The Guile process taking the role of PID 1 during Guix builds does not reap
zombie processes, which makes them continue responding to "kill -0".

--- a/src/testsuite/stop-server.sh	2015-02-05 11:24:00.535908842 +0100
+++ b/src/testsuite/stop-server.sh	2015-02-05 11:25:00.264351349 +0100
@@ -1,6 +1,21 @@
 #!/bin/sh
 # ngIRCd Test Suite
 
+process_is_alive(){
+    ! process_is_dead "$1" && ! process_is_undead "$1"
+}
+
+process_is_dead(){
+    ! kill -0 "$1"
+}
+
+process_is_undead(){
+    case $(ps -p "$1" -o state=) in
+        (Z*) true ;;
+        (*) false ;;
+    esac
+}
+
 [ -z "$srcdir" ] && srcdir=`dirname $0`
 
 # read in functions
@@ -24,7 +40,7 @@
 
 # waiting ...
 for i in 1 2 3 4 5; do
-  kill -0 $pid > /dev/null 2>&1; r=$?
+  process_is_alive $pid > /dev/null 2>&1; r=$?
   if [ $r -ne 0 ]; then
     echo " ok".
     exit 0
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<div class='path'>path: <a href='/guix/log/?id=c88a870e9c13c54adafc69855df2d00ed200782f'>root</a>/<a href='/guix/log/tests?id=c88a870e9c13c54adafc69855df2d00ed200782f'>tests</a>/<a href='/guix/log/tests/elpa.scm?id=c88a870e9c13c54adafc69855df2d00ed200782f'>elpa.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/elpa.scm?id=c88a870e9c13c54adafc69855df2d00ed200782f&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2021-03-06 11:41:48 +0100'>2021-03-06</span></td><td><a href='/guix/commit/tests/elpa.scm?id=c05ceaf2b650d090cf39a048193505cb4e6bd257'>tests: do not hard code HTTP ports</a><span class='msg-avail'>...<span class='msg-tooltip'>Previously, test cases could fail if some process was listening
at a hard-coded port.  This patch eliminates most of these potential
failures, by automatically assigning an unbound port.  This should
allow for building multiple guix trees in parallel outside a build
container, though this is currently untested.

The test "home-page: Connection refused" in tests/lint.scm still
hardcodes port 9999, however.

* guix/tests/http.scm
  (http-server-can-listen?): remove now unused procedure.
  (%http-server-port): default to port 0, meaning the OS
  will automatically choose a port.
  (open-http-server-socket): remove the false statement claiming
  this procedure is exported and also return the allocated port
  number.
  (%local-url): raise an error if the port is obviously unbound.
  (call-with-http-server): set %http-server-port to the allocated
  port while the thunk is called.
* tests/derivations.scm: adjust test cases to use automatically
  assign a port.  As there is no risk of a port conflict now,
  do not make any tests conditional upon 'http-server-can-listen?'
  anymore.
* tests/elpa.scm: likewise.
* tests/lint.scm: likewise, and add a TODO comment about a port
  that is still hard-coded.
* tests/texlive.scm: likewise.

Signed-off-by: Ludovic Courtès &lt;ludo@gnu.org&gt;
</span></span></td><td>Maxime Devos</td></tr>
<tr><td><span title='2020-12-02 22:09:23 +0100'>2020-12-02</span></td><td><a href='/guix/commit/tests/elpa.scm?id=bea3b17739fc591b8cf6db1f8d28a6f6c9585577'>import: utils: 'recursive-import' accepts an optional version parameter.</a><span class='msg-avail'>...<span class='msg-tooltip'>This adds a key VERSION to 'recursive-import' and moves the parameter REPO to
a key. This also changes all the places that rely on 'recursive-import'.

* guix/import/utils.scm (recursive-import): Add the VERSION key. Make REPO a
  key.
  (package-&gt;definition): Add optional 'append-version?'.
* guix/scripts/import/crate.scm (guix-import-crate): Add the VERSION key.
* guix/import/crate.scm (crate-&gt;guix-package): Add the VERSION key.
  (crate-recursive-import): Pass VERSION to recursive-import, remove now
  unnecessary code.
* guix/import/cran.scm (cran-&gt;guix-package, cran-recursive-import): Change the
  REPO parameter to a key.
* guix/import/elpa.scm (elpa-&gt;guix-package, elpa-recursive-import): Likewise.
* guix/import/gem.scm (gem-&gt;guix-package, recursive-import): Likewise.
* guix/import/opam.scm (opam-recurive-import): Likewise.
* guix/import/pypi.scm (pypi-recursive-import): Likewise.
* guix/import/stackage.scm (stackage-recursive-import): Likewise.
* guix/scripts/import/cran.scm (guix-import-cran): Likewise.
* guix/scripts/import/elpa.scm (guix-import-elpa): Likewise.
* tests/elpa.scm (eval-test-with-elpa): Likewise.
* tests/import-utils.scm (recursive-import): Likewise.

Co-authored-by: Hartmut Goebel &lt;h.goebel@crazy-compilers.com&gt;
</span></span></td><td>Martin Becze</td></tr>