I've spent an inordinate amount of time fixing, upgrading and testing C++11 things in emscripten in the past.
The big gaps are: - Threads (obviously) - Atomics (fixed now and this used to work before the switch to LE32). - Some aspects of futures as these require exception features which are not supported. The big missing exception feature in this area is std::exception_ptr. - Some locale stuff since emscripten doesn't support any extra locales. Pretty much everything else has worked at some point in time on emscripten. Bugs were found in libcxx, LLVM and emscripten in the process of this testing and most have been fixed. Some bugs involving LTO were not fixed though, as far as I can recall but they might've been fixed by other changes as I haven't retested with the latest LLVM / Clang. Hope this is useful info! - Bruce On Thu, Apr 10, 2014 at 5:13 PM, Floh <[email protected]> wrote: > Thanks for implementing this Alon! > > I also just had a look at std::chrono, and it actually looks like it is > working fine (I was confused earlier because chrono::system_clock which I > was using for testing only has millisecond resolution on emscripten, but > seems to have more resolution on native OSX, however the > chrono::high_resolution_clock provides sub-millisecond accuracy in > emscripten... I think the C++11 standard doesn't mention any real accuracy > requirements, so I think emscripten's behaviour is perfectly fine. > > Apart from std::thread (naturally) I think this should cover any > platform-specifics for C++11 I think...? > > -Floh. > > Am Dienstag, 8. April 2014 01:23:15 UTC+2 schrieb Alon Zakai: > >> We need to implement those in CallHandlers.h in fastcomp, basically. Not >> too much work, and it will be expanded out inline so no call overhead. Can >> you please file a github issue with a testcase? >> >> - Alon >> >> >> >> On Mon, Apr 7, 2014 at 1:17 PM, Floh <[email protected]> wrote: >> >>> Hi, >>> >>> I was dabbling with C++11 a while ago and had code generation problems >>> with atomic operations (see here: https://groups.google. >>> com/forum/#!searchin/emscripten-discuss/C$2B$2B11$ >>> 20atomic/emscripten-discuss/UN1moUZilrM/m_Qm1KSVGrQJ) >>> >>> The good news is that this specific problem seems to be fixed with >>> clang3.4 in the fastcomp backend, however, I'm now getting linker errors >>> where LLVM wants to call CRT functions for atomic operations: >>> >>> warning: unresolved symbol: __atomic_store_1 >>> warning: unresolved symbol: __atomic_load_4 >>> warning: unresolved symbol: __atomic_load_1 >>> warning: unresolved symbol: __atomic_fetch_sub_4 >>> warning: unresolved symbol: __atomic_store_4 >>> warning: unresolved symbol: __atomic_fetch_add_4 >>> warning: unresolved symbol: __atomic_compare_exchange_4 >>> >>> I'm wondering now how to treat this type of problem onward. I'm >>> currently having ifdefs for emscripten around this code, basically treat >>> some subset of C++11 as platform-specific and have an emscripten-specific >>> implementation (which would very likely be more efficient anyway, since >>> it's just basic load/add/sub instead of calling into a function). >>> >>> Is there a plan / time-line for missing C++11 stuff, and is there a list >>> somewhere what C++11 areas don't work? I assume thread (obviously), atomic, >>> and chronos? >>> >>> These are the only areas which I had trouble with so far btw, other >>> C++11 stuff seems to work fine. >>> >>> Cheers, >>> -Floh. >>> >>> -- >>> You received this message because you are subscribed to the Google >>> Groups "emscripten-discuss" group. >>> To unsubscribe from this group and stop receiving emails from it, send >>> an email to [email protected]. >>> For more options, visit https://groups.google.com/d/optout. >>> >> >> -- > You received this message because you are subscribed to the Google Groups > "emscripten-discuss" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > For more options, visit https://groups.google.com/d/optout. > -- You received this message because you are subscribed to the Google Groups "emscripten-discuss" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
