On Tue, Jan 25, 2022 at 7:32 PM Peter Maydell <peter.mayd...@linaro.org> wrote: > > On Tue, 25 Jan 2022 at 04:14, Akihiko Odaki <akihiko.od...@gmail.com> wrote: > > I'm neutral about the decision. I think QEMU should avoid using > > Objective-C code except for interactions with Apple's APIs, and .c is > > superior in terms of that as it would prevent accidental introduction > > of Objective-C code. On the other hand, naming them .m will allow the > > introduction of Automatic Reference Counting to manage dispatch queue > > objects. In fact, I have found a few memory leaks in vmnet in the last > > review and ui/cocoa.m has a suspicious construction of the object > > management (Particularly it has asynchronous dispatches wrapped with > > NSAutoreleasePool, which does not make sense). > > I think those are probably my fault -- in commit 6e657e64cd (in 2013) > we added NSAutoReleasePools to fix leaks that happened because > we were calling into Cocoa APIs from threads other than the UI > thread that didn't have their own automatically created autorelease > pool. Much later in commit 5588840ff778 (in 2019) we put in the > dispatch_async stuff because newer macOS was stricter about > requiring Cocoa API calls to be only on the UI thread. So > I think that means the requirement for the autorelease pools > has now gone away in those functions and we could simply delete > them -- does that sound right? (I freely admit that I'm not a macOS > expert -- I just look stuff up in the documentation; historically > we haven't really had many expert macOS people around to work on > cocoa.m...)
Removing them would be an improvement. Enabling ARC is a long-term solution and would allow clang to analyze object management code and answer such a question semi-automatically. Regards, Akihiko Odaki > > On the subject of cocoa.m, while we have various macOS-interested > people in this thread, can I ask if anybody would like to > review a couple of patches that came in at the beginning of the > year? > > https://patchew.org/QEMU/20220102174153.70043-1-carwynel...@gmail.com/ > ("ui/cocoa: Add option to disable left command and hide cursor on click") > and > https://patchew.org/QEMU/20220103114515.24020-1-carwynel...@gmail.com/ > ("Show/hide the menu bar in fullscreen on mouse") > > either from the point of view of "is this a sensible change to > the macOS UI experience" or for the actual code changes, or both. > > We've been very short on upstream macOS code reviewers so if people > interested in that host platform are able to chip in by > reviewing each others' code that helps a lot. > > thanks > -- PMM
