Merge branch 'master' into staging

19 files changed, 196 insertions, 163 deletions

diff --git a/guix/build/compile.scm b/guix/build/compile.scm
index 06ed57c9d7..3781e148ce 100644
--- a/guix/build/compile.scm
+++ b/guix/build/compile.scm
@@ -39,25 +39,32 @@
 ;;;
 ;;; Code:
 
-(define %default-optimizations
-  ;; Default optimization options (equivalent to -O2 on Guile 2.2).
-  (append (if (defined? 'tree-il-default-optimization-options)
-              (tree-il-default-optimization-options) ;Guile 2.2
-              (tree-il-optimizations))               ;Guile 3
-          (if (defined? 'cps-default-optimization-options)
-              (cps-default-optimization-options)  ;Guile 2.2
-              (cps-optimizations))))              ;Guile 3
-
-(define %lightweight-optimizations
-  ;; Lightweight optimizations (like -O0, but with partial evaluation).
-  (let loop ((opts %default-optimizations)
-             (result '()))
-    (match opts
-      (() (reverse result))
-      ((#:partial-eval? _ rest ...)
-       (loop rest `(#t #:partial-eval? ,@result)))
-      ((kw _ rest ...)
-       (loop rest `(#f ,kw ,@result))))))
+(define optimizations-for-level
+  (or (and=> (false-if-exception
+              (resolve-interface '(system base optimize)))
+             (lambda (iface)
+               (module-ref iface 'optimizations-for-level))) ;Guile 3.0
+      (let ()                                                ;Guile 2.2
+        (define %default-optimizations
+          ;; Default optimization options (equivalent to -O2 on Guile 2.2).
+          (append (tree-il-default-optimization-options)
+                  (cps-default-optimization-options)))
+
+        (define %lightweight-optimizations
+          ;; Lightweight optimizations (like -O0, but with partial evaluation).
+          (let loop ((opts %default-optimizations)
+                     (result '()))
+            (match opts
+              (() (reverse result))
+              ((#:partial-eval? _ rest ...)
+               (loop rest `(#t #:partial-eval? ,@result)))
+              ((kw _ rest ...)
+               (loop rest `(#f ,kw ,@result))))))
+
+        (lambda (level)
+          (if (<= level 1)
+              %lightweight-optimizations
+              %default-optimizations)))))
 
 (define (supported-warning-type? type)
   "Return true if TYPE, a symbol, denotes a supported warning type."
@@ -80,8 +87,8 @@
 (define (optimization-options file)
   "Return the default set of optimizations options for FILE."
   (if (string-contains file "gnu/packages/")
-      %lightweight-optimizations                  ;build faster
-      '()))
+      (optimizations-for-level 1)                 ;build faster
+      (optimizations-for-level 3)))
 
 (define (scm->go file)
   "Strip the \".scm\" suffix from FILE, and append \".go\"."
diff --git a/guix/build/qt-utils.scm b/guix/build/qt-utils.scm
index 48a32674e9..d2486ee86c 100644
--- a/guix/build/qt-utils.scm
+++ b/guix/build/qt-utils.scm
@@ -26,9 +26,9 @@
       (if env-val (string-append env-val ":" path) path)))
 
   (let ((qml-path        (suffix "QML2_IMPORT_PATH"
-                                 (string-append out "/qml")))
+                                 (string-append out "/lib/qt5/qml")))
         (plugin-path     (suffix "QT_PLUGIN_PATH"
-                                 (string-append out "/plugins")))
+                                 (string-append out "/lib/qt5/plugins")))
         (xdg-data-path   (suffix "XDG_DATA_DIRS"
                                  (string-append out "/share")))
         (xdg-config-path (suffix "XDG_CONFIG_DIRS"
diff --git a/guix/import/texlive.scm b/guix/import/texlive.scm
index 791b514485..d528aace9a 100644
--- a/guix/import/texlive.scm
+++ b/guix/import/texlive.scm
@@ -140,7 +140,9 @@ expression describing it."
            (synopsis   (sxml-value '(entry caption *text*)))
            (version    (or (sxml-value '(entry version @ number *text*))
                            (sxml-value '(entry version @ date *text*))))
-           (license    (string->license (sxml-value '(entry license @ type *text*))))
+           (license    (match ((sxpath '(entry license @ type *text*)) sxml)
+                         ((license) (string->license license))
+                         ((lst ...) (map string->license lst))))
            (home-page  (string-append "http://www.ctan.org/pkg/" id))
            (ref        (texlive-ref component id))
            (checkout   (download-svn-to-store store ref)))
@@ -169,7 +171,9 @@ expression describing it."
                                 (sxml->string (or (sxml-value '(entry description))
                                                   '())))
                                #\newline)))))
-         (license ,license)))))
+         (license ,(match license
+                     ((lst ...) `(list ,@lst))
+                     (license license)))))))
 
 (define texlive->guix-package
   (memoize
diff --git a/guix/profiles.scm b/guix/profiles.scm
index cd3b21e390..f5e5cc33d6 100644
--- a/guix/profiles.scm
+++ b/guix/profiles.scm
@@ -92,6 +92,7 @@
             manifest-pattern-version
             manifest-pattern-output
 
+            concatenate-manifests
             manifest-remove
             manifest-add
             manifest-lookup
@@ -515,6 +516,10 @@ procedure is here for backward-compatibility and will eventually vanish."
   "Return the packages listed in MANIFEST."
   (sexp->manifest (read port)))
 
+(define (concatenate-manifests lst)
+  "Concatenate the manifests listed in LST and return the resulting manifest."
+  (manifest (append-map manifest-entries lst)))
+
 (define (entry-predicate pattern)
   "Return a procedure that returns #t when passed a manifest entry that
 matches NAME/OUTPUT/VERSION.  OUTPUT and VERSION may be #f, in which case they
diff --git a/guix/scripts/archive.scm b/guix/scripts/archive.scm
index fba0f73826..3318ef0889 100644
--- a/guix/scripts/archive.scm
+++ b/guix/scripts/archive.scm
@@ -55,7 +55,7 @@
   ;; Alist of default option values.
   `((system . ,(%current-system))
     (substitutes? . #t)
-    (build-hook? . #t)
+    (offload? . #t)
     (graft? . #t)
     (print-build-trace? . #t)
     (print-extended-build-trace? . #t)
diff --git a/guix/scripts/build.scm b/guix/scripts/build.scm
index ae78df9c5c..a853ac6c7d 100644
--- a/guix/scripts/build.scm
+++ b/guix/scripts/build.scm
@@ -504,7 +504,7 @@ options handled by 'set-build-options-from-command-line', and listed in
   (display (G_ "
       --no-grafts        do not graft packages"))
   (display (G_ "
-      --no-build-hook    do not attempt to offload builds via the build hook"))
+      --no-offload       do not attempt to offload builds"))
   (display (G_ "
       --max-silent-time=SECONDS
                          mark the build as failed after SECONDS of silence"))
@@ -545,7 +545,8 @@ talking to a remote daemon\n")))
                      #:fallback? (assoc-ref opts 'fallback?)
                      #:use-substitutes? (assoc-ref opts 'substitutes?)
                      #:substitute-urls (assoc-ref opts 'substitute-urls)
-                     #:use-build-hook? (assoc-ref opts 'build-hook?)
+                     #:offload? (and (assoc-ref opts 'offload?)
+                                     (not (assoc-ref opts 'keep-failed?)))
                      #:max-silent-time (assoc-ref opts 'max-silent-time)
                      #:timeout (assoc-ref opts 'timeout)
                      #:print-build-trace (assoc-ref opts 'print-build-trace?)
@@ -610,11 +611,15 @@ talking to a remote daemon\n")))
                          (alist-cons 'graft? #f
                                      (alist-delete 'graft? result eq?))
                          rest)))
-        (option '("no-build-hook") #f #f
+        (option '("no-offload" "no-build-hook") #f #f
                 (lambda (opt name arg result . rest)
+                  (when (string=? name "no-build-hook")
+                    (warning (G_ "'--no-build-hook' is deprecated; \
+use '--no-offload' instead~%")))
+
                   (apply values
-                         (alist-cons 'build-hook? #f
-                                     (alist-delete 'build-hook? result))
+                         (alist-cons 'offload? #f
+                                     (alist-delete 'offload? result))
                          rest)))
         (option '("max-silent-time") #t #f
                 (lambda (opt name arg result . rest)
@@ -659,7 +664,7 @@ talking to a remote daemon\n")))
   `((build-mode . ,(build-mode normal))
     (graft? . #t)
     (substitutes? . #t)
-    (build-hook? . #t)
+    (offload? . #t)
     (print-build-trace? . #t)
     (print-extended-build-trace? . #t)
     (multiplexed-build-output? . #t)
diff --git a/guix/scripts/copy.scm b/guix/scripts/copy.scm
index ce70f2f0b3..664cb32b7c 100644
--- a/guix/scripts/copy.scm
+++ b/guix/scripts/copy.scm
@@ -158,7 +158,7 @@ Copy ITEMS to or from the specified host over SSH.\n"))
 (define %default-options
   `((system . ,(%current-system))
     (substitutes? . #t)
-    (build-hook? . #t)
+    (offload? . #t)
     (graft? . #t)
     (print-build-trace? . #t)
     (print-extended-build-trace? . #t)
diff --git a/guix/scripts/deploy.scm b/guix/scripts/deploy.scm
index 27b7e4fd1c..bc0ceabd3f 100644
--- a/guix/scripts/deploy.scm
+++ b/guix/scripts/deploy.scm
@@ -84,7 +84,7 @@ Perform the deployment specified by FILE.\n"))
     (debug . 0)
     (graft? . #t)
     (substitutes? . #t)
-    (build-hook? . #t)
+    (offload? . #t)
     (print-build-trace? . #t)
     (print-extended-build-trace? . #t)
     (multiplexed-build-output? . #t)))
diff --git a/guix/scripts/environment.scm b/guix/scripts/environment.scm
index d78ca0f303..f04363750e 100644
--- a/guix/scripts/environment.scm
+++ b/guix/scripts/environment.scm
@@ -191,7 +191,7 @@ COMMAND or an interactive shell in that environment.\n"))
 (define %default-options
   `((system . ,(%current-system))
     (substitutes? . #t)
-    (build-hook? . #t)
+    (offload? . #t)
     (graft? . #t)
     (print-build-trace? . #t)
     (print-extended-build-trace? . #t)
diff --git a/guix/scripts/offload.scm b/guix/scripts/offload.scm
index 1384f6b41d..18473684eb 100644
--- a/guix/scripts/offload.scm
+++ b/guix/scripts/offload.scm
@@ -60,7 +60,7 @@
 ;;; retrieving the build output(s) over SSH upon success.
 ;;;
 ;;; This command should not be used directly; instead, it is called on-demand
-;;; by the daemon, unless it was started with '--no-build-hook' or a client
+;;; by the daemon, unless it was started with '--no-offload' or a client
 ;;; inhibited build hooks.
 ;;;
 ;;; Code:
diff --git a/guix/scripts/pack.scm b/guix/scripts/pack.scm
index 89b3e389fc..61d18e2609 100644
--- a/guix/scripts/pack.scm
+++ b/guix/scripts/pack.scm
@@ -759,7 +759,7 @@ last resort for relocation."
     (profile-name . "guix-profile")
     (system . ,(%current-system))
     (substitutes? . #t)
-    (build-hook? . #t)
+    (offload? . #t)
     (graft? . #t)
     (print-build-trace? . #t)
     (print-extended-build-trace? . #t)
@@ -965,7 +965,10 @@ Create a bundle of PACKAGE.\n"))
                                   (list (transform store package) "out")))
                                (reverse
                                 (filter-map maybe-package-argument opts))))
-           (manifest-file (assoc-ref opts 'manifest)))
+           (manifests     (filter-map (match-lambda
+                                        (('manifest . file) file)
+                                        (_ #f))
+                                      opts)))
       (define properties
         (if (assoc-ref opts 'save-provenance?)
             (lambda (package)
@@ -979,11 +982,15 @@ Create a bundle of PACKAGE.\n"))
             (const '())))
 
       (cond
-       ((and manifest-file (not (null? packages)))
+       ((and (not (null? manifests)) (not (null? packages)))
         (leave (G_ "both a manifest and a package list were given~%")))
-       (manifest-file
-        (let ((user-module (make-user-module '((guix profiles) (gnu)))))
-          (load* manifest-file user-module)))
+       ((not (null? manifests))
+        (concatenate-manifests
+         (map (lambda (file)
+                (let ((user-module (make-user-module
+                                    '((guix profiles) (gnu)))))
+                  (load* file user-module)))
+              manifests)))
        (else
         (manifest
          (map (match-lambda
diff --git a/guix/scripts/package.scm b/guix/scripts/package.scm
index bcd03a1df9..97436feee7 100644
--- a/guix/scripts/package.scm
+++ b/guix/scripts/package.scm
@@ -318,7 +318,7 @@ Alternately, see @command{guix package --search-paths -p ~s}.")
     (debug . 0)
     (graft? . #t)
     (substitutes? . #t)
-    (build-hook? . #t)
+    (offload? . #t)
     (print-build-trace? . #t)
     (print-extended-build-trace? . #t)
     (multiplexed-build-output? . #t)))
@@ -832,32 +832,17 @@ processed, #f otherwise."
   (unless dry-run?
     (delete-matching-generations store profile pattern)))
 
-(define* (manifest-action store profile file opts
-                          #:key dry-run?)
-  "Change PROFILE to contain the packages specified in FILE."
-  (let* ((user-module  (make-user-module '((guix profiles) (gnu))))
-         (manifest     (load* file user-module))
-         (bootstrap?   (assoc-ref opts 'bootstrap?))
-         (substitutes? (assoc-ref opts 'substitutes?))
-         (allow-collisions? (assoc-ref opts 'allow-collisions?)))
-    (if dry-run?
-        (format #t (G_ "would install new manifest from '~a' with ~d entries~%")
-                file (length (manifest-entries manifest)))
-        (format #t (G_ "installing new manifest from '~a' with ~d entries~%")
-                file (length (manifest-entries manifest))))
-    (build-and-use-profile store profile manifest
-                           #:allow-collisions? allow-collisions?
-                           #:bootstrap? bootstrap?
-                           #:use-substitutes? substitutes?
-                           #:dry-run? dry-run?)))
+(define (load-manifest file)
+  "Load the user-profile manifest (Scheme code) from FILE and return it."
+  (let ((user-module (make-user-module '((guix profiles) (gnu)))))
+    (load* file user-module)))
 
 (define %actions
   ;; List of actions that may be processed.  The car of each pair is the
   ;; action's symbol in the option list; the cdr is the action's procedure.
   `((roll-back? . ,roll-back-action)
     (switch-generation . ,switch-generation-action)
-    (delete-generations . ,delete-generations-action)
-    (manifest . ,manifest-action)))
+    (delete-generations . ,delete-generations-action)))
 
 (define (process-actions store opts)
   "Process any install/remove/upgrade action from OPTS."
@@ -896,7 +881,13 @@ processed, #f otherwise."
               opts)
 
     ;; Then, process normal package removal/installation/upgrade.
-    (let* ((manifest (profile-manifest profile))
+    (let* ((files    (filter-map (match-lambda
+                                   (('manifest . file) file)
+                                   (_ #f))
+                                 opts))
+           (manifest (match files
+                       (() (profile-manifest profile))
+                       (_  (concatenate-manifests (map load-manifest files)))))
            (step1    (options->removable opts manifest
                                          (manifest-transaction)))
            (step2    (options->installable opts manifest step1))
@@ -904,12 +895,23 @@ processed, #f otherwise."
                       (inherit step2)
                       (install (map transform-entry
                                     (manifest-transaction-install step2)))))
-           (new      (manifest-perform-transaction manifest step3)))
+           (new      (manifest-perform-transaction manifest step3))
+           (trans    (if (null? files)
+                         step3
+                         (fold manifest-transaction-install-entry
+                               step3
+                               (manifest-entries manifest)))))
 
       (warn-about-old-distro)
 
-      (unless (manifest-transaction-null? step3)
-        (show-manifest-transaction store manifest step3
+      (unless (manifest-transaction-null? trans)
+        ;; When '--manifest' is used, display information about TRANS as if we
+        ;; were starting from an empty profile.
+        (show-manifest-transaction store
+                                   (if (null? files)
+                                       manifest
+                                       (make-manifest '()))
+                                   trans
                                    #:dry-run? dry-run?)
         (build-and-use-profile store profile new
                                #:allow-collisions? allow-collisions?
diff --git a/guix/scripts/pull.scm b/guix/scripts/pull.scm
index ef8d5c8fd9..a74776bd7b 100644
--- a/guix/scripts/pull.scm
+++ b/guix/scripts/pull.scm
@@ -71,7 +71,7 @@
   ;; Alist of default option values.
   `((system . ,(%current-system))
     (substitutes? . #t)
-    (build-hook? . #t)
+    (offload? . #t)
     (print-build-trace? . #t)
     (print-extended-build-trace? . #t)
     (multiplexed-build-output? . #t)
diff --git a/guix/scripts/substitute.scm b/guix/scripts/substitute.scm
index dba08edf50..ba2fb291d8 100755
--- a/guix/scripts/substitute.scm
+++ b/guix/scripts/substitute.scm
@@ -86,6 +86,8 @@
             read-narinfo
             write-narinfo
 
+            %allow-unauthenticated-substitutes?
+
             substitute-urls
             guix-substitute))
 
@@ -118,15 +120,21 @@
           (string-append %state-directory "/substitute/cache"))
       (string-append (cache-directory #:ensure? #f) "/substitute")))
 
+(define (warn-about-missing-authentication)
+  (warning (G_ "authentication and authorization of substitutes \
+disabled!~%"))
+  #t)
+
 (define %allow-unauthenticated-substitutes?
   ;; Whether to allow unchecked substitutes.  This is useful for testing
   ;; purposes, and should be avoided otherwise.
-  (and (and=> (getenv "GUIX_ALLOW_UNAUTHENTICATED_SUBSTITUTES")
-              (cut string-ci=? <> "yes"))
-       (begin
-         (warning (G_ "authentication and authorization of substitutes \
-disabled!~%"))
-         #t)))
+  (make-parameter
+   (and=> (getenv "GUIX_ALLOW_UNAUTHENTICATED_SUBSTITUTES")
+          (cut string-ci=? <> "yes"))
+   (lambda (value)
+     (when value
+       (warn-about-missing-authentication))
+     value)))
 
 (define %narinfo-ttl
   ;; Number of seconds during which cached narinfo lookups are considered
@@ -227,58 +235,6 @@ provide."
      (leave (G_ "unsupported substitute URI scheme: ~a~%")
             (uri->string uri)))))
 
-(define-record-type <cache-info>
-  (%make-cache-info url store-directory wants-mass-query?)
-  cache-info?
-  (url               cache-info-url)
-  (store-directory   cache-info-store-directory)
-  (wants-mass-query? cache-info-wants-mass-query?))
-
-(define (download-cache-info url)
-  "Download the information for the cache at URL.  On success, return a
-<cache-info> object and a port on which to send further HTTP requests.  On
-failure, return #f and #f."
-  (define uri
-    (string->uri (string-append url "/nix-cache-info")))
-
-  (define (read-cache-info port)
-    (alist->record (fields->alist port)
-                   (cut %make-cache-info url <...>)
-                   '("StoreDir" "WantMassQuery")))
-
-  (catch #t
-    (lambda ()
-      (case (uri-scheme uri)
-        ((file)
-         (values (call-with-input-file (uri-path uri)
-                   read-cache-info)
-                 #f))
-        ((http https)
-         (let ((port (guix:open-connection-for-uri
-                      uri
-                      #:verify-certificate? #f
-                      #:timeout %fetch-timeout)))
-           (guard (c ((http-get-error? c)
-                      (warning (G_ "while fetching '~a': ~a (~s)~%")
-                               (uri->string (http-get-error-uri c))
-                               (http-get-error-code c)
-                               (http-get-error-reason c))
-                      (close-connection port)
-                      (warning (G_ "ignoring substitute server at '~s'~%") url)
-                      (values #f #f)))
-             (values (read-cache-info (http-fetch uri
-                                                  #:verify-certificate? #f
-                                                  #:port port
-                                                  #:keep-alive? #t))
-                     port))))))
-    (lambda (key . args)
-      (case key
-        ((getaddrinfo-error system-error)
-         ;; Silently ignore the error: probably due to lack of network access.
-         (values #f #f))
-        (else
-         (apply throw key args))))))
-
 
 (define-record-type <narinfo>
   (%make-narinfo path uri-base uris compressions file-sizes file-hashes
@@ -422,7 +378,7 @@ No authentication and authorization checks are performed here!"
 (define* (valid-narinfo? narinfo #:optional (acl (current-acl))
                          #:key verbose?)
   "Return #t if NARINFO's signature is not valid."
-  (or %allow-unauthenticated-substitutes?
+  (or (%allow-unauthenticated-substitutes?)
       (let ((hash      (narinfo-sha256 narinfo))
             (signature (narinfo-signature narinfo))
             (uri       (uri->string (first (narinfo-uris narinfo)))))
@@ -628,6 +584,41 @@ if file doesn't exist, and the narinfo otherwise."
           #f
           (apply throw args)))))
 
+(define %unreachable-hosts
+  ;; Set of names of unreachable hosts.
+  (make-hash-table))
+
+(define* (open-connection-for-uri/maybe uri
+                                        #:key
+                                        (verify-certificate? #f)
+                                        (time %fetch-timeout))
+  "Open a connection to URI and return a port to it, or, if connection failed,
+print a warning and return #f."
+  (define host
+    (uri-host uri))
+
+  (catch #t
+    (lambda ()
+      (guix:open-connection-for-uri uri
+                                    #:verify-certificate? verify-certificate?
+                                    #:timeout time))
+    (match-lambda*
+      (('getaddrinfo-error error)
+       (unless (hash-ref %unreachable-hosts host)
+         (hash-set! %unreachable-hosts host #t)   ;warn only once
+         (warning (G_ "~a: host not found: ~a~%")
+                  host (gai-strerror error)))
+       #f)
+      (('system-error . args)
+       (unless (hash-ref %unreachable-hosts host)
+         (hash-set! %unreachable-hosts host #t)
+         (warning (G_ "~a: connection failed: ~a~%") host
+                  (strerror
+                   (system-error-errno `(system-error ,@args)))))
+       #f)
+      (args
+       (apply throw args)))))
+
 (define (fetch-narinfos url paths)
   "Retrieve all the narinfos for PATHS from the cache at URL and return them."
   (define update-progress!
@@ -657,13 +648,18 @@ if file doesn't exist, and the narinfo otherwise."
            (len    (response-content-length response))
            (cache  (response-cache-control response))
            (ttl    (and cache (assoc-ref cache 'max-age))))
+      (update-progress!)
+
       ;; Make sure to read no more than LEN bytes since subsequent bytes may
       ;; belong to the next response.
       (if (= code 200)                            ; hit
           (let ((narinfo (read-narinfo port url #:size len)))
-            (cache-narinfo! url (narinfo-path narinfo) narinfo ttl)
-            (update-progress!)
-            (cons narinfo result))
+            (if (string=? (dirname (narinfo-path narinfo))
+                          (%store-prefix))
+                (begin
+                  (cache-narinfo! url (narinfo-path narinfo) narinfo ttl)
+                  (cons narinfo result))
+                result))
           (let* ((path      (uri-path (request-uri request)))
                  (hash-part (basename
                              (string-drop-right path 8)))) ;drop ".narinfo"
@@ -674,26 +670,28 @@ if file doesn't exist, and the narinfo otherwise."
                             (if (= 404 code)
                                 ttl
                                 %narinfo-transient-error-ttl))
-            (update-progress!)
             result))))
 
-  (define (do-fetch uri port)
+  (define (do-fetch uri)
     (case (and=> uri uri-scheme)
       ((http https)
        (let ((requests (map (cut narinfo-request url <>) paths)))
-         (update-progress!)
-
-         ;; Note: Do not check HTTPS server certificates to avoid depending on
-         ;; the X.509 PKI.  We can do it because we authenticate narinfos,
-         ;; which provides a much stronger guarantee.
-         (let ((result (http-multiple-get uri
-                                          handle-narinfo-response '()
-                                          requests
-                                          #:verify-certificate? #f
-                                          #:port port)))
-           (close-connection port)
-           (newline (current-error-port))
-           result)))
+         (match (open-connection-for-uri/maybe uri)
+           (#f
+            '())
+           (port
+            (update-progress!)
+            ;; Note: Do not check HTTPS server certificates to avoid depending
+            ;; on the X.509 PKI.  We can do it because we authenticate
+            ;; narinfos, which provides a much stronger guarantee.
+            (let ((result (http-multiple-get uri
+                                             handle-narinfo-response '()
+                                             requests
+                                             #:verify-certificate? #f
+                                             #:port port)))
+              (close-port port)
+              (newline (current-error-port))
+              result)))))
       ((file #f)
        (let* ((base  (string-append (uri-path uri) "/"))
               (files (map (compose (cut string-append base <> ".narinfo")
@@ -704,17 +702,7 @@ if file doesn't exist, and the narinfo otherwise."
        (leave (G_ "~s: unsupported server URI scheme~%")
               (if uri (uri-scheme uri) url)))))
 
-  (let-values (((cache-info port)
-                (download-cache-info url)))
-    (and cache-info
-         (if (string=? (cache-info-store-directory cache-info)
-                       (%store-prefix))
-             (do-fetch (string->uri url) port)    ;reuse PORT
-             (begin
-               (warning (G_ "'~a' uses different store '~a'; ignoring it~%")
-                        url (cache-info-store-directory cache-info))
-               (close-connection port)
-               #f)))))
+  (do-fetch (string->uri url)))
 
 (define (lookup-narinfos cache paths)
   "Return the narinfos for PATHS, invoking the server at CACHE when no
diff --git a/guix/scripts/system.scm b/guix/scripts/system.scm
index 27b014db68..e49c9d36b9 100644
--- a/guix/scripts/system.scm
+++ b/guix/scripts/system.scm
@@ -1013,7 +1013,7 @@ Some ACTIONS support additional ARGS.\n"))
   ;; Alist of default option values.
   `((system . ,(%current-system))
     (substitutes? . #t)
-    (build-hook? . #t)
+    (offload? . #t)
     (print-build-trace? . #t)
     (print-extended-build-trace? . #t)
     (multiplexed-build-output? . #t)
diff --git a/guix/scripts/time-machine.scm b/guix/scripts/time-machine.scm
index 19e635555a..1e800e160f 100644
--- a/guix/scripts/time-machine.scm
+++ b/guix/scripts/time-machine.scm
@@ -94,7 +94,7 @@ Execute COMMAND ARGS... in an older version of Guix.\n"))
   ;; Alist of default option values.
   `((system . ,(%current-system))
     (substitutes? . #t)
-    (build-hook? . #t)
+    (offload? . #t)
     (print-build-trace? . #t)
     (print-extended-build-trace? . #t)
     (multiplexed-build-output? . #t)
diff --git a/guix/store.scm b/guix/store.scm
index a276554a52..cf25d347fc 100644
--- a/guix/store.scm
+++ b/guix/store.scm
@@ -763,7 +763,8 @@ encoding conversion errors."
                             max-build-jobs
                             timeout
                             max-silent-time
-                            (use-build-hook? #t)
+                            (offload? #t)
+                            (use-build-hook? *unspecified*) ;deprecated
                             (build-verbosity 0)
                             (log-type 0)
                             (print-build-trace #t)
@@ -803,6 +804,10 @@ encoding conversion errors."
   (define socket
     (store-connection-socket server))
 
+  (unless (unspecified? use-build-hook?)
+    (warn-about-deprecation #:use-build-hook? #f
+                            #:replacement #:offload?))
+
   (let-syntax ((send (syntax-rules ()
                        ((_ (type option) ...)
                         (begin
@@ -816,7 +821,9 @@ encoding conversion errors."
             (max-silent-time (or max-silent-time 3600)))
         (send (integer max-build-jobs) (integer max-silent-time))))
     (when (>= (store-connection-minor-version server) 2)
-      (send (boolean use-build-hook?)))
+      (send (boolean (if (unspecified? use-build-hook?)
+                         offload?
+                         use-build-hook?))))
     (when (>= (store-connection-minor-version server) 4)
       (send (integer build-verbosity) (integer log-type)
             (boolean print-build-trace)))
diff --git a/guix/ui.scm b/guix/ui.scm
index eb17d274c8..12611cb2bc 100644
--- a/guix/ui.scm
+++ b/guix/ui.scm
@@ -372,7 +372,7 @@ ARGS is the list of arguments received by the 'throw' handler."
        (report-error loc (G_ "~a~%") message)))
     (('unbound-variable _ ...)
      (report-unbound-variable-error args #:frame frame))
-    (('srfi-34 obj)
+    (((or 'srfi-34 '%exception) obj)
      (if (message-condition? obj)
          (report-error (and (error-location? obj)
                             (error-location obj))
@@ -404,7 +404,7 @@ exiting.  ARGS is the list of arguments received by the 'throw' handler."
        (warning loc (G_ "~a~%") message)))
     (('unbound-variable _ ...)
      (report-unbound-variable-error args))
-    (('srfi-34 obj)
+    (((or 'srfi-34 '%exception) obj)
      (if (message-condition? obj)
          (warning (G_ "failed to load '~a': ~a~%")
                   file
@@ -813,7 +813,7 @@ similar."
         (match args
           (('syntax-error proc message properties form . rest)
            (report-error (G_ "syntax error: ~a~%") message))
-          (('srfi-34 obj)
+          (((or 'srfi-34 '%exception) obj)
            (if (message-condition? obj)
                (report-error (G_ "~a~%")
                              (gettext (condition-message obj)
diff --git a/guix/utils.scm b/guix/utils.scm
index 64853f2989..728039fbf0 100644
--- a/guix/utils.scm
+++ b/guix/utils.scm
@@ -78,6 +78,8 @@
             package-name->name+version
             target-mingw?
             target-arm32?
+            target-aarch64?
+            target-arm?
             target-64bit?
             version-compare
             version>?
@@ -494,6 +496,12 @@ a character other than '@'."
 (define (target-arm32?)
   (string-prefix? "arm" (or (%current-target-system) (%current-system))))
 
+(define (target-aarch64?)
+  (string-prefix? "aarch64" (or (%current-target-system) (%current-system))))
+
+(define (target-arm?)
+  (or (target-arm32?) (target-aarch64?)))
+
 (define (target-64bit?)
   (let ((system (or (%current-target-system) (%current-system))))
     (any (cut string-prefix? <> system) '("x86_64" "aarch64" "mips64" "ppc64"))))