Disable the libc::personality doc test on QEMU

It's failing there with EPERM.  It's probably seccomp's fault

Author: asomers

.github/actions/test/action.yml

@@ -19,13 +19,18 @@ inputs:
     required: false
     default: -D warnings -A unknown-lints
 
+  RUSTDOCFLAGS:
+    required: false
+    default: -D warnings
+
 runs:
   using: "composite"
   steps:
     - name: set up Rust env
       shell: bash
       run: |
         echo "RUSTFLAGS=${{ inputs.RUSTFLAGS }}" >> $GITHUB_ENV
+        echo "RUSTDOCFLAGS=${{ inputs.RUSTDOCFLAGS }}" >> $GITHUB_ENV
 
     - name: test
       shell: bash

.github/workflows/ci.yml

@@ -127,6 +127,7 @@ jobs:
           SUDO: ""
           TOOL: cross
           RUSTFLAGS: --cfg qemu -D warnings
+          RUSTDOCFLAGS: --cfg qemu
 
       - name: before_cache_script
         run: rm -rf $CARGO_HOME/registry/index

src/sys/personality.rs

@@ -78,10 +78,10 @@ pub fn get() -> Result<Persona> {
 ///
 /// Example:
 ///
-// Disable test on aarch64 until we know why it fails.
+// Disable test on aarch64 and with QEMU.  seccomp interference is suspected.
 // https://github.com/nix-rust/nix/issues/2060
-#[cfg_attr(target_arch = "aarch64", doc = " ```no_run")]
-#[cfg_attr(not(target_arch = "aarch64"), doc = " ```")]
+#[cfg_attr(any(qemu, target_arch = "aarch64"), doc = " ```no_run")]
+#[cfg_attr(not(any(qemu, target_arch = "aarch64")), doc = " ```")]
 /// # use nix::sys::personality::{self, Persona};
 /// let mut pers = personality::get().unwrap();
 /// assert!(!pers.contains(Persona::ADDR_NO_RANDOMIZE));