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;
-scripts'>koszko-scripts</option>
</select> <input type='submit' value='switch'/></form></td></tr>
<tr><td class='sub'>Wojtek's customized Guix</td><td class='sub right'></td></tr></table>
<table class='tabs'><tr><td>
<a href='/guix/about/'>about</a><a href='/guix/'>summary</a><a href='/guix/refs/?id=0ece738474b82082a1f2a2cd2ae2bc31d99de9a4'>refs</a><a class='active' href='/guix/log/manifest.scm?showmsg=1'>log</a><a href='/guix/tree/manifest.scm?id=0ece738474b82082a1f2a2cd2ae2bc31d99de9a4'>tree</a><a href='/guix/commit/manifest.scm?id=0ece738474b82082a1f2a2cd2ae2bc31d99de9a4'>commit</a><a href='/guix/diff/manifest.scm?id=0ece738474b82082a1f2a2cd2ae2bc31d99de9a4'>diff</a></td><td class='form'><form class='right' method='get' action='/guix/log/manifest.scm'>
<input type='hidden' name='id' value='0ece738474b82082a1f2a2cd2ae2bc31d99de9a4'/><input type='hidden' name='showmsg' value='1'/><select name='qt'>
<option value='grep'>log msg</option>
<option value='author'>author</option>
<option value='committer'>committer</option>
<option value='range'>range</option>
</select>
<input class='txt' type='search' size='10' name='q' value=''/>
<input type='submit' value='search'/>
</form>
</td></tr></table>
<div class='path'>path: <a href='/guix/log/?id=0ece738474b82082a1f2a2cd2ae2bc31d99de9a4&amp;showmsg=1'>root</a>/<a href='/guix/log/manifest.scm?id=0ece738474b82082a1f2a2cd2ae2bc31d99de9a4&amp;showmsg=1'>manifest.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/manifest.scm?id=0ece738474b82082a1f2a2cd2ae2bc31d99de9a4'>Collapse</a>)</th><th class='left'>Author</th></tr>
<tr class='logheader'><td><span title='2024-06-24 08:51:43 -0400'>2024-06-24</span></td><td class='logsubject'><a href='/guix/commit/manifest.scm?id=7f194852a46edfe47537d11bc39fb1dd20e18b37'>manifest: Streamline; add packages useful for patch review/submission.</a></td><td>Maxim Cournoyer</td></tr>
<tr class='nohover-highlight'><td/><td colspan='3' class='logmsg'>
* manifest.scm: Fix alternate command line invocation (which would not
consider 'manifest.scm').  Use specifications instead of packages.  Remove
perl (now in the guix package's native inputs).  Add b4, git, git:send-email,
mumi, nss-certs, openssl and patman to the manifest.

Change-Id: I49d92dda059856ce217cea9054a466a1754dcf94
Signed-off-by: Maxim Cournoyer &lt;maxim.cournoyer@gmail.com&gt;


</td></tr>
<tr class='logheader'><td><span title='2024-04-02 23:28:58 +0200'>2024-04-02</span></td><td class='logsubject'><a href='/guix/commit/manifest.scm?id=049273bb8c1ea3d6402db646312acdc4abf4678a'>maint: Add perl to the manifest.</a></td><td>Janneke Nieuwenhuizen</td></tr>
<tr class='nohover-highlight'><td/><td colspan='3' class='logmsg'>
* manifest.scm: Add perl.

Change-Id: Ie70cea1eb4d62f2a649292209391a92abdae2288


</td></tr>
<tr class='logheader'><td><span title='2024-01-31 09:07:25 +0100'>2024-01-31</span></td><td class='logsubject'><a href='/guix/commit/manifest.scm?id=66dd088d3c3404f5cbe2d4d4c5e8f93d184703b0'>maint: Add gnupg to the manifest.</a></td><td>Ludovic Courtès</td></tr>
<tr class='nohover-highlight'><td/><td colspan='3' class='logmsg'>
* manifest.scm: Add gnupg.

Change-Id: Id5e90f87e5c3a07aa3e49afa97cc0b6d3ce71b41


</td></tr>
<tr class='logheader'><td><span title='2023-09-18 22:12:39 +0200'>2023-09-18</span></td><td class='logsubject'><a href='/guix/commit/manifest.scm?id=7bf12820f61179900f9d1f753acf91fd33724976'>maint: Support `guix shell' in Guix's git archive with manifest.scm.</a></td><td>Janneke Nieuwenhuizen</td></tr>
<tr class='nohover-highlight'><td/><td colspan='3' class='logmsg'>
* manifest.scm: New file.
* Makefile.am (EXTRA_DIST): Add it.
* doc/contributing.texi (Building from Git): Mention using it.


</td></tr>