On Thu, Feb 27, 2014 at 1:37 PM, Manuel Klimek <[email protected]> wrote:
> On Wed, Feb 12, 2014 at 11:22 PM, Douglas Gregor <[email protected]>wrote: > >> >> On Feb 12, 2014, at 2:21 PM, Rafael Ávila de Espíndola < >> [email protected]> wrote: >> >> > >> > >> > ================ >> > Comment at: include/clang/Basic/FileManager.h:122 >> > @@ -121,2 +121,3 @@ >> > class FileManager : public RefCountedBase<FileManager> { >> > + IntrusiveRefCntPtr<AbstractFileSystem> FS; >> > FileSystemOptions FileSystemOpts; >> > ---------------- >> > Why is the reference count necessary? Given its nature I would expect >> the FS to outlive the file manger, in which case the FileManager could have >> just a pointer to the FileSystem. >> >> >> The FS is likely to get shared among a number of FileManagers in >> different compiler instances within a thread. Yes, we could try to >> establish and maintain relationships among these, but it’s simpler and >> costs us effectively nothing to make this ref-counted. >> > > Just to follow up: > I found one more argument against making this ref-counted: > The constructor of FileManager that uses the default "real" file system is > now actively thread hostile (you cannot create a FileManager per thread > without locking). I think that's rather unexpected. > And even worse, because RealFileSystem is an implementation detail, and getRealFileSystem returns a ref counted pointer by value, I cannot see any way to get me a RealFileSystem without locking. Cheers, /Manuel
_______________________________________________ cfe-commits mailing list [email protected] http://lists.cs.uiuc.edu/mailman/listinfo/cfe-commits
