cache_sync() copy Any/Union #519

Job	Run time
Linux centos 7	4m 16s
Linux fedora latest	4m 35s
Native Linux (WError)	5m 26s
Native Linux (libc++ debug)	5m 37s
Native Linux (c++17)	4m 54s
Cross mingw64 DLL	10m 33s
Cross mingw64 static	11m 26s
RTEMS5	15m 9s
Native Linux with clang	4m 32s
Native Linux with clang ubsan	4m 58s
Native Linux with libevent stable	4m 35s
Native Linux with 7.0.2	4m 56s
Native Linux with 3.15	3m 51s
Native Linux with 3.14	6m 48s
OSX	3m 14s
vs2019 DLL	8m 47s
vs2019 static	8m 2s
	1h 51m 39s

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