see https://lists.pld-linux.org/mailman/pipermail/pld-devel-en/2021-November/026415.html
--- /dev/null
+--- jdk8u-jdk8u312-ga/common/autoconf/boot-jdk.m4.orig 2021-09-14 01:27:07.000000000 +0200
++++ jdk8u-jdk8u312-ga/common/autoconf/boot-jdk.m4 2021-11-24 21:50:44.335912643 +0100
+@@ -51,7 +51,7 @@
+ BOOT_JDK_FOUND=no
+ else
+ # Oh, this is looking good! We probably have found a proper JDK. Is it the correct version?
+- BOOT_JDK_VERSION=`"$BOOT_JDK/bin/java" -version 2>&1 | head -n 1`
++ BOOT_JDK_VERSION=`"$BOOT_JDK/bin/java" -version 2>&1 | grep -v _JAVA_OPTIONS | head -n 1`
+
+ # Extra M4 quote needed to protect [] in grep expression.
+ [FOUND_VERSION_78=`echo $BOOT_JDK_VERSION | grep '\"1\.[78]\.'`]
Patch11: aarch32.patch
Patch12: atomic.patch
Patch13: hotspot-disable-werror.patch
+Patch14: ignore-java-options.patch
URL: http://openjdk.java.net/
BuildRequires: /usr/bin/jar
BuildRequires: alsa-lib-devel
%patch12 -p1
%endif
%patch13 -p1
+%patch14 -p1
%build
# Make sure we have /proc mounted - otherwise idlc will fail later.
unset JAVA_HOME
unset CLASSPATH
+# force locking irrespective of cpu count determined based on /proc and /sys contents
+# https://lists.pld-linux.org/mailman/pipermail/pld-devel-en/2021-November/026415.html
+export _JAVA_OPTIONS=-XX:+AssumeMP
+
mkdir -p build-bin
export PATH="$(pwd)/build-bin:$PATH"