tags 878462 + patch fixed-upstream thanks This issue is fixed upstream since release 2.48.4 (commit 4473822b5aa6de3e849ca6c958b365a71edbca4f fixed it).
Attached is a patch that fixes the FTBFS.
Index: unison-2.48.3/system/system_generic.ml =================================================================== --- unison-2.48.3.orig/system/system_generic.ml +++ unison-2.48.3/system/system_generic.ml @@ -57,7 +57,7 @@ let opendir f = let readdir = Unix.readdir let closedir = Unix.closedir let readlink = Unix.readlink -let symlink = Unix.symlink +let symlink s1 s2 = Unix.symlink s1 s2 let chdir = Sys.chdir let getcwd = Sys.getcwd