--- old/src/hotspot/cpu/ppc/globals_ppc.hpp	2020-02-03 17:41:35.000000000 -0500
+++ new/src/hotspot/cpu/ppc/globals_ppc.hpp	2020-02-03 17:41:34.000000000 -0500
@@ -74,6 +74,10 @@
 // 2x unrolled loop is shorter with more than 9 HeapWords.
 define_pd_global(intx, InitArrayShortSize, 9*BytesPerLong);
 
+// ObjectMonitor ref_count not implemented in C2 fast_lock() or
+// fast_unlock() so use a handshake for safety.
+define_pd_global(bool, HandshakeAfterDeflateIdleMonitors, true);
+
 // Platform dependent flag handling: flags only defined on this platform.
 #define ARCH_FLAGS(develop,      \
                    product,      \