73/84: gnu: make-rust-sysroot: Memoize make-rust-sysroot results.

[guix-commits]

efraim pushed a commit to branch rust-team
in repository guix.

commit 99d5b77769e7beeb91d21190b76605a573a69d10
Author: Christopher Baines <mail@cbaines.net>
AuthorDate: Fri Jan 5 16:40:49 2024 +0000

    gnu: make-rust-sysroot: Memoize make-rust-sysroot results.
    
    To ensure that it just returns a single package record for some given
    arguments, as this helps to avoid poor performance of the store connection
    object cache.
    
    * gnu/packages/rust.scm (make-rust-sysroot): Move code to
    make-rust-sysroot/implementation.
    (make-rust-sysroot/implementation): New variable.
    
    Change-Id: Ibb30c7398328c87c032bb8828635a34ada935167
---
 gnu/packages/rust.scm | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/gnu/packages/rust.scm b/gnu/packages/rust.scm
index 452d8cbaa3..13eff46f37 100644
--- a/gnu/packages/rust.scm
+++ b/gnu/packages/rust.scm
@@ -59,6 +59,7 @@
   #:use-module (guix build-system gnu)
   #:use-module (guix build-system trivial)
   #:use-module (guix download)
+  #:use-module (guix memoization)
   #:use-module (guix git-download)
   #:use-module ((guix licenses) #:prefix license:)
   #:use-module (guix packages)
@@ -1077,7 +1078,10 @@ exec -a \"$0\" \"~a\" \"$@\""
                             (package-native-inputs base-rust))))))
 
 (define*-public (make-rust-sysroot target)
-  (let ((base-rust rust))
+  (make-rust-sysroot/implementation target rust))
+
+(define make-rust-sysroot/implementation
+  (mlambda (target base-rust)
     (package
       (inherit base-rust)
       (name (string-append "rust-sysroot-for-" target))