diff options
| -rw-r--r-- | guix/derivations.scm | 8 |
1 files changed, 6 insertions, 2 deletions
diff --git a/guix/derivations.scm b/guix/derivations.scm index 5c568f223b..403e86749b 100644 --- a/guix/derivations.scm +++ b/guix/derivations.scm @@ -873,8 +873,12 @@ derivation. It is kept as-is, uninterpreted, in the derivation." (append (map derivation-input-path inputs) sources))) (drv* (set-field drv (derivation-file-name) file))) - (hash-set! %derivation-cache file drv*) - drv*))) + ;; Preserve pointer equality. This improves the performance of + ;; 'eq?'-memoization on derivations. + (or (hash-ref %derivation-cache file) + (begin + (hash-set! %derivation-cache file drv*) + drv*))))) (define (invalidate-derivation-caches!) "Invalidate internal derivation caches. This is mostly useful for |