https://github.com/rust-lang/rust/pull/114440
From: Ariadne Conill <ariadne@dereferenced.org>
Date: Thu, 3 Aug 2023 15:05:40 -0700
Subject: [PATCH] bootstrap: config: fix version comparison bug

Rust requires a previous version of Rust to build, such as the current version, or the
previous version.  However, the version comparison logic did not take patch releases
into consideration when doing the version comparison for the current branch, e.g.
Rust 1.71.1 could not be built by Rust 1.71.0 because it is neither an exact version
match, or the previous version.

Adjust the version comparison logic to tolerate mismatches in the patch version.

Signed-off-by: Ariadne Conill <ariadne@dereferenced.org>
--- a/src/bootstrap/config.rs
+++ b/src/bootstrap/config.rs
@@ -2004,7 +2004,8 @@ impl Config {
                 .unwrap();
         if !(source_version == rustc_version
             || (source_version.major == rustc_version.major
-                && source_version.minor == rustc_version.minor + 1))
+                && (source_version.minor == rustc_version.minor
+                    || source_version.minor == rustc_version.minor + 1)))
         {
             let prev_version = format!("{}.{}.x", source_version.major, source_version.minor - 1);
             eprintln!(