See https://groups.google.com/forum/#!topic/minisat/FCocZsC8oMQ
This seems to only be a problem with newer versions of g++, and
upstream development seems to have stopped in 2013.

diff -rupN minisat-2.2.0/core/SolverTypes.h minisat-2.2.0.patched/core/SolverTypes.h
--- a/minisat/core/SolverTypes.h	2010-07-10 17:07:36.000000000 +0100
+++ b/minisat/core/SolverTypes.h	2014-03-29 11:57:49.000000000 +0000
@@ -47,7 +47,7 @@ struct Lit {
     int     x;

     // Use this as a constructor:
-    friend Lit mkLit(Var var, bool sign = false);
+    //friend Lit mkLit(Var var, bool sign = false);

     bool operator == (Lit p) const { return x == p.x; }
     bool operator != (Lit p) const { return x != p.x; }
@@ -55,7 +55,7 @@ struct Lit {
 };


-inline  Lit  mkLit     (Var var, bool sign) { Lit p; p.x = var + var + (int)sign; return p; }
+inline  Lit  mkLit     (Var var, bool sign = false) { Lit p; p.x = var + var + (int)sign; return p; }
 inline  Lit  operator ~(Lit p)              { Lit q; q.x = p.x ^ 1; return q; }
 inline  Lit  operator ^(Lit p, bool b)      { Lit q; q.x = p.x ^ (unsigned int)b; return q; }
 inline  bool sign      (Lit p)              { return p.x & 1; }
guix/log/tests/gnu-maintenance.scm'>log</a><a href='/guix/tree/tests/gnu-maintenance.scm?id=9e3ee89786e6f824a8cc7f490acf7809e69df325'>tree</a><a href='/guix/commit/tests/gnu-maintenance.scm?id=9e3ee89786e6f824a8cc7f490acf7809e69df325'>commit</a><a href='/guix/diff/tests/gnu-maintenance.scm?id=9e3ee89786e6f824a8cc7f490acf7809e69df325'>diff</a></td><td class='form'><form class='right' method='get' action='/guix/log/tests/gnu-maintenance.scm'>
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<div class='path'>path: <a href='/guix/log/?id=9e3ee89786e6f824a8cc7f490acf7809e69df325'>root</a>/<a href='/guix/log/tests?id=9e3ee89786e6f824a8cc7f490acf7809e69df325'>tests</a>/<a href='/guix/log/tests/gnu-maintenance.scm?id=9e3ee89786e6f824a8cc7f490acf7809e69df325'>gnu-maintenance.scm</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/gnu-maintenance.scm?id=9e3ee89786e6f824a8cc7f490acf7809e69df325&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2021-05-28 23:04:44 +0200'>2021-05-28</span></td><td><a href='/guix/commit/tests/gnu-maintenance.scm?id=d7c356edb9719f1e236ee926c0288f914076481a'>gnu-maintenance: 'release-file?' accepts 'v' prefix as in "PKG-v1.2.tgz".</a><span class='msg-avail'>...<span class='msg-tooltip'>* guix/gnu-maintenance.scm (%tarball-rx, %package-name-rx): Accept 'v'
and 'V' prefixes.  Accept ".tgz" extension.
* tests/gnu-maintenance.scm ("release-file?"): Add test.
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2021-04-05 12:03:09 +0200'>2021-04-05</span></td><td><a href='/guix/commit/tests/gnu-maintenance.scm?id=ceeea60bbc1e2be6a86cef208fcd80eb61c92934'>gnu-maintenance: Recognize more source tarball naming schemes.</a><span class='msg-avail'>...<span class='msg-tooltip'>* guix/gnu-maintenance.scm (%package-name-rx): Add ".src" and ".orig"
suffixes.
* tests/gnu-maintenance.scm ("release-file?"): Add mpg321 and bvi
examples.
("tarball-&gt;version"): New test.
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2021-03-29 23:33:40 +0200'>2021-03-29</span></td><td><a href='/guix/commit/tests/gnu-maintenance.scm?id=1575da60628cf2594cd7b1ab0812ec4c50ac5092'>gnu-maintenance: Recognize "-source" tarball suffix.</a><span class='msg-avail'>...<span class='msg-tooltip'>Fixes &lt;https://bugs.gnu.org/47398&gt;.
Reported by Léo Le Bouter &lt;lle-bout@zaclys.net&gt;.

* guix/gnu-maintenance.scm (%tarball-rx): Add "-[Ss]ource" suffix.
* tests/gnu-maintenance.scm ("release-file?"): Add exiv2 example.
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2021-03-20 22:29:14 +0100'>2021-03-20</span></td><td><a href='/guix/commit/tests/gnu-maintenance.scm?id=1710e8cb59e2ef6f1e0eb19235b6a4f1b8158bc4'>gnu-maintenance: Accept underscores as package/version separators.</a><span class='msg-avail'>...<span class='msg-tooltip'>Fixes &lt;https://bugs.gnu.org/47256&gt;.
Reported by Léo Le Bouter &lt;lle-bout@zaclys.net&gt;.

* guix/gnu-maintenance.scm (%tarball-rx, %package-name-rx): Accept
underscore as the package/version separator in tarball names.
* tests/gnu-maintenance.scm ("release-file?"): Add "mediainfo" test.
</span></span></td><td>Ludovic Courtès</td></tr>