Rollup of 5 pull requests

.azure-pipelines/steps/run.yml

@@ -50,6 +50,7 @@ steps:
 # on since libstd tests require it
 - bash: |
     set -e
+    sudo mkdir -p /etc/docker
     echo '{"ipv6":true,"fixed-cidr-v6":"fd9a:8454:6789:13f7::/64"}' | sudo tee /etc/docker/daemon.json
     sudo service docker restart
   displayName: Enable IPv6
@@ -101,6 +102,10 @@ steps:
 
 - bash: |
     set -e
+    # Remove any preexisting rustup installation since it can interfere
+    # with the cargotest step and its auto-detection of things like Clippy in
+    # the environment
+    rustup self uninstall -y || true
     if [ "$IMAGE" = "" ]; then
       src/ci/run.sh
     else

src/librustc_mir/transform/qualify_consts.rs

@@ -1304,7 +1304,9 @@ impl<'a, 'tcx> Visitor<'tcx> for Checker<'a, 'tcx> {
                 }
             }
 
-            if self.mode == Mode::Fn {
+            // No need to do anything in constants and statics, as everything is "constant" anyway
+            // so promotion would be useless.
+            if self.mode != Mode::Static && self.mode != Mode::Const {
                 let constant_args = callee_def_id.and_then(|id| {
                     args_required_const(self.tcx, id)
                 }).unwrap_or_default();

src/librustc_target/spec/netbsd_base.rs

@@ -9,9 +9,6 @@ pub fn opts() -> TargetOptions {
         // libraries which follow this flag.  Thus, use it before
         // specifying libraries to link to.
         "-Wl,--as-needed".to_string(),
-
-        // Always enable NX protection when it is available
-        "-Wl,-z,noexecstack".to_string(),
     ]);
 
     TargetOptions {

src/libstd/lib.rs

@@ -223,7 +223,8 @@
 #![cfg_attr(all(target_vendor = "fortanix", target_env = "sgx"),
             feature(global_asm, slice_index_methods,
                     decl_macro, coerce_unsized, sgx_platform, ptr_wrapping_offset_from))]
-#![cfg_attr(all(test, target_vendor = "fortanix", target_env = "sgx"), feature(fixed_size_array))]
+#![cfg_attr(all(test, target_vendor = "fortanix", target_env = "sgx"),
+            feature(fixed_size_array, maybe_uninit_extra))]
 
 // std is implemented with unstable features, many of which are internal
 // compiler details that will never be stable

src/libstd/process.rs

@@ -1153,10 +1153,13 @@ impl From<fs::File> for Stdio {
 ///
 /// This `struct` is used to represent the exit status of a child process.
 /// Child processes are created via the [`Command`] struct and their exit
-/// status is exposed through the [`status`] method.
+/// status is exposed through the [`status`] method, or the [`wait`] method
+/// of a [`Child`] process.
 ///
 /// [`Command`]: struct.Command.html
+/// [`Child`]: struct.Child.html
 /// [`status`]: struct.Command.html#method.status
+/// [`wait`]: struct.Child.html#method.wait
 #[derive(PartialEq, Eq, Clone, Copy, Debug)]
 #[stable(feature = "process", since = "1.0.0")]
 pub struct ExitStatus(imp::ExitStatus);

src/test/ui/consts/const_arg_promotable2.rs

@@ -0,0 +1,18 @@
+// This test is a regression test for a bug where we only checked function calls in no-const
+// functions for `rustc_args_required_const` arguments. This meant that even though `bar` needs its
+// argument to be const, inside a const fn (callable at runtime), the value for it may come from a
+// non-constant (namely an argument to the const fn).
+
+#![feature(rustc_attrs)]
+const fn foo(a: i32) {
+    bar(a); //~ ERROR argument 1 is required to be a constant
+}
+
+#[rustc_args_required_const(0)]
+const fn bar(_: i32) {}
+
+fn main() {
+    // this function call will pass a runtime-value (number of program arguments) to `foo`, which
+    // will in turn forward it to `bar`, which expects a compile-time argument
+    foo(std::env::args().count() as i32);
+}

src/test/ui/consts/const_arg_promotable2.stderr

@@ -0,0 +1,8 @@
+error: argument 1 is required to be a constant
+  --> $DIR/const_arg_promotable2.rs:8:5
+   |
+LL |     bar(a);
+   |     ^^^^^^
+
+error: aborting due to previous error
+