Merge branch 'core-updates'

28 files changed, 529 insertions, 312 deletions

diff --git a/guix/build-system/cmake.scm b/guix/build-system/cmake.scm
index 0425e9fb39..2e6784251e 100644
--- a/guix/build-system/cmake.scm
+++ b/guix/build-system/cmake.scm
@@ -1,5 +1,5 @@
 ;;; GNU Guix --- Functional package management for GNU
-;;; Copyright © 2013, 2014 Ludovic Courtès <ludo@gnu.org>
+;;; Copyright © 2013, 2014, 2015 Ludovic Courtès <ludo@gnu.org>
 ;;; Copyright © 2013 Cyril Roelandt <tipecaml@gmail.com>
 ;;;
 ;;; This file is part of GNU Guix.
@@ -25,7 +25,8 @@
   #:use-module (guix build-system gnu)
   #:use-module (guix packages)
   #:use-module (ice-9 match)
-  #:export (cmake-build
+  #:export (%cmake-build-system-modules
+            cmake-build
             cmake-build-system))
 
 ;; Commentary:
@@ -35,6 +36,11 @@
 ;;
 ;; Code:
 
+(define %cmake-build-system-modules
+  ;; Build-side modules imported by default.
+  `((guix build cmake-build-system)
+    ,@%gnu-build-system-modules))
+
 (define (default-cmake)
   "Return the default CMake package."
 
@@ -86,9 +92,7 @@
                       (phases '(@ (guix build cmake-build-system)
                                   %standard-phases))
                       (system (%current-system))
-                      (imported-modules '((guix build cmake-build-system)
-                                          (guix build gnu-build-system)
-                                          (guix build utils)))
+                      (imported-modules %cmake-build-system-modules)
                       (modules '((guix build cmake-build-system)
                                  (guix build utils))))
   "Build SOURCE using CMAKE, and with INPUTS. This assumes that SOURCE
diff --git a/guix/build-system/glib-or-gtk.scm b/guix/build-system/glib-or-gtk.scm
index 7a90587136..85d01961a5 100644
--- a/guix/build-system/glib-or-gtk.scm
+++ b/guix/build-system/glib-or-gtk.scm
@@ -1,5 +1,5 @@
 ;;; GNU Guix --- Functional package management for GNU
-;;; Copyright © 2013, 2014 Ludovic Courtès <ludo@gnu.org>
+;;; Copyright © 2013, 2014, 2015 Ludovic Courtès <ludo@gnu.org>
 ;;; Copyright © 2013 Cyril Roelandt <tipecaml@gmail.com>
 ;;; Copyright © 2014 Federico Beffa <beffa@fbengineering.ch>
 ;;;
@@ -26,7 +26,8 @@
   #:use-module (guix build-system gnu)
   #:use-module (guix packages)
   #:use-module (ice-9 match)
-  #:export (glib-or-gtk-build
+  #:export (%glib-or-gtk-build-system-modules
+            glib-or-gtk-build
             glib-or-gtk-build-system))
 
 ;; Commentary:
@@ -67,11 +68,10 @@
   '((guix build glib-or-gtk-build-system)
     (guix build utils)))
 
-(define %default-imported-modules
+(define %glib-or-gtk-build-system-modules
   ;; Build-side modules imported and used by default.
-  '((guix build gnu-build-system)
-    (guix build glib-or-gtk-build-system)
-    (guix build utils)))
+  `((guix build glib-or-gtk-build-system)
+    ,@%gnu-build-system-modules))
 
 (define (default-glib)
   "Return the default glib package from which we use
@@ -136,7 +136,7 @@
                                         %standard-phases))
                             (glib-or-gtk-wrap-excluded-outputs ''())
                             (system (%current-system))
-                            (imported-modules %default-imported-modules)
+                            (imported-modules %glib-or-gtk-build-system-modules)
                             (modules %default-modules)
                             allowed-references)
   "Build SOURCE with INPUTS.  See GNU-BUILD for more details."
diff --git a/guix/build-system/gnu.scm b/guix/build-system/gnu.scm
index c91ad2ee0c..3ccdef1328 100644
--- a/guix/build-system/gnu.scm
+++ b/guix/build-system/gnu.scm
@@ -24,7 +24,8 @@
   #:use-module (guix packages)
   #:use-module (srfi srfi-1)
   #:use-module (ice-9 match)
-  #:export (gnu-build
+  #:export (%gnu-build-system-modules
+            gnu-build
             gnu-build-system
             standard-packages
             package-with-explicit-inputs
@@ -41,9 +42,16 @@
 ;;
 ;; Code:
 
-(define %default-modules
+(define %gnu-build-system-modules
   ;; Build-side modules imported and used by default.
   '((guix build gnu-build-system)
+    (guix build utils)
+    (guix build gremlin)
+    (guix elf)))
+
+(define %default-modules
+  ;; Modules in scope in the build-side environment.
+  '((guix build gnu-build-system)
     (guix build utils)))
 
 (define* (package-with-explicit-inputs p inputs
@@ -182,7 +190,7 @@ runs `make distcheck' and whose result is one or more source tarballs."
        (let* ((args (default-keyword-arguments (package-arguments p)
                       `(#:phases #f
                         #:modules ,%default-modules
-                        #:imported-modules ,%default-modules))))
+                        #:imported-modules ,%gnu-build-system-modules))))
          (substitute-keyword-arguments args
            ((#:modules modules)
             `((guix build gnu-dist)
@@ -277,10 +285,11 @@ standard packages used as implicit inputs of the GNU build system."
                     (strip-flags ''("--strip-debug"))
                     (strip-directories ''("lib" "lib64" "libexec"
                                           "bin" "sbin"))
+                    (validate-runpath? #t)
                     (phases '%standard-phases)
                     (locale "en_US.UTF-8")
                     (system (%current-system))
-                    (imported-modules %default-modules)
+                    (imported-modules %gnu-build-system-modules)
                     (modules %default-modules)
                     (substitutable? #t)
                     allowed-references)
@@ -339,6 +348,7 @@ are allowed to refer to."
                   #:parallel-tests? ,parallel-tests?
                   #:patch-shebangs? ,patch-shebangs?
                   #:strip-binaries? ,strip-binaries?
+                  #:validate-runpath? ,validate-runpath?
                   #:strip-flags ,strip-flags
                   #:strip-directories ,strip-directories)))
 
@@ -411,13 +421,12 @@ is one of `host' or `target'."
                           (strip-flags ''("--strip-debug"))
                           (strip-directories ''("lib" "lib64" "libexec"
                                                 "bin" "sbin"))
+                          (validate-runpath? #t)
                           (phases '%standard-phases)
                           (locale "en_US.UTF-8")
                           (system (%current-system))
-                          (imported-modules '((guix build gnu-build-system)
-                                              (guix build utils)))
-                          (modules '((guix build gnu-build-system)
-                                     (guix build utils)))
+                          (imported-modules %gnu-build-system-modules)
+                          (modules %default-modules)
                           (substitutable? #t)
                           allowed-references)
   "Cross-build NAME for TARGET, where TARGET is a GNU triplet.  INPUTS are
@@ -486,6 +495,7 @@ platform."
                     #:parallel-tests? ,parallel-tests?
                     #:patch-shebangs? ,patch-shebangs?
                     #:strip-binaries? ,strip-binaries?
+                    #:validate-runpath? ,validate-runpath?
                     #:strip-flags ,strip-flags
                     #:strip-directories ,strip-directories))))
 
diff --git a/guix/build-system/haskell.scm b/guix/build-system/haskell.scm
index 79faa5a09e..0fbf0b8e75 100644
--- a/guix/build-system/haskell.scm
+++ b/guix/build-system/haskell.scm
@@ -25,7 +25,8 @@
   #:use-module (guix build-system gnu)
   #:use-module (ice-9 match)
   #:use-module (srfi srfi-26)
-  #:export (haskell-build
+  #:export (%haskell-build-system-modules
+            haskell-build
             haskell-build-system))
 
 ;; Commentary:
@@ -35,6 +36,11 @@
 ;;
 ;; Code:
 
+(define %haskell-build-system-modules
+  ;; Build-side modules imported by default.
+  `((guix build haskell-build-system)
+    ,@%gnu-build-system-modules))
+
 (define (default-haskell)
   "Return the default Haskell package."
   ;; Lazily resolve the binding to avoid a circular dependency.
@@ -80,9 +86,7 @@
                         (search-paths '())
                         (system (%current-system))
                         (guile #f)
-                        (imported-modules '((guix build haskell-build-system)
-                                            (guix build gnu-build-system)
-                                            (guix build utils)))
+                        (imported-modules %haskell-build-system-modules)
                         (modules '((guix build haskell-build-system)
                                    (guix build utils))))
   "Build SOURCE using HASKELL, and with INPUTS.  This assumes that SOURCE
diff --git a/guix/build-system/perl.scm b/guix/build-system/perl.scm
index e0f86438a8..7833153676 100644
--- a/guix/build-system/perl.scm
+++ b/guix/build-system/perl.scm
@@ -1,5 +1,5 @@
 ;;; GNU Guix --- Functional package management for GNU
-;;; Copyright © 2013, 2014 Ludovic Courtès <ludo@gnu.org>
+;;; Copyright © 2013, 2014, 2015 Ludovic Courtès <ludo@gnu.org>
 ;;;
 ;;; This file is part of GNU Guix.
 ;;;
@@ -24,7 +24,8 @@
   #:use-module (guix build-system gnu)
   #:use-module (guix packages)
   #:use-module (ice-9 match)
-  #:export (perl-build
+  #:export (%perl-build-system-modules
+            perl-build
             perl-build-system))
 
 ;; Commentary:
@@ -35,6 +36,11 @@
 ;;
 ;; Code:
 
+(define %perl-build-system-modules
+  ;; Build-side modules imported by default.
+  `((guix build perl-build-system)
+    ,@%gnu-build-system-modules))
+
 (define (default-perl)
   "Return the default Perl package."
 
@@ -83,9 +89,7 @@
                      (outputs '("out"))
                      (system (%current-system))
                      (guile #f)
-                     (imported-modules '((guix build perl-build-system)
-                                         (guix build gnu-build-system)
-                                         (guix build utils)))
+                     (imported-modules %perl-build-system-modules)
                      (modules '((guix build perl-build-system)
                                 (guix build utils))))
   "Build SOURCE using PERL, and with INPUTS.  This assumes that SOURCE
diff --git a/guix/build-system/python.scm b/guix/build-system/python.scm
index 37108650d0..d498cf618b 100644
--- a/guix/build-system/python.scm
+++ b/guix/build-system/python.scm
@@ -27,7 +27,8 @@
   #:use-module (guix build-system gnu)
   #:use-module (ice-9 match)
   #:use-module (srfi srfi-26)
-  #:export (package-with-python2
+  #:export (%python-build-system-modules
+            package-with-python2
             python-build
             python-build-system))
 
@@ -38,6 +39,11 @@
 ;;
 ;; Code:
 
+(define %python-build-system-modules
+  ;; Build-side modules imported by default.
+  `((guix build python-build-system)
+    ,@%gnu-build-system-modules))
+
 (define (default-python)
   "Return the default Python package."
   ;; Lazily resolve the binding to avoid a circular dependency.
@@ -132,9 +138,7 @@ prepended to the name."
                        (search-paths '())
                        (system (%current-system))
                        (guile #f)
-                       (imported-modules '((guix build python-build-system)
-                                           (guix build gnu-build-system)
-                                           (guix build utils)))
+                       (imported-modules %python-build-system-modules)
                        (modules '((guix build python-build-system)
                                   (guix build utils))))
   "Build SOURCE using PYTHON, and with INPUTS.  This assumes that SOURCE
diff --git a/guix/build-system/ruby.scm b/guix/build-system/ruby.scm
index 08301ec609..83bc93d901 100644
--- a/guix/build-system/ruby.scm
+++ b/guix/build-system/ruby.scm
@@ -1,6 +1,6 @@
 ;;; GNU Guix --- Functional package management for GNU
 ;;; Copyright © 2014 David Thompson <davet@gnu.org>
-;;; Copyright © 2014 Ludovic Courtès <ludo@gnu.org>
+;;; Copyright © 2014, 2015 Ludovic Courtès <ludo@gnu.org>
 ;;;
 ;;; This file is part of GNU Guix.
 ;;;
@@ -25,9 +25,15 @@
   #:use-module (guix build-system)
   #:use-module (guix build-system gnu)
   #:use-module (ice-9 match)
-  #:export (ruby-build
+  #:export (%ruby-build-system-modules
+            ruby-build
             ruby-build-system))
 
+(define %ruby-build-system-modules
+  ;; Build-side modules imported by default.
+  `((guix build ruby-build-system)
+    ,@%gnu-build-system-modules))
+
 (define (default-ruby)
   "Return the default Ruby package."
   ;; Lazily resolve the binding to avoid a circular dependency.
@@ -72,9 +78,7 @@
                      (search-paths '())
                      (system (%current-system))
                      (guile #f)
-                     (imported-modules '((guix build ruby-build-system)
-                                         (guix build gnu-build-system)
-                                         (guix build utils)))
+                     (imported-modules %ruby-build-system-modules)
                      (modules '((guix build ruby-build-system)
                                 (guix build utils))))
   "Build SOURCE using RUBY and INPUTS."
diff --git a/guix/build-system/waf.scm b/guix/build-system/waf.scm
index 494cb957ac..c67f649fa7 100644
--- a/guix/build-system/waf.scm
+++ b/guix/build-system/waf.scm
@@ -27,7 +27,8 @@
                 #:select (default-python default-python2))
   #:use-module (ice-9 match)
   #:use-module (srfi srfi-26)
-  #:export (waf-build
+  #:export (%waf-build-system-modules
+            waf-build
             waf-build-system))
 
 ;; Commentary:
@@ -38,6 +39,11 @@
 ;;
 ;; Code:
 
+(define %waf-build-system-modules
+  ;; Build-side modules imported by default.
+  `((guix build waf-build-system)
+    ,@%gnu-build-system-modules))
+
 (define* (lower name
                 #:key source inputs native-inputs outputs system target
                 (python (default-python))
@@ -75,9 +81,7 @@
                        (search-paths '())
                        (system (%current-system))
                        (guile #f)
-                       (imported-modules '((guix build waf-build-system)
-                                           (guix build gnu-build-system)
-                                           (guix build utils)))
+                       (imported-modules %waf-build-system-modules)
                        (modules '((guix build waf-build-system)
                                   (guix build utils))))
   "Build SOURCE with INPUTS.  This assumes that SOURCE provides a 'waf' file
diff --git a/guix/build/cmake-build-system.scm b/guix/build/cmake-build-system.scm
index d8d437c653..f57622e0f4 100644
--- a/guix/build/cmake-build-system.scm
+++ b/guix/build/cmake-build-system.scm
@@ -73,8 +73,8 @@
   ;; Everything is as with the GNU Build System except for the `configure'
   ;; and 'check' phases.
   (modify-phases gnu:%standard-phases
-    (replace check check)
-    (replace configure configure)))
+    (replace 'check check)
+    (replace 'configure configure)))
 
 (define* (cmake-build #:key inputs (phases %standard-phases)
                       #:allow-other-keys #:rest args)
diff --git a/guix/build/glib-or-gtk-build-system.scm b/guix/build/glib-or-gtk-build-system.scm
index 40f1bb85fa..15d7de2236 100644
--- a/guix/build/glib-or-gtk-build-system.scm
+++ b/guix/build/glib-or-gtk-build-system.scm
@@ -242,9 +242,9 @@ needed."
 
 (define %standard-phases
   (modify-phases gnu:%standard-phases
-    (add-after install glib-or-gtk-compile-schemas compile-glib-schemas)
-    (add-after install glib-or-gtk-icon-cache generate-icon-cache)
-    (add-after install glib-or-gtk-wrap wrap-all-programs)))
+    (add-after 'install 'glib-or-gtk-compile-schemas compile-glib-schemas)
+    (add-after 'install 'glib-or-gtk-icon-cache generate-icon-cache)
+    (add-after 'install 'glib-or-gtk-wrap wrap-all-programs)))
 
 (define* (glib-or-gtk-build #:key inputs (phases %standard-phases)
                             #:allow-other-keys #:rest args)
diff --git a/guix/build/gnu-build-system.scm b/guix/build/gnu-build-system.scm
index 5ae537150f..c60f8ba162 100644
--- a/guix/build/gnu-build-system.scm
+++ b/guix/build/gnu-build-system.scm
@@ -18,12 +18,15 @@
 
 (define-module (guix build gnu-build-system)
   #:use-module (guix build utils)
+  #:use-module (guix build gremlin)
+  #:use-module (guix elf)
   #:use-module (ice-9 ftw)
   #:use-module (ice-9 match)
   #:use-module (ice-9 regex)
   #:use-module (ice-9 format)
   #:use-module (srfi srfi-1)
   #:use-module (srfi srfi-26)
+  #:use-module (rnrs io ports)
   #:export (%standard-phases
             gnu-build))
 
@@ -398,6 +401,64 @@ makefiles."
                                        strip-directories)))
                          outputs))))
 
+(define (every* pred lst)
+  "This is like 'every', but process all the elements of LST instead of
+stopping as soon as PRED returns false.  This is useful when PRED has side
+effects, such as displaying warnings or error messages."
+  (let loop ((lst    lst)
+             (result #t))
+    (match lst
+      (()
+       result)
+      ((head . tail)
+       (loop tail (and (pred head) result))))))
+
+(define* (validate-runpath #:key
+                           validate-runpath?
+                           (elf-directories '("lib" "lib64" "libexec"
+                                              "bin" "sbin"))
+                           outputs #:allow-other-keys)
+  "When VALIDATE-RUNPATH? is true, validate that all the ELF files in
+ELF-DIRECTORIES have their dependencies found in their 'RUNPATH'.
+
+Since the ELF parser needs to have a copy of files in memory, better run this
+phase after stripping."
+  (define (sub-directory parent)
+    (lambda (directory)
+      (let ((directory (string-append parent "/" directory)))
+        (and (directory-exists? directory) directory))))
+
+  (define (validate directory)
+    (define (file=? file1 file2)
+      (let ((st1 (stat file1))
+            (st2 (stat file2)))
+        (= (stat:ino st1) (stat:ino st2))))
+
+    ;; There are always symlinks from '.so' to '.so.1' and so on, so delete
+    ;; duplicates.
+    (let ((files (delete-duplicates (find-files directory (lambda (file stat)
+                                                            (elf-file? file)))
+                                    file=?)))
+      (format (current-error-port)
+              "validating RUNPATH of ~a binaries in ~s...~%"
+              (length files) directory)
+      (every* validate-needed-in-runpath files)))
+
+  (if validate-runpath?
+      (let ((dirs (append-map (match-lambda
+                                (("debug" . _)
+                                 ;; The "debug" output is full of ELF files
+                                 ;; that are not worth checking.
+                                 '())
+                                ((name . output)
+                                 (filter-map (sub-directory output)
+                                             elf-directories)))
+                              outputs)))
+        (every* validate dirs))
+      (begin
+        (format (current-error-port) "skipping RUNPATH validation~%")
+        #t)))
+
 (define* (validate-documentation-location #:key outputs
                                           #:allow-other-keys)
   "Documentation should go to 'share/info' and 'share/man', not just 'info/'
@@ -477,6 +538,16 @@ DOCUMENTATION-COMPRESSOR-FLAGS."
         (format #t "not compressing documentation~%")
         #t)))
 
+(define* (delete-info-dir-file #:key outputs #:allow-other-keys)
+  "Delete any 'share/info/dir' file from OUTPUTS."
+  (for-each (match-lambda
+          ((output . directory)
+           (let ((info-dir-file (string-append directory "/share/info/dir")))
+             (when (file-exists? info-dir-file)
+               (delete-file info-dir-file)))))
+            outputs)
+  #t)
+
 (define %standard-phases
   ;; Standard build phases, as a list of symbol/procedure pairs.
   (let-syntax ((phases (syntax-rules ()
@@ -486,7 +557,9 @@ DOCUMENTATION-COMPRESSOR-FLAGS."
             patch-source-shebangs configure patch-generated-file-shebangs
             build check install
             patch-shebangs strip
+            validate-runpath
             validate-documentation-location
+            delete-info-dir-file
             compress-documentation)))
 
 
diff --git a/guix/build/gnu-dist.scm b/guix/build/gnu-dist.scm
index 887b5e94e9..ad69c6cf16 100644
--- a/guix/build/gnu-dist.scm
+++ b/guix/build/gnu-dist.scm
@@ -83,10 +83,10 @@
 (define %dist-phases
   ;; Phases for building a source tarball.
   (modify-phases %standard-phases
-    (delete strip)
-    (replace install install-dist)
-    (replace build build)
-    (add-before configure autoreconf autoreconf)
-    (replace unpack copy-source)))
+    (delete 'strip)
+    (replace 'install install-dist)
+    (replace 'build build)
+    (add-before 'configure 'autoreconf autoreconf)
+    (replace 'unpack copy-source)))
 
 ;;; gnu-dist.scm ends here
diff --git a/guix/build/gremlin.scm b/guix/build/gremlin.scm
index e8429129e1..30b06034dd 100644
--- a/guix/build/gremlin.scm
+++ b/guix/build/gremlin.scm
@@ -18,14 +18,22 @@
 
 (define-module (guix build gremlin)
   #:use-module (guix elf)
+  #:use-module ((guix build utils) #:select (store-file-name?))
   #:use-module (ice-9 match)
   #:use-module (srfi srfi-1)
   #:use-module (srfi srfi-9)
   #:use-module (srfi srfi-26)
+  #:use-module (srfi srfi-34)
+  #:use-module (srfi srfi-35)
   #:use-module (system foreign)
   #:use-module (rnrs bytevectors)
   #:use-module (rnrs io ports)
-  #:export (elf-dynamic-info
+  #:export (elf-error?
+            elf-error-elf
+            invalid-segment-size?
+            invalid-segment-size-segment
+
+            elf-dynamic-info
             elf-dynamic-info?
             elf-dynamic-info-sopath
             elf-dynamic-info-needed
@@ -41,12 +49,31 @@
 ;;;
 ;;; Code:
 
+(define-condition-type &elf-error &error
+  elf-error?
+  (elf elf-error-elf))
+
+(define-condition-type &invalid-segment-size &elf-error
+  invalid-segment-size?
+  (segment invalid-segment-size-segment))
+
+
 (define (dynamic-link-segment elf)
   "Return the 'PT_DYNAMIC' segment of ELF--i.e., the segment that contains
 dynamic linking information."
-  (find (lambda (segment)
-          (= (elf-segment-type segment) PT_DYNAMIC))
-        (elf-segments elf)))
+  (let ((size (bytevector-length (elf-bytes elf))))
+    (find (lambda (segment)
+            (unless (<= (+ (elf-segment-offset segment)
+                           (elf-segment-filesz segment))
+                        size)
+              ;; This happens on separate debug output files created by
+              ;; 'strip --only-keep-debug' (Binutils 2.25.)
+              (raise (condition (&invalid-segment-size
+                                 (elf elf)
+                                 (segment segment)))))
+
+            (= (elf-segment-type segment) PT_DYNAMIC))
+          (elf-segments elf))))
 
 (define (word-reader size byte-order)
   "Return a procedure to read a word of SIZE bytes according to BYTE-ORDER."
@@ -197,6 +224,7 @@ value of DT_NEEDED entries is a string.)"
     "libc.so"
     "libdl.so"
     "libm.so"
+    "libnsl.so"                                   ;NEEDED by nscd
     "libpthread.so"
     "libresolv.so"
     "librt.so"
@@ -214,23 +242,42 @@ value of DT_NEEDED entries is a string.)"
 present in its RUNPATH, or if FILE lacks dynamic-link information.  Return #f
 otherwise.  Libraries whose name matches ALWAYS-FOUND? are considered to be
 always available."
-  (let* ((elf     (call-with-input-file file
-                    (compose parse-elf get-bytevector-all)))
-         (dyninfo (elf-dynamic-info elf)))
-    (when dyninfo
-      (let* ((runpath   (elf-dynamic-info-runpath dyninfo))
-             (needed    (remove always-found?
-                                (elf-dynamic-info-needed dyninfo)))
-             (not-found (remove (cut search-path runpath <>)
-                                needed)))
-        (for-each (lambda (lib)
-                    (format (current-error-port)
-                            "error: '~a' depends on '~a', which cannot \
+  (guard (c ((invalid-segment-size? c)
+             (let ((segment (invalid-segment-size-segment c)))
+               (format (current-error-port)
+                       "~a: error: offset + size of segment ~a (type ~a) \
+exceeds total size~%"
+                       file
+                       (elf-segment-index segment)
+                       (elf-segment-type segment))
+               #f)))
+
+    (let* ((elf     (call-with-input-file file
+                      (compose parse-elf get-bytevector-all)))
+           (dyninfo (elf-dynamic-info elf)))
+      (when dyninfo
+        (let* ((runpath   (filter store-file-name?
+                                  (elf-dynamic-info-runpath dyninfo)))
+               (bogus     (remove store-file-name?
+                                  (elf-dynamic-info-runpath dyninfo)))
+               (needed    (remove always-found?
+                                  (elf-dynamic-info-needed dyninfo)))
+               (not-found (remove (cut search-path runpath <>)
+                                  needed)))
+          ;; XXX: $ORIGIN is not supported.
+          (unless (null? bogus)
+            (format (current-error-port)
+                    "~a: warning: RUNPATH contains bogus entries: ~s~%"
+                    file bogus))
+
+          (for-each (lambda (lib)
+                      (format (current-error-port)
+                              "~a: error: depends on '~a', which cannot \
 be found in RUNPATH ~s~%"
-                            file lib runpath))
-                  not-found)
-        ;; (when (null? not-found)
-        ;;   (format (current-error-port) "~a is OK~%" file))
-        (null? not-found)))))
+                              file lib runpath))
+                    not-found)
+          ;; (when (null? not-found)
+          ;;   (format (current-error-port) "~a is OK~%" file))
+          (null? not-found))))))
 
 ;;; gremlin.scm ends here
diff --git a/guix/build/haskell-build-system.scm b/guix/build/haskell-build-system.scm
index e17967fb72..d382ee403d 100644
--- a/guix/build/haskell-build-system.scm
+++ b/guix/build/haskell-build-system.scm
@@ -196,13 +196,13 @@ generate the cache as it would clash in user profiles."
 
 (define %standard-phases
   (modify-phases gnu:%standard-phases
-    (add-before configure setup-compiler setup-compiler)
-    (add-before install haddock haddock)
-    (add-after install register register)
-    (replace install install)
-    (replace check check)
-    (replace build build)
-    (replace configure configure)))
+    (add-before 'configure 'setup-compiler setup-compiler)
+    (add-before 'install 'haddock haddock)
+    (add-after 'install 'register register)
+    (replace 'install install)
+    (replace 'check check)
+    (replace 'build build)
+    (replace 'configure configure)))
 
 (define* (haskell-build #:key inputs (phases %standard-phases)
                         #:allow-other-keys #:rest args)
diff --git a/guix/build/perl-build-system.scm b/guix/build/perl-build-system.scm
index 9ca5353bb9..8f480eae16 100644
--- a/guix/build/perl-build-system.scm
+++ b/guix/build/perl-build-system.scm
@@ -72,10 +72,10 @@
   ;; Everything is as with the GNU Build System except for the `configure',
   ;; `build', `check', and `install' phases.
   (modify-phases gnu:%standard-phases
-    (replace install install)
-    (replace check check)
-    (replace build build)
-    (replace configure configure)))
+    (replace 'install install)
+    (replace 'check check)
+    (replace 'build build)
+    (replace 'configure configure)))
 
 (define* (perl-build #:key inputs (phases %standard-phases)
                      #:allow-other-keys #:rest args)
diff --git a/guix/build/python-build-system.scm b/guix/build/python-build-system.scm
index 9f853134bd..26a7254db9 100644
--- a/guix/build/python-build-system.scm
+++ b/guix/build/python-build-system.scm
@@ -123,12 +123,12 @@ installed with setuptools."
   ;; 'configure' and 'build' phases are not needed.  Everything is done during
   ;; 'install'.
   (modify-phases gnu:%standard-phases
-    (delete configure)
-    (replace install install)
-    (replace check check)
-    (replace build build)
-    (add-after install wrap wrap)
-    (add-before strip rename-pth-file rename-pth-file)))
+    (delete 'configure)
+    (replace 'install install)
+    (replace 'check check)
+    (replace 'build build)
+    (add-after 'install 'wrap wrap)
+    (add-before 'strip 'rename-pth-file rename-pth-file)))
 
 (define* (python-build #:key inputs (phases %standard-phases)
                        #:allow-other-keys #:rest args)
diff --git a/guix/build/ruby-build-system.scm b/guix/build/ruby-build-system.scm
index a143df467f..531cf382ae 100644
--- a/guix/build/ruby-build-system.scm
+++ b/guix/build/ruby-build-system.scm
@@ -72,11 +72,11 @@ directory."
 
 (define %standard-phases
   (modify-phases gnu:%standard-phases
-    (delete configure)
-    (add-after unpack gitify gitify)
-    (replace build build)
-    (replace install install)
-    (replace check check)))
+    (delete 'configure)
+    (add-after 'unpack 'gitify gitify)
+    (replace 'build build)
+    (replace 'install install)
+    (replace 'check check)))
 
 (define* (ruby-build #:key inputs (phases %standard-phases)
                      #:allow-other-keys #:rest args)
diff --git a/guix/build/utils.scm b/guix/build/utils.scm
index a5a6167a8c..676a0120e3 100644
--- a/guix/build/utils.scm
+++ b/guix/build/utils.scm
@@ -32,6 +32,7 @@
   #:re-export (alist-cons
                alist-delete)
   #:export (%store-directory
+            store-file-name?
             parallel-job-count
 
             directory-exists?
@@ -44,6 +45,7 @@
             mkdir-p
             copy-recursively
             delete-file-recursively
+            file-name-predicate
             find-files
 
             search-path-as-list
@@ -80,6 +82,10 @@
   (or (getenv "NIX_STORE")
       "/gnu/store"))
 
+(define (store-file-name? file)
+  "Return true if FILE is in the store."
+  (string-prefix? (%store-directory) file))
+
 (define parallel-job-count
   ;; Number of processes to be passed next to GNU Make's `-j' argument.
   (make-parameter
@@ -263,33 +269,46 @@ errors."
                       ;; Don't follow symlinks.
                       lstat)))
 
-(define (find-files dir regexp)
-  "Return the lexicographically sorted list of files under DIR whose basename
-matches REGEXP."
-  (define file-rx
-    (if (regexp? regexp)
-        regexp
-        (make-regexp regexp)))
-
-  ;; Sort the result to get deterministic results.
-  (sort (file-system-fold (const #t)
-                          (lambda (file stat result)   ; leaf
-                            (if (regexp-exec file-rx (basename file))
-                                (cons file result)
-                                result))
-                          (lambda (dir stat result)    ; down
-                            result)
-                          (lambda (dir stat result)    ; up
-                            result)
-                          (lambda (file stat result)   ; skip
-                            result)
-                          (lambda (file stat errno result)
-                            (format (current-error-port) "find-files: ~a: ~a~%"
-                                    file (strerror errno))
-                            result)
-                          '()
-                          dir)
-        string<?))
+(define (file-name-predicate regexp)
+  "Return a predicate that returns true when passed a file name whose base
+name matches REGEXP."
+  (let ((file-rx (if (regexp? regexp)
+                     regexp
+                     (make-regexp regexp))))
+    (lambda (file stat)
+      (regexp-exec file-rx (basename file)))))
+
+(define* (find-files dir #:optional (pred (const #t))
+                     #:key (stat lstat))
+  "Return the lexicographically sorted list of files under DIR for which PRED
+returns true.  PRED is passed two arguments: the absolute file name, and its
+stat buffer; the default predicate always returns true.  PRED can also be a
+regular expression, in which case it is equivalent to (file-name-predicate
+PRED).  STAT is used to obtain file information; using 'lstat' means that
+symlinks are not followed."
+  (let ((pred (if (procedure? pred)
+                  pred
+                  (file-name-predicate pred))))
+    ;; Sort the result to get deterministic results.
+    (sort (file-system-fold (const #t)
+                            (lambda (file stat result) ; leaf
+                              (if (pred file stat)
+                                  (cons file result)
+                                  result))
+                            (lambda (dir stat result) ; down
+                              result)
+                            (lambda (dir stat result) ; up
+                              result)
+                            (lambda (file stat result) ; skip
+                              result)
+                            (lambda (file stat errno result)
+                              (format (current-error-port) "find-files: ~a: ~a~%"
+                                      file (strerror errno))
+                              result)
+                            '()
+                            dir
+                            stat)
+          string<?)))
 
 
 ;;;
@@ -446,13 +465,13 @@ an expression evaluating to a procedure."
 (define-syntax %modify-phases
   (syntax-rules (delete replace add-before add-after)
     ((_ phases (delete old-phase-name))
-     (alist-delete 'old-phase-name phases))
+     (alist-delete old-phase-name phases))
     ((_ phases (replace old-phase-name new-phase))
-     (alist-replace 'old-phase-name new-phase phases))
+     (alist-replace old-phase-name new-phase phases))
     ((_ phases (add-before old-phase-name new-phase-name new-phase))
-     (alist-cons-before 'old-phase-name 'new-phase-name new-phase phases))
+     (alist-cons-before old-phase-name new-phase-name new-phase phases))
     ((_ phases (add-after old-phase-name new-phase-name new-phase))
-     (alist-cons-after 'old-phase-name 'new-phase-name new-phase phases))))
+     (alist-cons-after old-phase-name new-phase-name new-phase phases))))
 
 
 ;;;
diff --git a/guix/build/waf-build-system.scm b/guix/build/waf-build-system.scm
index d172c5a836..85f0abcfd6 100644
--- a/guix/build/waf-build-system.scm
+++ b/guix/build/waf-build-system.scm
@@ -70,10 +70,10 @@
 
 (define %standard-phases
   (modify-phases gnu:%standard-phases
-    (replace configure configure)
-    (replace build build)
-    (replace check check)
-    (replace install install)))
+    (replace 'configure configure)
+    (replace 'build build)
+    (replace 'check check)
+    (replace 'install install)))
 
 (define* (waf-build #:key inputs (phases %standard-phases)
                        #:allow-other-keys #:rest args)
diff --git a/guix/cvs-download.scm b/guix/cvs-download.scm
index 8a0d479fa4..72478dd2c2 100644
--- a/guix/cvs-download.scm
+++ b/guix/cvs-download.scm
@@ -66,7 +66,7 @@ HASH-ALGO (a symbol).  Use NAME as the file name, or a generic name if #f."
                    '#$(cvs-reference-module ref)
                    '#$(cvs-reference-revision ref)
                    #$output
-                   #:cvs-command (string-append #$cvs "/bin/cvs"))))
+                   #:cvs-command (string-append #+cvs "/bin/cvs"))))
 
   (mlet %store-monad ((guile (package->derivation guile system)))
     (gexp->derivation (or name "cvs-checkout") build
diff --git a/guix/download.scm b/guix/download.scm
index d87d02e2af..3e4024fe1f 100644
--- a/guix/download.scm
+++ b/guix/download.scm
@@ -241,12 +241,12 @@ in the store."
 
   (define builder
     #~(begin
-        #$(if need-gnutls?
+        #+(if need-gnutls?
 
               ;; Add GnuTLS to the inputs and to the load path.
               #~(eval-when (load expand eval)
                   (set! %load-path
-                        (cons (string-append #$(gnutls-package)
+                        (cons (string-append #+(gnutls-package)
                                              "/share/guile/site/"
                                              (effective-version))
                               %load-path)))
diff --git a/guix/git-download.scm b/guix/git-download.scm
index 94a1245480..f4b48d7a6b 100644
--- a/guix/git-download.scm
+++ b/guix/git-download.scm
@@ -76,7 +76,7 @@ HASH-ALGO (a symbol).  Use NAME as the file name, or a generic name if #f."
         ;; The 'git submodule' commands expects Coreutils, sed,
         ;; grep, etc. to be in $PATH.
         (set-path-environment-variable "PATH" '("bin")
-                                       (match '#$inputs
+                                       (match '#+inputs
                                          (((names dirs) ...)
                                           dirs)))
 
@@ -84,7 +84,7 @@ HASH-ALGO (a symbol).  Use NAME as the file name, or a generic name if #f."
                    '#$(git-reference-commit ref)
                    #$output
                    #:recursive? '#$(git-reference-recursive? ref)
-                   #:git-command (string-append #$git "/bin/git"))))
+                   #:git-command (string-append #+git "/bin/git"))))
 
   (mlet %store-monad ((guile (package->derivation guile system)))
     (gexp->derivation (or name "git-checkout") build
diff --git a/guix/packages.scm b/guix/packages.scm
index ec0e79d08b..8ebe8d06b5 100644
--- a/guix/packages.scm
+++ b/guix/packages.scm
@@ -26,6 +26,7 @@
   #:use-module (guix base32)
   #:use-module (guix derivations)
   #:use-module (guix build-system)
+  #:use-module (guix gexp)
   #:use-module (ice-9 match)
   #:use-module (ice-9 vlist)
   #:use-module (srfi srfi-1)
@@ -106,6 +107,7 @@
 
             package->bag
             bag->derivation
+            bag-direct-inputs
             bag-transitive-inputs
             bag-transitive-host-inputs
             bag-transitive-build-inputs
@@ -334,8 +336,10 @@ corresponds to the arguments expected by `set-path-environment-variable'."
       ("bzip2" ,(ref '(gnu packages compression) 'bzip2))
       ("gzip"  ,(ref '(gnu packages compression) 'gzip))
       ("lzip"  ,(ref '(gnu packages compression) 'lzip))
+      ("unzip" ,(ref '(gnu packages zip) 'unzip))
       ("patch" ,(ref '(gnu packages base) 'patch))
-      ("locales" ,(ref '(gnu packages base) 'glibc-utf8-locales)))))
+      ("locales" ,(ref '(gnu packages commencement)
+                       'glibc-utf8-locales-final)))))
 
 (define (default-guile)
   "Return the default Guile package used to run the build code of
@@ -349,10 +353,9 @@ the build code of derivation."
   (package->derivation (default-guile) system
                        #:graft? #f))
 
-;; TODO: Rewrite using %STORE-MONAD and gexps.
-(define* (patch-and-repack store source patches
+(define* (patch-and-repack source patches
                            #:key
-                           (inputs '())
+                           inputs
                            (snippet #f)
                            (flags '("-p1"))
                            (modules '())
@@ -370,10 +373,20 @@ IMPORTED-MODULES specify modules to use/import for use by SNIPPET."
         (derivation->output-path source)
         source))
 
+  (define lookup-input
+    ;; The default value of the 'patch-inputs' field, and thus INPUTS is #f,
+    ;; so deal with that.
+    (let ((inputs (or inputs (%standard-patch-inputs))))
+      (lambda (name)
+        (match (assoc-ref inputs name)
+          ((package) package)
+          (#f        #f)))))
+
   (define decompression-type
     (cond ((string-suffix? "gz" source-file-name)  "gzip")
           ((string-suffix? "bz2" source-file-name) "bzip2")
           ((string-suffix? "lz" source-file-name)  "lzip")
+          ((string-suffix? "zip" source-file-name) "unzip")
           (else "xz")))
 
   (define original-file-name
@@ -398,115 +411,95 @@ IMPORTED-MODULES specify modules to use/import for use by SNIPPET."
                          ".xz"
                          ".tar.xz"))))
 
-  (define patch-inputs
-    (map (lambda (number patch)
-           (list (string-append "patch" (number->string number))
-                 (match patch
-                   ((? string?)
-                    (add-to-store store (basename patch) #t
-                                  "sha256" patch))
-                   ((? origin?)
-                    (package-source-derivation store patch system)))))
-         (iota (length patches))
-
-         patches))
-
-  (define builder
-    `(begin
-       (use-modules (ice-9 ftw)
-                    (srfi srfi-1)
-                    (guix build utils))
-
-       ;; Encoding/decoding errors shouldn't be silent.
-       (fluid-set! %default-port-conversion-strategy 'error)
-
-       (let ((locales (assoc-ref %build-inputs "locales"))
-             (out     (assoc-ref %outputs "out"))
-             (xz      (assoc-ref %build-inputs "xz"))
-             (decomp  (assoc-ref %build-inputs ,decompression-type))
-             (source  (assoc-ref %build-inputs "source"))
-             (tar     (string-append (assoc-ref %build-inputs "tar")
-                                     "/bin/tar"))
-             (patch   (string-append (assoc-ref %build-inputs "patch")
-                                     "/bin/patch")))
-         (define (apply-patch input)
-           (let ((patch* (assoc-ref %build-inputs input)))
-             (format (current-error-port) "applying '~a'...~%" patch*)
-
-             ;; Use '--force' so that patches that do not apply perfectly are
-             ;; rejected.
-             (zero? (system* patch "--force" ,@flags "--input" patch*))))
-
-         (define (first-file directory)
-           ;; Return the name of the first file in DIRECTORY.
-           (car (scandir directory
-                         (lambda (name)
-                           (not (member name '("." "..")))))))
-
-         (when locales
-           ;; First of all, install a UTF-8 locale so that UTF-8 file names
-           ;; are correctly interpreted.  During bootstrap, LOCALES is #f.
-           (setenv "LOCPATH" (string-append locales "/lib/locale"))
-           (setlocale LC_ALL "en_US.UTF-8"))
-
-         (setenv "PATH" (string-append xz "/bin" ":"
-                                       decomp "/bin"))
-
-         ;; SOURCE may be either a directory or a tarball.
-         (and (if (file-is-directory? source)
-                  (let* ((store     (or (getenv "NIX_STORE") "/gnu/store"))
-                         (len       (+ 1 (string-length store)))
-                         (base      (string-drop source len))
-                         (dash      (string-index base #\-))
-                         (directory (string-drop base (+ 1 dash))))
-                    (mkdir directory)
-                    (copy-recursively source directory)
-                    #t)
-                  (zero? (system* tar "xvf" source)))
-              (let ((directory (first-file ".")))
-                (format (current-error-port)
-                        "source is under '~a'~%" directory)
-                (chdir directory)
-
-                (and (every apply-patch ',(map car patch-inputs))
-
-                     ,@(if snippet
-                           `((let ((module (make-fresh-user-module)))
-                               (module-use-interfaces! module
-                                                       (map resolve-interface
-                                                            ',modules))
-                               (module-define! module '%build-inputs
-                                               %build-inputs)
-                               (module-define! module '%outputs %outputs)
-                               ((@ (system base compile) compile)
-                                ',snippet
-                                #:to 'value
-                                #:opts %auto-compilation-options
-                                #:env module)))
-                           '())
-
-                     (begin (chdir "..") #t)
-                     (zero? (system* tar "cvfa" out directory))))))))
-
-
-  (let ((name    (tarxz-name original-file-name))
-        (inputs  (filter-map (match-lambda
-                              ((name (? package? p))
-                               (and (member name (cons decompression-type
-                                                       '("tar" "xz" "patch")))
-                                    (list name
-                                          (package-derivation store p system
-                                                              #:graft? #f)))))
-                             (or inputs (%standard-patch-inputs))))
-        (modules (delete-duplicates (cons '(guix build utils) modules))))
-
-    (build-expression->derivation store name builder
-                                 #:inputs `(("source" ,source)
-                                            ,@inputs
-                                            ,@patch-inputs)
-                                 #:system system
-                                 #:modules modules
-                                 #:guile-for-build guile-for-build)))
+  (define instantiate-patch
+    (match-lambda
+      ((? string? patch)
+       (interned-file patch #:recursive? #t))
+      ((? origin? patch)
+       (origin->derivation patch system))))
+
+  (mlet %store-monad ((tar ->     (lookup-input "tar"))
+                      (xz ->      (lookup-input "xz"))
+                      (patch ->   (lookup-input "patch"))
+                      (locales -> (lookup-input "locales"))
+                      (decomp ->  (lookup-input decompression-type))
+                      (patches    (sequence %store-monad
+                                            (map instantiate-patch patches))))
+    (define build
+      #~(begin
+          (use-modules (ice-9 ftw)
+                       (srfi srfi-1)
+                       (guix build utils))
+
+          (define (apply-patch patch)
+            (format (current-error-port) "applying '~a'...~%" patch)
+
+            ;; Use '--force' so that patches that do not apply perfectly are
+            ;; rejected.
+            (zero? (system* (string-append #+patch "/bin/patch")
+                            "--force" #+@flags "--input" patch)))
+
+          (define (first-file directory)
+            ;; Return the name of the first file in DIRECTORY.
+            (car (scandir directory
+                          (lambda (name)
+                            (not (member name '("." "..")))))))
+
+          ;; Encoding/decoding errors shouldn't be silent.
+          (fluid-set! %default-port-conversion-strategy 'error)
+
+          (when #+locales
+            ;; First of all, install a UTF-8 locale so that UTF-8 file names
+            ;; are correctly interpreted.  During bootstrap, LOCALES is #f.
+            (setenv "LOCPATH" (string-append #+locales "/lib/locale"))
+            (setlocale LC_ALL "en_US.UTF-8"))
+
+          (setenv "PATH" (string-append #+xz "/bin" ":"
+                                        #+decomp "/bin"))
+
+          ;; SOURCE may be either a directory or a tarball.
+          (and (if (file-is-directory? #+source)
+                   (let* ((store     (or (getenv "NIX_STORE") "/gnu/store"))
+                          (len       (+ 1 (string-length store)))
+                          (base      (string-drop #+source len))
+                          (dash      (string-index base #\-))
+                          (directory (string-drop base (+ 1 dash))))
+                     (mkdir directory)
+                     (copy-recursively #+source directory)
+                     #t)
+                   #+(if (string=? decompression-type "unzip")
+                         #~(zero? (system* "unzip" #+source))
+                         #~(zero? (system* (string-append #+tar "/bin/tar")
+                                           "xvf" #+source))))
+               (let ((directory (first-file ".")))
+                 (format (current-error-port)
+                         "source is under '~a'~%" directory)
+                 (chdir directory)
+
+                 (and (every apply-patch '#+patches)
+                      #+@(if snippet
+                             #~((let ((module (make-fresh-user-module)))
+                                  (module-use-interfaces! module
+                                                          (map resolve-interface
+                                                               '#+modules))
+                                  ((@ (system base compile) compile)
+                                   '#+snippet
+                                   #:to 'value
+                                   #:opts %auto-compilation-options
+                                   #:env module)))
+                             #~())
+
+                      (begin (chdir "..") #t)
+                      (zero? (system* (string-append #+tar "/bin/tar")
+                                      "cvfa" #$output directory)))))))
+
+    (let ((name    (tarxz-name original-file-name))
+          (modules (delete-duplicates (cons '(guix build utils) modules))))
+      (gexp->derivation name build
+                        #:graft? #f
+                        #:system system
+                        #:modules modules
+                        #:guile-for-build guile-for-build))))
 
 (define (transitive-inputs inputs)
   (let loop ((inputs  inputs)
@@ -586,13 +579,17 @@ supported by its dependencies."
             (_
              systems)))
         (package-supported-systems package)
-        (package-direct-inputs package)))
+        (bag-direct-inputs (package->bag package))))
+
+(define (bag-direct-inputs bag)
+  "Same as 'package-direct-inputs', but applied to a bag."
+  (append (bag-build-inputs bag)
+          (bag-host-inputs bag)
+          (bag-target-inputs bag)))
 
 (define (bag-transitive-inputs bag)
   "Same as 'package-transitive-inputs', but applied to a bag."
-  (transitive-inputs (append (bag-build-inputs bag)
-                             (bag-host-inputs bag)
-                             (bag-target-inputs bag))))
+  (transitive-inputs (bag-direct-inputs bag)))
 
 (define (bag-transitive-build-inputs bag)
   "Same as 'package-transitive-native-inputs', but applied to a bag."
@@ -954,9 +951,6 @@ cross-compilation target triplet."
       (package->cross-derivation package target system)
       (package->derivation package system)))
 
-(define patch-and-repack*
-  (store-lift patch-and-repack))
-
 (define* (origin->derivation source
                              #:optional (system (%current-system)))
   "When SOURCE is an <origin> object, return its derivation for SYSTEM.  When
@@ -976,14 +970,14 @@ outside of the store) or SOURCE itself (if SOURCE is already a store item.)"
                                                           (default-guile))
                                                       system
                                                       #:graft? #f)))
-       (patch-and-repack* source patches
-                          #:inputs inputs
-                          #:snippet snippet
-                          #:flags flags
-                          #:system system
-                          #:modules modules
-                          #:imported-modules modules
-                          #:guile-for-build guile)))
+       (patch-and-repack source patches
+                         #:inputs inputs
+                         #:snippet snippet
+                         #:flags flags
+                         #:system system
+                         #:modules modules
+                         #:imported-modules modules
+                         #:guile-for-build guile)))
     ((and (? string?) (? direct-store-path?) file)
      (with-monad %store-monad
        (return file)))
diff --git a/guix/scripts/lint.scm b/guix/scripts/lint.scm
index c40d76b558..cced1bda66 100644
--- a/guix/scripts/lint.scm
+++ b/guix/scripts/lint.scm
@@ -19,6 +19,7 @@
 ;;; along with GNU Guix.  If not, see <http://www.gnu.org/licenses/>.
 
 (define-module (guix scripts lint)
+  #:use-module (guix store)
   #:use-module (guix base32)
   #:use-module (guix download)
   #:use-module (guix ftp-client)
@@ -32,6 +33,8 @@
   #:use-module (ice-9 regex)
   #:use-module (ice-9 format)
   #:use-module (web uri)
+  #:use-module (srfi srfi-34)
+  #:use-module (srfi srfi-35)
   #:use-module ((guix build download)
                 #:select (maybe-expand-mirrors
                           open-connection-for-uri))
@@ -41,12 +44,15 @@
   #:use-module (srfi srfi-9)
   #:use-module (srfi srfi-11)
   #:use-module (srfi srfi-26)
+  #:use-module (srfi srfi-34)
+  #:use-module (srfi srfi-35)
   #:use-module (srfi srfi-37)
   #:export (guix-lint
             check-description-style
             check-inputs-should-be-native
-            check-patches
+            check-patch-file-names
             check-synopsis-style
+            check-derivation
             check-home-page
             check-source))
 
@@ -348,26 +354,30 @@ warning for PACKAGE mentionning the FIELD."
                                     (package-home-page package))
                     'home-page)))))
 
-(define (check-patches package)
-  ;; Emit a warning if the patches requires by PACKAGE are badly named.
-  (let ((patches   (and=> (package-source package) origin-patches))
-        (name      (package-name package))
-        (full-name (package-full-name package)))
-    (when (and patches
-               (any (match-lambda
-                     ((? string? patch)
-                      (let ((filename (basename patch)))
-                        (not (or (eq? (string-contains filename name) 0)
-                                 (eq? (string-contains filename full-name)
-                                      0)))))
-                     (_
-                      ;; This must be an <origin> or something like that.
-                      #f))
-                    patches))
-      (emit-warning package
-                    (_ "file names of patches should start with \
+(define (check-patch-file-names package)
+  "Emit a warning if the patches requires by PACKAGE are badly named or if the
+patch could not be found."
+  (guard (c ((message-condition? c)               ;raised by 'search-patch'
+             (emit-warning package (condition-message c)
+                           'patch-file-names)))
+    (let ((patches   (and=> (package-source package) origin-patches))
+          (name      (package-name package))
+          (full-name (package-full-name package)))
+      (when (and patches
+                 (any (match-lambda
+                        ((? string? patch)
+                         (let ((file (basename patch)))
+                           (not (or (eq? (string-contains file name) 0)
+                                    (eq? (string-contains file full-name)
+                                         0)))))
+                        (_
+                         ;; This must be an <origin> or something like that.
+                         #f))
+                      patches))
+        (emit-warning package
+                      (_ "file names of patches should start with \
 the package name")
-                    'patches))))
+                      'patch-file-names)))))
 
 (define (escape-quotes str)
   "Replace any quote character in STR by an escaped quote character."
@@ -434,6 +444,25 @@ descriptions maintained upstream."
              (append-map (cut maybe-expand-mirrors <> %mirrors)
                          uris))))))
 
+(define (check-derivation package)
+  "Emit a warning if we fail to compile PACKAGE to a derivation."
+  (catch #t
+    (lambda ()
+      (guard (c ((nix-protocol-error? c)
+                 (emit-warning package
+                               (format #f (_ "failed to create derivation: ~a")
+                                       (nix-protocol-error-message c))))
+                ((message-condition? c)
+                 (emit-warning package
+                               (format #f (_ "failed to create derivation: ~a")
+                                       (condition-message c)))))
+        (with-store store
+          (package-derivation store package))))
+    (lambda args
+      (emit-warning package
+                    (format #f (_ "failed to create derivation: ~s~%")
+                            args)))))
+
 
 
 ;;;
@@ -455,9 +484,9 @@ descriptions maintained upstream."
      (description "Identify inputs that should be native inputs")
      (check       check-inputs-should-be-native))
    (lint-checker
-     (name        'patch-filenames)
-     (description "Validate file names of patches")
-     (check       check-patches))
+     (name        'patch-file-names)
+     (description "Validate file names and availability of patches")
+     (check       check-patch-file-names))
    (lint-checker
      (name        'home-page)
      (description "Validate home-page URLs")
@@ -467,6 +496,10 @@ descriptions maintained upstream."
      (description "Validate source URLs")
      (check       check-source))
    (lint-checker
+     (name        'derivation)
+     (description "Report failure to compile a package to a derivation")
+     (check       check-derivation))
+   (lint-checker
      (name        'synopsis)
      (description "Validate package synopses")
      (check       check-synopsis-style))))
diff --git a/guix/scripts/refresh.scm b/guix/scripts/refresh.scm
index 04886499a2..28519d78e2 100644
--- a/guix/scripts/refresh.scm
+++ b/guix/scripts/refresh.scm
@@ -1,5 +1,5 @@
 ;;; GNU Guix --- Functional package management for GNU
-;;; Copyright © 2013, 2014 Ludovic Courtès <ludo@gnu.org>
+;;; Copyright © 2013, 2014, 2015 Ludovic Courtès <ludo@gnu.org>
 ;;; Copyright © 2013 Nikita Karetnikov <nikita@karetnikov.org>
 ;;; Copyright © 2014 Eric Bavier <bavier@member.fsf.org>
 ;;;
@@ -207,16 +207,13 @@ update would trigger a complete rebuild."
          (list-dependent? (assoc-ref opts 'list-dependent?))
          (key-download    (assoc-ref opts 'key-download))
          (packages
-          (match (concatenate
-                  (filter-map (match-lambda
-                               (('argument . value)
-                                (let ((p (find-packages-by-name value)))
-                                  (when (null? p)
-                                    (leave (_ "~a: no package by that name~%")
-                                           value))
-                                  p))
+          (match (filter-map (match-lambda
+                               (('argument . spec)
+                                ;; Take either the specified version or the
+                                ;; latest one.
+                                (specification->package spec))
                                (_ #f))
-                              opts))
+                             opts)
                  (()                          ; default to all packages
                   (let ((select? (match (assoc-ref opts 'select)
                                         ('core core-package?)
diff --git a/guix/scripts/system.scm b/guix/scripts/system.scm
index 1b64e6fb92..1838e89452 100644
--- a/guix/scripts/system.scm
+++ b/guix/scripts/system.scm
@@ -69,21 +69,7 @@
          (set-current-module %user-module)
          (primitive-load file))))
     (lambda args
-      (match args
-        (('system-error . _)
-         (let ((err (system-error-errno args)))
-           (leave (_ "failed to open operating system file '~a': ~a~%")
-                  file (strerror err))))
-        (('syntax-error proc message properties form . rest)
-         (let ((loc (source-properties->location properties)))
-           (format (current-error-port) (_ "~a: error: ~a~%")
-                   (location->string loc) message)
-           (exit 1)))
-        ((error args ...)
-         (report-error (_ "failed to load operating system file '~a':~%")
-                       file)
-         (apply display-error #f (current-error-port) args)
-         (exit 1))))))
+      (report-load-error file args))))
 
 
 ;;;
diff --git a/guix/svn-download.scm b/guix/svn-download.scm
index 92b03d13f3..d6853ca861 100644
--- a/guix/svn-download.scm
+++ b/guix/svn-download.scm
@@ -62,7 +62,7 @@ HASH-ALGO (a symbol).  Use NAME as the file name, or a generic name if #f."
         (svn-fetch '#$(svn-reference-url ref)
                    '#$(svn-reference-revision ref)
                    #$output
-                   #:svn-command (string-append #$svn "/bin/svn"))))
+                   #:svn-command (string-append #+svn "/bin/svn"))))
 
   (mlet %store-monad ((guile (package->derivation guile system)))
     (gexp->derivation (or name "svn-checkout") build
diff --git a/guix/ui.scm b/guix/ui.scm
index 67c65aa14d..5ca5afe457 100644
--- a/guix/ui.scm
+++ b/guix/ui.scm
@@ -47,6 +47,8 @@
             P_
             report-error
             leave
+            report-load-error
+            warn-about-load-error
             show-version-and-exit
             show-bug-report-information
             string->number*
@@ -130,6 +132,38 @@ messages."
     (report-error args ...)
     (exit 1)))
 
+(define (report-load-error file args)
+  "Report the failure to load FILE, a user-provided Scheme file, and exit.
+ARGS is the list of arguments received by the 'throw' handler."
+  (match args
+    (('system-error . _)
+     (let ((err (system-error-errno args)))
+       (leave (_ "failed to load '~a': ~a~%") file (strerror err))))
+    (('syntax-error proc message properties form . rest)
+     (let ((loc (source-properties->location properties)))
+       (format (current-error-port) (_ "~a: error: ~a~%")
+               (location->string loc) message)
+       (exit 1)))
+    ((error args ...)
+     (report-error (_ "failed to load '~a':~%") file)
+     (apply display-error #f (current-error-port) args)
+     (exit 1))))
+
+(define (warn-about-load-error file args)         ;FIXME: factorize with ↑
+  "Report the failure to load FILE, a user-provided Scheme file, without
+exiting.  ARGS is the list of arguments received by the 'throw' handler."
+  (match args
+    (('system-error . _)
+     (let ((err (system-error-errno args)))
+       (warning (_ "failed to load '~a': ~a~%") file (strerror err))))
+    (('syntax-error proc message properties form . rest)
+     (let ((loc (source-properties->location properties)))
+       (format (current-error-port) (_ "~a: warning: ~a~%")
+               (location->string loc) message)))
+    ((error args ...)
+     (warning (_ "failed to load '~a':~%") file)
+     (apply display-error #f (current-error-port) args))))
+
 (define (install-locale)
   "Install the current locale settings."
   (catch 'system-error