cache_sync() copy Any/Union #794

Job	Run time
Linux centos 7	4m 29s
Linux fedora latest	4m 29s
Native Linux (WError)	4m 58s
Native Linux (libc++ debug)	5m 35s
Native Linux (c++17)	4m 43s
Cross mingw64 DLL	10m 19s
Cross mingw64 static	11m 32s
RTEMS5	14m 1s
Native Linux with clang	4m 30s
Native Linux with clang ubsan	4m 59s
Native Linux with libevent stable	4m 29s
Native Linux with 7.0.2	4m 45s
Native Linux with 3.15	3m 49s
Native Linux with 3.14	5m 56s
OSX	3m 6s
vs2019 DLL	8m 7s
vs2019 static	9m 43s
	1h 49m 30s

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