gnu: commencement: Memoize 'linux-libre-headers-boot0'.

Fixes <https://bugs.gnu.org/30155>.

The effect can be seen in the package graph produced by:

  guix graph -e '(@@ (gnu packages commencement) static-bash-for-glibc)'

This reduces the number of "duplicate" nodes in this graph, i.e.,
distinct package objects that correspond to the same derivation (objects
that are not 'eq?' but semantically equal.)

* gnu/packages/commencement.scm (linux-libre-headers-boot0): Make an
'mlambda' instead of a 'lambda'.
(hurd-core-headers-boot0): Ditto.
This commit is contained in:
Ludovic Courtès 2018-01-18 16:14:06 +01:00
parent e80514bc03
commit 8102cf0b37
No known key found for this signature in database
GPG Key ID: 090B11993D9AEBB5
2 changed files with 31 additions and 23 deletions

@ -47,6 +47,7 @@
#:use-module (guix download)
#:use-module (guix build-system gnu)
#:use-module (guix build-system trivial)
#:use-module (guix memoization)
#:use-module (guix utils)
#:use-module (srfi srfi-1)
#:use-module (srfi srfi-26)
@ -371,18 +372,21 @@
(current-source-location)
#:guile %bootstrap-guile))))
(define (linux-libre-headers-boot0)
"Return Linux-Libre header files for the bootstrap environment."
;; Note: this is wrapped in a thunk to nicely handle circular dependencies
;; between (gnu packages linux) and this module.
(package-with-bootstrap-guile
(package (inherit linux-libre-headers)
(arguments `(#:guile ,%bootstrap-guile
#:implicit-inputs? #f
,@(package-arguments linux-libre-headers)))
(native-inputs
`(("perl" ,perl-boot0)
,@%boot0-inputs)))))
(define linux-libre-headers-boot0
(mlambda ()
"Return Linux-Libre header files for the bootstrap environment."
;; Note: this is wrapped in a thunk to nicely handle circular dependencies
;; between (gnu packages linux) and this module. Additionally, memoize
;; the result to play well with further memoization and code that relies
;; on pointer identity; see <https://bugs.gnu.org/30155>.
(package-with-bootstrap-guile
(package (inherit linux-libre-headers)
(arguments `(#:guile ,%bootstrap-guile
#:implicit-inputs? #f
,@(package-arguments linux-libre-headers)))
(native-inputs
`(("perl" ,perl-boot0)
,@%boot0-inputs))))))
(define gnumach-headers-boot0
(package-with-bootstrap-guile
@ -423,18 +427,19 @@
(current-source-location)
#:guile %bootstrap-guile))))
(define (hurd-core-headers-boot0)
"Return the Hurd and Mach headers as well as initial Hurd libraries for
(define hurd-core-headers-boot0
(mlambda ()
"Return the Hurd and Mach headers as well as initial Hurd libraries for
the bootstrap environment."
(package-with-bootstrap-guile
(package (inherit hurd-core-headers)
(arguments `(#:guile ,%bootstrap-guile
,@(package-arguments hurd-core-headers)))
(inputs
`(("gnumach-headers" ,gnumach-headers-boot0)
("hurd-headers" ,hurd-headers-boot0)
("hurd-minimal" ,hurd-minimal-boot0)
,@%boot0-inputs)))))
(package-with-bootstrap-guile
(package (inherit hurd-core-headers)
(arguments `(#:guile ,%bootstrap-guile
,@(package-arguments hurd-core-headers)))
(inputs
`(("gnumach-headers" ,gnumach-headers-boot0)
("hurd-headers" ,hurd-headers-boot0)
("hurd-minimal" ,hurd-minimal-boot0)
,@%boot0-inputs))))))
(define* (kernel-headers-boot0 #:optional (system (%current-system)))
(match system

@ -620,6 +620,9 @@ itself.
This is implemented as a breadth-first traversal such that INPUTS is
preserved, and only duplicate propagated inputs are removed."
(define (seen? seen item outputs)
;; FIXME: We're using pointer identity here, which is extremely sensitive
;; to memoization in package-producing procedures; see
;; <https://bugs.gnu.org/30155>.
(match (vhash-assq item seen)
((_ . o) (equal? o outputs))
(_ #f)))