njames93 added inline comments.
================ Comment at: llvm/include/llvm/Support/ManagedStatic.h:25 +// that are const with no params. +template <typename T> struct HasRetainRelease { +private: ---------------- dblaikie wrote: > njames93 wrote: > > dblaikie wrote: > > > Are there many uses that rely on this? I don't think it's really worth > > > all this infrastructure - compared to having it supported on an as-needed > > > basis, such as directly in TrueMatcherImpl's ctor and dtor. > > It doesn't work in TrueMatcherImpl ctor/dtor due to the whole double free > > issue(See [[ https://reviews.llvm.org/D92480#inline-864517 | previous > > comment ]]). I can go back to just supporting it for TrueMatcherImpl by > > writing a single custom creator/deleter for that class. > > > > This approach taken was a little overkill but likely a little more > > foolproof for someone using the library. I'll go ahead with whichever > > approach you would prefer. > Ah, right - thanks for walking me through it again, now I better understand > your previous comment - sorry for that erroneous suggestion/confusion. > > Fair points all. > > Given all that, I'm sort of leaning towards the idea that maybe the right > solution here is for the `TrueMatcherInstance` bear the cost of the > complexity here (if it's the only one) with something like: > > ``` > struct TrueMatcherImplCreator { > static void *call() { > return new IntrusiveRefCntPtr<TrueMatcherImpl>(new TrueMatcherImpl()); > } > }; > static llvm::ManagedStatic<IntrusiveRefCntPtr<TrueMatcherImpl>, > TrueMatcherImplCreator> TrueMatcherInstance; > ``` > > I worry about creating a fairly generic extension point for customizing how > elements in ManagedStatic can be constructed and destroyed via specialization > rather than via explicit creator/destroyer parameters. > > And while the custom destroyer is a bit simpler mechanically (doesn't involve > dynamically allocating an IntrusiveCntPtr, which is unintuitive to say the > least) - I think sticking to the "if you ever share ownership of a > RefCountedBase object, you must've allocated it with 'new' and be really > sharing ownership - no lies" is probably a healthier model for > RefCountedBase/IntrusiveRefCntPtr. Decided to take a step back. This is trying to fix a problem that's only here because we are using a `ManagedStatic`. when its not needed. A function scope static has nearly the same semantics of `ManagedStatic` and as this is only used in one function it seems a much better fit. Repository: rG LLVM Github Monorepo CHANGES SINCE LAST ACTION https://reviews.llvm.org/D92480/new/ https://reviews.llvm.org/D92480 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits