Fix a string comparison in C++ 11.

Taken from Debian:
https://sources.debian.org/src/dbus-c++/0.9.0-8.1/debian/patches/06_fix_gcc-7_ftbfs.patch/

--- a/src/pipe.cpp
+++ b/src/pipe.cpp
@@ -83,5 +83,5 @@ ssize_t Pipe::read(void *buffer, unsigne
 void Pipe::signal()
 {
   // TODO: ignoring return of read/write generates warning; maybe relevant for eventloop work...
-  ::write(_fd_write, '\0', 1);
+  ::write(_fd_write, "\0", 1);
 }
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<tr><td><span title='2021-12-13 17:48:25 +0100'>2021-12-13</span></td><td><a href='/guix/commit/gnu/packages/idris.scm?id=8394619baceb118df92e355377fd543bb1aa501a'>gnu: Simplify package inputs.</a><span class='msg-avail'>...<span class='msg-tooltip'>This commit was obtained by running:

  ./pre-inst-env guix style

without any additional argument.
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2021-10-08 09:13:53 +0200'>2021-10-08</span></td><td><a href='/guix/commit/gnu/packages/idris.scm?id=ed044023d7ed8cfe113f4d6e1a6af17a09f49795'>gnu: idris: Fix build.</a><span class='msg-avail'>...<span class='msg-tooltip'>Backport some commits from upstream.

* gnu/packages/patches/idris-build-with-haskeline-0.8.patch:
* gnu/packages/patches/idris-build-with-megaparsec-9.patch: New patches
* gnu/local.mk (dist_patch_DATA): Add them.
* gnu/packages/idris.scm (idris): Use them.

Signed-off-by: Lars-Dominik Braun &lt;lars@6xq.net&gt;
</span></span></td><td>Xinglu Chen</td></tr>
<tr><td><span title='2021-10-08 09:13:52 +0200'>2021-10-08</span></td><td><a href='/guix/commit/gnu/packages/idris.scm?id=b97f549b14402421fcfb360ddd4cff7de93b9af0'>gnu: Update Haskell ecosystem.</a><span class='msg-avail'>...<span class='msg-tooltip'>Bump packages’ versions to the lastest Stackage or Hackage
release. Since packages are interdependent, do so in a single commit.

525 packages have been updated.

These packages have been removed, because they fail to build, have no
newer version available and no dependencies:

corrode
ghc-easytest
ghc-edisonapi
ghc-edisoncore
ghc-pandoc-types
ghc-regex-tdfa-text

These have been removed, because they are no longer required:

ghc-happy-1.19.9
ghc-prettyprinter-1.6
ghc-protolude-0.3

ghc-pandoc-citeproc and pandoc-citeproc have been removed, because pandoc
does not use them any more.

Co-authored-by: Xinglu Chen &lt;public@yoctocell.xyz&gt;
</span></span></td><td>Lars-Dominik Braun</td></tr>