diff --git a/library/core/src/num/f16.rs b/library/core/src/num/f16.rs
index 3c58b0af9c2..e74300d6c2f 100644
--- a/library/core/src/num/f16.rs
+++ b/library/core/src/num/f16.rs
@@ -507,8 +507,8 @@ impl f16 {
     ///
     /// ```
     /// #![feature(f16)]
-    /// # // FIXME(f16_f128): remove when `extendhfsf2` and `truncsfhf2` are available
-    /// # #[cfg(target_os = "linux")] {
+    /// # // FIXME(f16_f128): extendhfsf2, truncsfhf2, __gnu_h2f_ieee, __gnu_f2h_ieee missing for many platforms
+    /// # #[cfg(all(target_arch = "x86_64", target_os = "linux"))] {
     ///
     /// let x = 2.0_f16;
     /// let abs_difference = (x.recip() - (1.0 / x)).abs();
@@ -528,8 +528,8 @@ impl f16 {
     ///
     /// ```
     /// #![feature(f16)]
-    /// # // FIXME(f16_f128): remove when `extendhfsf2` and `truncsfhf2` are available
-    /// # #[cfg(target_os = "linux")] {
+    /// # // FIXME(f16_f128): extendhfsf2, truncsfhf2, __gnu_h2f_ieee, __gnu_f2h_ieee missing for many platforms
+    /// # #[cfg(all(target_arch = "x86_64", target_os = "linux"))] {
     ///
     /// let angle = std::f16::consts::PI;
     ///
@@ -551,8 +551,8 @@ impl f16 {
     ///
     /// ```
     /// #![feature(f16)]
-    /// # // FIXME(f16_f128): remove when `extendhfsf2` and `truncsfhf2` are available
-    /// # #[cfg(target_os = "linux")] {
+    /// # // FIXME(f16_f128): extendhfsf2, truncsfhf2, __gnu_h2f_ieee, __gnu_f2h_ieee missing for many platforms
+    /// # #[cfg(all(target_arch = "x86_64", target_os = "linux"))] {
     ///
     /// let angle = 180.0f16;
     ///
@@ -870,6 +870,8 @@ impl f16 {
     ///
     /// ```
     /// #![feature(f16)]
+    /// # // FIXME(f16_f128): extendhfsf2, truncsfhf2, __gnu_h2f_ieee, __gnu_f2h_ieee missing for many platforms
+    /// # #[cfg(all(target_arch = "x86_64", target_os = "linux"))] {
     ///
     /// struct GoodBoy {
     ///     name: &'static str,
@@ -897,6 +899,7 @@ impl f16 {
     ///         .zip([-5.0, 0.1, 10.0, 99.0, f16::INFINITY, f16::NAN].iter())
     ///         .for_each(|(a, b)| assert_eq!(a.to_bits(), b.to_bits()))
     /// }
+    /// # }
     /// ```
     #[inline]
     #[must_use]
diff --git a/library/std/build.rs b/library/std/build.rs
index 55388648a14..c542ba81eed 100644
--- a/library/std/build.rs
+++ b/library/std/build.rs
@@ -99,7 +99,9 @@ fn main() {
         // the compiler-builtins update. <https://github.com/rust-lang/rust/issues/123885>
         ("x86" | "x86_64", _) => false,
         // Missing `__gnu_h2f_ieee` and `__gnu_f2h_ieee`
-        ("powerpc" | "powerpc64" | "powerpc64le", _) => false,
+        ("powerpc" | "powerpc64", _) => false,
+        // Missing `__gnu_h2f_ieee` and `__gnu_f2h_ieee`
+        ("mips" | "mips32r6" | "mips64" | "mips64r6", _) => false,
         // Missing `__extendhfsf` and `__truncsfhf`
         ("riscv32" | "riscv64", _) => false,
         // Most OSs are missing `__extendhfsf` and `__truncsfhf`