Hello, I've encountered a kind of bizarre error when trying to build GNU LilyPond regression tests on Cygwin 3.5.7-1 on Windows 11. For one and only one folder, `mv` fails with `mv: cannot move './out-test' to './out-test-baseline': Permission denied`. The distinguishing feature of the failing folder seems to be that it contains its own subfolder with a copy of all the regtest files, some of which have rather long names. When I remove this subfolder, the error goes away. The error also goes away if I execute the rename in a way that forces a physical move of the files.
Based on this, it appears to me that when an in-place rename is performed by `mv`, it calls into a Win32 API that enforces the 260 character MAX_PATH. I can see in the trace that the error is occurring within a Win32 call stack for resolving absolute path names, though the error code isn't specific enough to distinguish the precise reason for the failure. I tried enabling LongPathsEnabled in the registry, but I get the same `mv` error after doing so and rebooting. I reported this as a LilyPond bug with some further detail here https://gitlab.com/lilypond/lilypond/-/issues/6799, but the initial sentiment seems to be that this is an upstream issue. In some respect this doesn't seem like a specifically Cygwin issue, since I encountered the same error in the same spot on WSL2 if the build tree was on the Windows filesystem. But I'm guessing if anybody knows how to answer this, it's probably folks on this list. Any ideas what's going on here and how I might get it working? Is this a known type of issue? Is it a bug? If it's a bug, what is it a bug in? Right now, LilyPond's developer documentation basically just says not to bother trying to compile on Windows. It would be REALLY nice to change that, and this is the only blocking issue from recommending Cygwin as a viable compilation environment for LilyPond development. Thanks in advance for your help, Saul -- Problem reports: https://cygwin.com/problems.html FAQ: https://cygwin.com/faq/ Documentation: https://cygwin.com/docs.html Unsubscribe info: https://cygwin.com/ml/#unsubscribe-simple
