From 48623f5be854e923b04ae83a1a882ff1cefdc742 Mon Sep 17 00:00:00 2001
From: Ricardo Wurmus <rekado@elephly.net>
Date: Thu, 31 Aug 2017 19:15:21 +0200
Subject: [PATCH] gnu: gzip: Use absolute name for gzip in gunzip.

* gnu/packages/compression.scm (gzip)[arguments]: Add build phase
"use-absolute-name-of-gzip".

Fixes <https://bugs.gnu.org/28158>.
---
 gnu/packages/compression.scm | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/gnu/packages/compression.scm b/gnu/packages/compression.scm
index 4e316e0b5a..cd9ed7cccf 100644
--- a/gnu/packages/compression.scm
+++ b/gnu/packages/compression.scm
@@ -4,7 +4,7 @@
 ;;; Copyright © 2014, 2015 Mark H Weaver <mhw@netris.org>
 ;;; Copyright © 2015 Taylan Ulrich Bayırlı/Kammer <taylanbayirli@gmail.com>
 ;;; Copyright © 2015, 2016 Eric Bavier <bavier@member.fsf.org>
-;;; Copyright © 2015, 2016 Ricardo Wurmus <rekado@elephly.net>
+;;; Copyright © 2015, 2016, 2017 Ricardo Wurmus <rekado@elephly.net>
 ;;; Copyright © 2015, 2017 Leo Famulari <leo@famulari.name>
 ;;; Copyright © 2015 Jeff Mickey <j@codemac.net>
 ;;; Copyright © 2015, 2016, 2017 Efraim Flashner <efraim@flashner.co.il>
@@ -202,7 +202,16 @@ adding and extracting files to/from a tar archive.")
    (synopsis "General file (de)compression (using lzw)")
    (arguments
     ;; FIXME: The test suite wants `less', and optionally Perl.
-    '(#:tests? #f))
+    '(#:tests? #f
+      #:phases
+      (modify-phases %standard-phases
+        (add-after 'unpack 'use-absolute-name-of-gzip
+          (lambda* (#:key outputs #:allow-other-keys)
+            (substitute* "gunzip.in"
+              (("exec gzip")
+               (string-append "exec " (assoc-ref outputs "out")
+                              "/bin/gzip")))
+            #t)))))
    (description
     "GNU Gzip provides data compression and decompression utilities; the
 typical extension is \".gz\".  Unlike the \"zip\" format, it compresses a single