diff options
author | Ludovic Courtès <ludo@gnu.org> | 2019-06-23 11:40:16 +0200 |
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committer | Ludovic Courtès <ludo@gnu.org> | 2019-06-27 11:14:41 +0200 |
commit | fd951cd543d9f4d3ecfa4570e51797f84e79068b (patch) | |
tree | 1786d70a803eba0122ebafd33c3ad77a91283e92 /guix/derivations.scm | |
parent | 5cf4b26d52bcea382d98fb4becce89be9ee37b55 (diff) |
derivations: 'derivation' preserves pointer equality.
* guix/derivations.scm (derivation): Check if FILE is already in
%DERIVATION-CACHE and return it if it is.
Diffstat (limited to 'guix/derivations.scm')
-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 |