From 105094bc826766620b8a75bd5fb208774d1156b7 Mon Sep 17 00:00:00 2001
From: Jimmy Zuber <4781189+jzuber4@users.noreply.github.com>
Date: Thu, 13 Aug 2026 12:35:03 +0000
Subject: [PATCH] fix(build): raise minimum `cfg_aliases` to 0.2.2

nix's build script invokes the `cfg_aliases!` macro. Under
`cargo -Zdirect-minimal-versions`, cargo pins the declared floor
(0.2.1), whose macro expansion ends in a trailing semicolon in
expression position. Current Rust treats that as a hard error, so
the build script fails to compile and the `minver` CI job breaks.

cfg_aliases 0.2.2 restructured the macro to drop the trailing
semicolon. Raising the floor to 0.2.2 makes the minimum-versions
build compile. cfg_aliases is a build-dependency only (not part of
nix's public API), edition 2018, with no dependencies and no MSRV
bump, so nix's consumers and MSRV are unaffected.
---
 Cargo.toml              | 2 +-
 changelog/2811.fixed.md | 2 ++
 2 files changed, 3 insertions(+), 1 deletion(-)
 create mode 100644 changelog/2811.fixed.md

diff --git a/Cargo.toml b/Cargo.toml
index c4c109a4b6..55de4b4e25 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -90,7 +90,7 @@ caps = "0.5.3"
 sysctl = "0.4"
 
 [build-dependencies]
-cfg_aliases = "0.2.1"
+cfg_aliases = "0.2.2"
 
 [[test]]
 name = "test"
diff --git a/changelog/2811.fixed.md b/changelog/2811.fixed.md
new file mode 100644
index 0000000000..a5d07816c2
--- /dev/null
+++ b/changelog/2811.fixed.md
@@ -0,0 +1,2 @@
+Raised the minimum `cfg_aliases` build-dependency to 0.2.2, which is required to
+build nix's build script under `cargo -Zdirect-minimal-versions` on current Rust.