Fix esan compilation against glibc 2.26:

  /tmp/guix-build-clang-runtime-3.9.1.drv-0/compiler-rt-3.9.1.src/lib/esan/esan_sideline_linux.cpp: In static member function ‘static int __esan::SidelineThread::runSideline(void*)’:
  /tmp/guix-build-clang-runtime-3.9.1.drv-0/compiler-rt-3.9.1.src/lib/esan/esan_sideline_linux.cpp:73:22: error: aggregate ‘__esan::SidelineThread::runSideline(void*)::sigaltstack SigAltStack’ has incomplete type and cannot be defined

Patch from <https://github.com/google/sanitizers/issues/822>.

index d04f5909d..bc272dfe4 100644
--- a/lib/esan/esan_sideline_linux.cpp
+++ b/lib/esan/esan_sideline_linux.cpp
@@ -70,7 +70,7 @@ int SidelineThread::runSideline(void *Arg) {
 
   // Set up a signal handler on an alternate stack for safety.
   InternalScopedBuffer<char> StackMap(SigAltStackSize);
-  struct sigaltstack SigAltStack;
+  stack_t SigAltStack;
   SigAltStack.ss_sp = StackMap.data();
   SigAltStack.ss_size = SigAltStackSize;
   SigAltStack.ss_flags = 0;
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<tr><td><span title='2021-04-23 17:21:19 +0300'>2021-04-23</span></td><td><a href='/guix/commit/gnu/packages/cobol.scm?id=abee44d2c31b3be79be68806d5721bf3edfa77e2'>gnu: cobol: Add missing inputs.</a><span class='msg-avail'>...<span class='msg-tooltip'>Reported by Simon Sobisch &lt;simonsobisch@gnu.org&gt;.

* gnu/packages/cobol.scm (gnucobol)[inputs]: Add json-c, libxml2. Move
newcob ...
[native-inputs]: ... to here.
[arguments]: Add configure-flag to set json-c cflags.
</span></span></td><td>Efraim Flashner</td></tr>
<tr><td><span title='2021-04-23 17:10:14 +0300'>2021-04-23</span></td><td><a href='/guix/commit/gnu/packages/cobol.scm?id=7af92387cf537bcf0d597a0d875e411da4218834'>gnu: gnucobol: Update home-page.</a><span class='msg-avail'>...<span class='msg-tooltip'>Reported by Simon Sobisch &lt;simonsobisch@gnu.org&gt;.

* gnu/packages/cobol.scm (gnucobol)[home-page]: Use official home-page.
</span></span></td><td>Efraim Flashner</td></tr>
<tr><td><span title='2021-03-10 06:54:58 +0100'>2021-03-10</span></td><td><a href='/guix/commit/gnu/packages/cobol.scm?id=80739ea480a7db667b83b45e3a08be740449f689'>gnu: gnucobol: Update to 3.1.2 [security fixes].</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/cobol.scm (gnucobol): Update to 3.1.2.
[arguments]: Add 'set-TERM phase before 'check to set the TERM environment
variable for tests that expect it.
</span></span></td><td>Léo Le Bouter</td></tr>