Do not assume the SDL_image and SLD_mixer libraries are installed at the same
prefix reported by sdl-config, but instead get flags from the pkg-config files
installed with these libraries.

--- a/SConscript	2011-12-24 15:46:47.000000000 -0600
+++ b/SConscript	2014-06-12 21:20:45.702668330 -0500
@@ -199,7 +199,13 @@
                 self.fatal_error += "  * library 'png' not found\n"
 
     def configure_sdl(self):
-        if self.conf.CheckMyProgram('sdl-config'):
+        if self.conf.CheckMyProgram('pkg-config'):
+            self.conf.env.ParseConfig("pkg-config --cflags --libs sdl")
+            for sdllib in ['image', 'mixer']:
+                self.conf.env.ParseConfig("pkg-config --cflags --libs SDL_%s" % sdllib)
+                if not self.conf.CheckSDLLib(sdllib):
+                    self.fatal_error += "  * SDL library '%s' not found\n" % sdllib
+        elif self.conf.CheckMyProgram('sdl-config'):
             self.conf.env.ParseConfig("sdl-config  --cflags --libs | sed 's/-I/-isystem/g'")
             for sdllib in ['image', 'mixer']:
                 if not self.conf.CheckSDLLib(sdllib):
10254a45ba'>refs</a><a class='active' href='/guix/log/tests/dsa.key'>log</a><a href='/guix/tree/tests/dsa.key?id=b31730fec6c8522ffa3039eb65828c10254a45ba'>tree</a><a href='/guix/commit/tests/dsa.key?id=b31730fec6c8522ffa3039eb65828c10254a45ba'>commit</a><a href='/guix/diff/tests/dsa.key?id=b31730fec6c8522ffa3039eb65828c10254a45ba'>diff</a></td><td class='form'><form class='right' method='get' action='/guix/log/tests/dsa.key'>
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<div class='path'>path: <a href='/guix/log/?id=b31730fec6c8522ffa3039eb65828c10254a45ba'>root</a>/<a href='/guix/log/tests?id=b31730fec6c8522ffa3039eb65828c10254a45ba'>tests</a>/<a href='/guix/log/tests/dsa.key?id=b31730fec6c8522ffa3039eb65828c10254a45ba'>dsa.key</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/guix/log/tests/dsa.key?id=b31730fec6c8522ffa3039eb65828c10254a45ba&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2020-05-04 09:56:12 +0200'>2020-05-04</span></td><td><a href='/guix/commit/tests/dsa.key?id=43408e304ffb1149f35cb539b40d673d567c9116'>Add (guix openpgp).</a><span class='msg-avail'>...<span class='msg-tooltip'>* guix/openpgp.scm, tests/openpgp.scm, tests/civodul.key,
tests/dsa.key, tests/ed25519.key, tests/rsa.key,
tests/ed25519.sec: New files.
* Makefile.am (MODULES): Add guix/openpgp.scm.
(SCM_TESTS): Add tests/openpgp.scm.
(EXTRA_DIST): Add tests/*.key and tests/ed25519.sec.
</span></span></td><td>Ludovic Courtès</td></tr>
i srfi-26) from (host-)
imported modules.
</span></span></td><td>Tobias Geerinckx-Rice</td></tr>
<tr><td><span title='2019-06-11 21:05:32 +0200'>2019-06-11</span></td><td><a href='/guix/commit/gnu/services/nix.scm?id=2be6b5e2eea9ac084cc22281f64f7a089e46cdae'>services: Add SRFI-26 to Nix activation gexp.</a><span class='msg-avail'>...<span class='msg-tooltip'>Fix the following fatal error on ‘guix system reconfigure’:

Backtrace:
          18 (primitive-load "/home/nckx/.config/guix/current/bin/guix")
In guix/ui.scm:
  1620:12 17 (run-guix-command _ . _)
In ice-9/boot-9.scm:
    829:9 16 (catch _ _ #&lt;procedure 7a7caa2d4c80 at guix/ui.scm:587:2 (key c)&gt; _)
    829:9 15 (catch _ _ #&lt;procedure 7a7caa2d4c98 at guix/ui.scm:710:6 (key proc format-string format-args . …&gt; …)
In guix/scripts/system.scm:
   1325:8 14 (_)
In guix/status.scm:
    768:4 13 (call-with-status-report _ _)
In guix/scripts/system.scm:
   1181:4 12 (process-action _ _ _)
In guix/store.scm:
   623:10 11 (call-with-store _)
  1800:24 10 (run-with-store _ _ #:guile-for-build _ #:system _ #:target _)
In guix/scripts/system.scm:
   920:13  9 (_ _)
    409:8  8 (_ _)
In unknown file:
           7 (primitive-load "/gnu/store/dha7j9gcz3vgb8cy7vfvvaswwsywrrzj-activate")
In ice-9/boot-9.scm:
   260:13  6 (for-each #&lt;procedure primitive-load (_)&gt; _)
In unknown file:
           5 (primitive-load "/gnu/store/ql1xjxrssxm51z2bn2v6l3mlrncij84h-activate-service")
In ice-9/eval.scm:
    619:8  4 (_ #f)
   196:35  3 (_ #f)
   196:27  2 (_ #f)
   223:20  1 (proc #&lt;directory (guile-user) 1fa4140&gt;)
In unknown file:
           0 (%resolve-variable (7 . cut) #&lt;directory (guile-user) 1fa4140&gt;)

ERROR: In procedure %resolve-variable:
error: cut: unbound variable

Reported-by: Alex McGrath on #guix.

* gnu/services/nix.scm (nix-activation): Import and use (srfi srfi-26).
</span></span></td><td>Tobias Geerinckx-Rice</td></tr>
<tr><td><span title='2019-06-10 09:15:45 +0300'>2019-06-10</span></td><td><a href='/guix/commit/gnu/services/nix.scm?id=47b9614b3110307093382363c0ba70d31f32ef59'>services: Add 'nix-service-type'.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/services/nix.scm: New file.
* gnu/local.mk: Add this.
* doc/guix.texi (Miscellaneous Services): Document this.
</span></span></td><td>Oleg Pykhalov</td></tr>