/sdiv.rs
@@ -165,5 +165,5 @@ sdivmod!(
     i128,
     maybe_use_optimized_c_shim
 );
-sdiv!(__udivti3, __divti3, u128, i128, win64_128bit_abi_hack);
-smod!(__umodti3, __modti3, u128, i128, win64_128bit_abi_hack);
+sdiv!(__udivti3, __divti3, u128, i128,);
+smod!(__umodti3, __modti3, u128, i128,);
diff --git a/src/int/udiv.rs b/src/int/udiv.rs
index c891eede..1fa76121 100644
--- a/src/int/udiv.rs
+++ b/src/int/udiv.rs
@@ -58,7 +58,6 @@ intrinsics! {
     // the existence of `u128_div_rem` to get 32-bit SPARC to compile, see `u128_divide_sparc` docs.
 
     #[avr_skip]
-    #[win64_128bit_abi_hack]
     /// Returns `n / d`
     pub extern "C" fn __udivti3(n: u128, d: u128) -> u128 {
         #[cfg(not(any(target_arch = "sparc", target_arch = "sparc64")))] {
@@ -70,7 +69,6 @@ intrinsics! {
     }
 
     #[avr_skip]
-    #[win64_128bit_abi_hack]
     /// Returns `n % d`
     pub extern "C" fn __umodti3(n: u128, d: u128) -> u128 {
         #[cfg(not(any(target_arch = "sparc", target_arch = "sparc64")))] {
@@ -84,7 +82,6 @@ intrinsics! {
     }
 
     #[avr_skip]
-    #[win64_128bit_abi_hack]
     /// Returns `n / d` and sets `*rem = n % d`
     pub extern "C" fn __udivmodti4(n: u128, d: u128, rem: Option<&mut u128>) -> u128 {
         #[cfg(not(any(target_arch = "sparc", target_arch = "sparc64")))] {
diff --git a/src/macros.rs b/src/macros.rs
index f51e49e9..88b54e82 100644
--- a/src/macros.rs
+++ b/src/macros.rs
@@ -60,9 +60,6 @@ macro_rules! public_test_dep {
 ///   the specified ABI everywhere else.
 /// * `unadjusted_on_win64` - like `aapcs_on_arm` this switches to the
 ///   `"unadjusted"` abi on Win64 and the specified abi elsewhere.
-/// * `win64_128bit_abi_hack` - this attribute is used for 128-bit integer
-///   intrinsics where the ABI is slightly tweaked on Windows platforms, but
-///   it's a normal ABI elsewhere for returning a 128 bit integer.
 /// * `arm_aeabi_alias` - handles the "aliasing" of various intrinsics on ARM
 ///   their otherwise typical names to other prefixed ones.
 /// * `ppc_alias` - changes the name of the symbol on PowerPC platforms without
@@ -231,51 +228,6 @@ macro_rules! intrinsics {
         intrinsics!($($rest)*);
     );
 
-    // Some intrinsics on win64 which return a 128-bit integer have an.. unusual
-    // calling convention. That's managed here with this "abi hack" which alters
-    // the generated symbol's ABI.
-    //
-    // This will still define a function in this crate with the given name and
-    // signature, but the actual symbol for the intrinsic may have a slightly
-    // different ABI on win64.
-    (
-        #[win64_128bit_abi_hack]
-        $(#[$($attr:tt)*])*
-        pub extern $abi:tt fn $name:ident( $($argname:ident:  $ty:ty),* ) $(-> $ret:ty)? {
-            $($body:tt)*
-        }
-
-        $($rest:tt)*
-    ) => (
-        #[cfg(all(any(windows, target_os = "uefi"), target_arch = "x86_64"))]
-        $(#[$($attr)*])*
-        pub extern $abi fn $name( $($argname: $ty),* ) $(-> $ret)? {
-            $($body)*
-        }
-
-        #[cfg(all(any(windows, target_os = "uefi"), target_arch = "x86_64", not(feature = "mangled-names")))]
-        mod $name {
-            #[no_mangle]
-            #[cfg_attr(not(all(windows, target_env = "gnu")), linkage = "weak")]
-            extern $abi fn $name( $($argname: $ty),* )
-                -> $crate::macros::win64_128bit_abi_hack::U64x2
-            {
-                let e: $($ret)? = super::$name($($argname),*);
-                $crate::macros::win64_128bit_abi_hack::U64x2::from(e)
-            }
-        }
-
-        #[cfg(not(all(any(windows, target_os = "uefi"), target_arch = "x86_64")))]
-        intrinsics! {
-            $(#[$($attr)*])*
-            pub extern $abi fn $name( $($argname: $ty),* ) $(-> $ret)? {
-                $($body)*
-            }
-        }
-
-        intrinsics!($($rest)*);
-    );
-
     // `arm_aeabi_alias` would conflict with `f16_apple_{arg,ret}_abi` not handled here. Avoid macro ambiguity by combining in a
     // single `#[]`.
     (
@@ -576,26 +528,3 @@ macro_rules! intrinsics {
         intrinsics!($($rest)*);
     );
 }
-
-// Hack for LLVM expectations for ABI on windows. This is used by the
-// `#[win64_128bit_abi_hack]` attribute recognized above
-#[cfg(all(any(windows, target_os = "uefi"), target_pointer_width = "64"))]
-pub mod win64_128bit_abi_hack {
-    #[repr(simd)]
-    pub struct U64x2([u64; 2]);
-
-    impl From<i128> for U64x2 {
-        fn from(i: i128) -> U64x2 {
-            use crate::int::DInt;
-            let j = i as u128;
-            U64x2([j.lo(), j.hi()])
-        }
-    }
-
-    impl From<u128> for U64x2 {
-        fn from(i: u128) -> U64x2 {
-            use crate::int::DInt;
-            U64x2([i.lo(), i.hi()])
-        }
-    }
-}