This patch fixes a bug and related test failure on platforms where 'char'
is unsigned.

Taken from upstream:
https://github.com/open-source-parsers/jsoncpp/commit/f11611c8785082ead760494cba06196f14a06dcb

diff --git a/src/lib_json/json_writer.cpp b/src/lib_json/json_writer.cpp
index 8e06cca2..56195dc1 100644
--- a/src/lib_json/json_writer.cpp
+++ b/src/lib_json/json_writer.cpp
@@ -178,8 +178,9 @@ static bool isAnyCharRequiredQuoting(char const* s, size_t n) {
 
   char const* const end = s + n;
   for (char const* cur = s; cur < end; ++cur) {
-    if (*cur == '\\' || *cur == '\"' || *cur < ' ' ||
-        static_cast<unsigned char>(*cur) < 0x80)
+    if (*cur == '\\' || *cur == '\"' ||
+        static_cast<unsigned char>(*cur) < ' ' ||
+        static_cast<unsigned char>(*cur) >= 0x80)
       return true;
   }
   return false;
ption>
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<div class='path'>path: <a href='/guix/log/?id=b6d5a7f5836739dab884b49a64ca354794dd845f'>root</a>/<a href='/guix/log/po?id=b6d5a7f5836739dab884b49a64ca354794dd845f'>po</a>/<a href='/guix/log/po/doc?id=b6d5a7f5836739dab884b49a64ca354794dd845f'>doc</a>/<a href='/guix/log/po/doc/guix-manual.pt_BR.po?id=b6d5a7f5836739dab884b49a64ca354794dd845f'>guix-manual.pt_BR.po</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/po/doc/guix-manual.pt_BR.po?id=b6d5a7f5836739dab884b49a64ca354794dd845f&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2024-09-02 00:46:31 +0200'>2024-09-02</span></td><td><a href='/guix/commit/po/doc/guix-manual.pt_BR.po?id=dcc84e668d70558d7d48e340fe77a6cd5003e360'>nls: Update translations.</a><span class='msg-avail'>...<span class='msg-tooltip'>Change-Id: Icdee15b452c38ca885a8f202f68621916de01c03
</span></span></td><td>Florian Pelz</td></tr>
<tr><td><span title='2024-06-03 00:27:12 +0200'>2024-06-03</span></td><td><a href='/guix/commit/po/doc/guix-manual.pt_BR.po?id=834a4195241806784d4b321b95f06d85f458ce18'>nls: Update translations.</a><span class='msg-avail'>...<span class='msg-tooltip'>* po/doc/guix-cookbook.sv.po: New file.
* po/doc/local.mk: Add 'sv' cookbook.
* po/doc/po4a.cfg (po4a_langs): Add 'sv'.
* doc/local.mk: Add 'sv' cookbook.
* doc/htmlxref.cnf: Update URLs for cookbook.
* doc/build.scm (%cookbook-languages): Add 'sv'.
* doc/guix-cookbook.texi (Top): Mention 'sv' cookbook.

Change-Id: Ibfeb7254f583f1c8827e8c2756bbb02880bcba46
</span></span></td><td>Florian Pelz</td></tr>
<tr><td><span title='2024-04-01 14:09:20 +0200'>2024-04-01</span></td><td><a href='/guix/commit/po/doc/guix-manual.pt_BR.po?id=fa98837b1d9586b9ca7bf77dae22c3bde0fc59b5'>nls: Update translations.</a><span class='msg-avail'>...<span class='msg-tooltip'>* po/guix/ar.po: New file.
* po/guix/LINGUAS: Add 'ar'.
* po/doc/guix-cookbook.pt_BR.po: New file.
* po/doc/local.mk: Add 'pt_BR' cookbook.
* doc/local.mk: Add 'pt_BR' cookbook.
* doc/htmlxref.cnf: Update URLs for cookbook.
* doc/build.scm (%cookbook-languages): Add 'ko', 'pt_BR'.
* doc/guix-cookbook.texi (Top): Mention 'ko', 'pt_BR' cookbook.

Change-Id: Id1846ca100263b3fc1fa2ed52654c670270ee809
</span></span></td><td>Florian Pelz</td></tr>
<tr><td><span title='2023-10-05 23:14:54 +0200'>2023-10-05</span></td><td><a href='/guix/commit/po/doc/guix-manual.pt_BR.po?id=3d4d7fec05a8bdb0764a37515bb7c739b1094ab5'>doc: Fix channel name typo.</a><span class='msg-avail'>...<span class='msg-tooltip'>When the manual has "variant-personal-packages", it actually refers to the
channel "variant-packages", as it is named so elsewhere.

To correct this, I ran the command

    grep -r -l variant-personal-packages | xargs \
    sed -i 's/variang-personal-packages/variant-packages/g'

* doc/guix.texi (Specifying Additional Channels): Fix channel name typo.
* po/doc/guix-manual.de.po: Fix channel name typo.
* po/doc/guix-manual.es.po: Fix channel name typo.
* po/doc/guix-manual.fr.po: Fix channel name typo.
* po/doc/guix-manual.pt_BR.po: Fix channel name typo.
* po/doc/guix-manual.ru.po: Fix channel name typo.
* po/doc/guix-manual.zh_CN.po: Fix channel name typo.

Signed-off-by: Nikolaos Chatzikonstantinou &lt;nchatz314@gmail.com&gt;
Signed-off-by: Ludovic Courtès &lt;ludo@gnu.org&gt;
</span></span></td><td>Nikolaos Chatzikonstantinou</td></tr>
<tr><td><span title='2023-08-31 21:36:03 +0200'>2023-08-31</span></td><td><a href='/guix/commit/po/doc/guix-manual.pt_BR.po?id=57ab9536db20f98a36aeb25972137fbd752686cc'>nls: Update translations.</a></td><td>Florian Pelz</td></tr>
<tr><td><span title='2023-06-30 14:26:07 +0200'>2023-06-30</span></td><td><a href='/guix/commit/po/doc/guix-manual.pt_BR.po?id=8af22b493199a17f46351c2f3d9f6ee759e48564'>nls: Update translations.</a><span class='msg-avail'>...<span class='msg-tooltip'>* po/packages/ja.po: New file.
* po/packages/LINGUAS: Add it.
</span></span></td><td>Florian Pelz</td></tr>
<tr><td><span title='2023-05-31 17:23:21 +0200'>2023-05-31</span></td><td><a href='/guix/commit/po/doc/guix-manual.pt_BR.po?id=8e9e6a6482f3ba98d1cdcad344ee488e8751fee7'>nls: Update translations.</a><span class='msg-avail'>...<span class='msg-tooltip'>* doc/guix-cookbook.texi (Top): Mention Slovak.
</span></span></td><td>Florian Pelz</td></tr>
<tr><td><span title='2023-03-07 21:14:57 +0100'>2023-03-07</span></td><td><a href='/guix/commit/po/doc/guix-manual.pt_BR.po?id=d333958763b0840c4cd895601b079b68358a6a46'>nls: Update translations.</a></td><td>Julien Lepiller</td></tr>