--- a/compiler/rustc_lint_defs/src/builtin.rs
+++ b/compiler/rustc_lint_defs/src/builtin.rs
@@ -2749,11 +2749,13 @@
     ///
     /// use std::arch::asm;
     ///
+    /// #[cfg(not(any(target_arch = "powerpc64", target_arch = "s390x")))]
     /// #[naked]
     /// pub fn default_abi() -> u32 {
     ///     unsafe { asm!("", options(noreturn)); }
     /// }
     ///
+    /// #[cfg(not(any(target_arch = "powerpc64", target_arch = "s390x")))]
     /// #[naked]
     /// pub extern "Rust" fn rust_abi() -> u32 {
     ///     unsafe { asm!("", options(noreturn)); }
--- a/src/test/run-make-fulldeps/intrinsic-unreachable/Makefile
+++ b/src/test/run-make-fulldeps/intrinsic-unreachable/Makefile
@@ -1,6 +1,7 @@
 -include ../tools.mk
 
 # ignore-windows-msvc
+# needs-asm-support
 #
 # Because of Windows exception handling, the code is not necessarily any shorter.
 # https://github.com/llvm-mirror/llvm/commit/64b2297786f7fd6f5fa24cdd4db0298fbf211466
--- a/compiler/rustc_lint/src/builtin.rs
+++ b/compiler/rustc_lint/src/builtin.rs
@@ -3136,6 +3136,10 @@
     /// ### Example
     ///
     /// ```rust,compile_fail
+    /// #![cfg_attr(
+    ///  not(any(target_arch = "powerpc64", target_arch = "s390x")),
+    ///  feature(asm_experimental_arch)
+    /// )]
     /// use std::arch::asm;
     ///
     /// fn main() {