Reported by Lubomir Rintel <lkundrak@v3.sk> in
<https://lists.gnu.org/archive/html/bug-gettext/2022-06/msg00022.html>.
* gettext-runtime/po/Makefile.in.in (.NOTPARALLEL): Add this special target.
# Tell versions [3.59,3.63) of GNU make not to export all variables.
# Otherwise a system limit (for SysV at least) may be exceeded.
.NOEXPORT:
+
+# This Makefile contains rules which don't work with parallel make,
+# namely dist2.
+# See <https://lists.gnu.org/archive/html/bug-gettext/2022-06/msg00022.html>.
+# So, turn off parallel execution in this Makefile.
+.NOTPARALLEL: