up.txt CACN.ini GameGuard/CACN.ini c:\rc\rsync -rltzpP --chmod=auog+rwx --files-from=/cygdrive/c/rc/up.txt --partial-dir=/cygdrive/d/temp --delay-updates test@222.218.45.7::test/泡泡堂/ /cygdrive/d/泡泡堂/ C:\rc>c:\rc\rsync -rltzpP --chmod=auog+rwx --files-from=/cygdrive/c/rc/up.tx t --partial-dir=/cygdrive/d/temp --delay-updates test@222.218.45.7::test/泡泡堂 / /cygdrive/d/泡泡堂/ receiving file list ... 3 files to consider CACN.ini 402 100% 392.58kB/s 0:00:00 (xfer#1, to-check=2/3) GameGuard/ GameGuard/CACN.ini 416 100% 2.88kB/s 0:00:00 (xfer#2, to-check=0/3) rsync: rename failed for "/cygdrive/d/泡泡堂/GameGuard/CACN.ini" (from /cygdrive /d/temp/CACN.ini): No such file or directory (2) sent 67 bytes received 1011 bytes 196.00 bytes/sec total size is 818 speedup is 0.76 rsync error: some files/attrs were not transferred (see previous errors) (code 2 3) at main.c(1506) [generator=3.0.4]
What makes you think this is a bug in rsync? To me it looks more likely to be caused by Windows and/or Cygwin mishandling the special characters in the path.
There is no evidence that this is a bug in rsync.