1. 21 Aug, 2019 4 commits
  2. 20 Aug, 2019 4 commits
    • Wez Furlong's avatar
      getdeps: fixup testpilot new test recording · 1dd79077
      Wez Furlong authored
      Summary:
      In the Facebook infrastructure the testpilot runner talks
      to a service to determine whether a given test should be run locally.
      
      The remote service was returning an error for some tests because they
      didn't have enough configuration specified.
      
      This diff associates some configuration with the tests based on the
      host type and makes things happier.
      
      Reviewed By: Ben0mega
      
      Differential Revision: D16894682
      
      fbshipit-source-id: b6f59b112991160ef26cc126e98041d8908a6273
      1dd79077
    • Nathan Bronson's avatar
      add tests for sized deallocation of size zero · 2cf2b4f9
      Nathan Bronson authored
      Summary:
      Sized deallocation via ::operator delete with size == 0 is
      broken in some allocators.  This diff adds a unit test that ensures we
      are either disabling sized deallocator or running with a good allocator.
      
      Reviewed By: interwq
      
      Differential Revision: D10857654
      
      fbshipit-source-id: 981c7bcc1b021d4cd1ea1725ccf510d1958842fd
      2cf2b4f9
    • Ming Zhao's avatar
      Switch dev mode debug level from -g2 to -g1 since dev mode implies build as fast as possible. · 202eace0
      Ming Zhao authored
      Reviewed By: pixelb
      
      Differential Revision: D15301144
      
      fbshipit-source-id: f94a805427b6fc8b20e7c01fcf6e1853fbebf7f1
      202eace0
    • Victor Zverovich's avatar
      Don't fail on EINPROGRESS error in bind · 2e6e2196
      Victor Zverovich authored
      Summary: Make `AsyncServerSocket` not fail on `EINPROGRESS` in `bind` and fix handling of `errno` there.
      
      Reviewed By: yfeldblum
      
      Differential Revision: D16791566
      
      fbshipit-source-id: 1aeaefb6bae47bf41fd2d20238b716b84d0566d1
      2e6e2196
  3. 19 Aug, 2019 6 commits
    • Aaryaman Sagar's avatar
      Fix test build break · ce5afdc6
      Aaryaman Sagar authored
      Summary: T52681488
      
      Reviewed By: Orvid
      
      Differential Revision: D16901429
      
      fbshipit-source-id: 0a5fc218edf6ef29b100365163102dbdc2abf313
      ce5afdc6
    • Yedidya Feldblum's avatar
      Suppress a spurious MSVC warning in folly/Traits.h · 9bcfff7a
      Yedidya Feldblum authored
      Summary:
      [Folly] Suppress a spurious MSVC warning in `folly/Traits.h`.
      
      ```
      folly\traits.h(645): warning C4287: '>': unsigned/negative constant mismatch
      folly\traits.h(646): warning C4287: '<=': unsigned/negative constant mismatch
      folly\traits.h(647): warning C4287: '<': unsigned/negative constant mismatch
      ```
      
      Reviewed By: Orvid
      
      Differential Revision: D16889045
      
      fbshipit-source-id: 31edd58bf046143092a5f006ee0ac5b071b539a0
      9bcfff7a
    • Yedidya Feldblum's avatar
      Fix MSVC conversion warning in Optional test · 05a06785
      Yedidya Feldblum authored
      Summary:
      [Folly] Fix MSVC conversion warning in `Optional` test.
      
      ```
      folly\optional.h(372): warning C4244: 'argument': conversion from 'double' to 'int', possible loss of data
      folly\optional.h(358): note: see reference to function template instantiation 'void folly::Optional<Type>::construct<std::initializer_list<_Ty>&,double>(std::initializer_list<_Ty> &,double &&)' being compiled
                with
                [
                    _Ty=int
                ]
      folly\optional.h(359): note: see reference to function template instantiation 'void folly::Optional<Type>::construct<std::initializer_list<_Ty>&,double>(std::initializer_list<_Ty> &,double &&)' being compiled
                with
                [
                    _Ty=int
                ]
      folly\optional.h(449): note: see reference to function template instantiation 'folly::Optional<Type>::Optional<std::initializer_list<_Ty>&,double>(folly::Optional<Type>::PrivateConstructor,std::initializer_list<_Ty> &,double &&) noexcept' being compiled
                with
                [
                    _Ty=int
                ]
      folly\optional.h(451): note: see reference to function template instantiation 'folly::Optional<Type>::Optional<std::initializer_list<_Ty>&,double>(folly::Optional<Type>::PrivateConstructor,std::initializer_list<_Ty> &,double &&) noexcept' being compiled
                with
                [
                    _Ty=int
                ]
      folly\test\optionaltest.cpp(659): note: see reference to function template instantiation 'folly::Optional<Type> folly::make_optional<Type,int,double>(std::initializer_list<_Ty>,double &&)' being compiled
                with
                [
                    _Ty=int
                ]
      ```
      
      Reviewed By: Orvid
      
      Differential Revision: D16889085
      
      fbshipit-source-id: c59f5e3fa0d4402e1b836841dff66d73b111235f
      05a06785
    • Victor Zverovich's avatar
      Fix building projects that use target_compile_features · 240c1593
      Victor Zverovich authored
      Summary:
      Building a project that uses folly and `target_compile_features` may fail
      because folly requires C++14 and CMake doesn't know about it. So if a project
      has only C++11 features in `target_compile_features` CMake will pick
      `-std=gnu++11` or similar and compilation will fail on an assertion in
      `folly/Portability.h`. To fix this, add `target_compile_features` to the
      `folly` target pushing the minimum required standard to C++14.
      
      Reviewed By: Orvid
      
      Differential Revision: D16884888
      
      fbshipit-source-id: 0e5ac4abde10b1ea757011bcd05b17d508859b4f
      240c1593
    • Adam Simpkins's avatar
      fbcode_builder: CMake functions for building standalone python programs · bca45896
      Adam Simpkins authored
      Summary:
      Add some CMake functions for building standalone executables from Python
      source files.  This generates executables similar to PEX
      (https://github.com/pantsbuild/pex).
      
      In the future this could potentially be leveraged to directly build XAR files
      (https://github.com/facebookincubator/xar).
      
      The main advantages of these functions is that they allow easily defining
      "libraries" of python files, and their dependencies, which can then be used
      and packaged as part of multiple different standalone executables.
      
      Reviewed By: wez
      
      Differential Revision: D16722499
      
      fbshipit-source-id: e1d829b911dc428e5438b5cf9cebf99b3fb6ce24
      bca45896
    • Dan Melnic's avatar
      Avoid SIGSEGV if getIOExecutor() returns null · 7329a2b5
      Dan Melnic authored
      Summary: Avoid SIGSEGV if getIOExecutor() returns null
      
      Reviewed By: yfeldblum
      
      Differential Revision: D16859157
      
      fbshipit-source-id: 00c7a45677c61d84a10486f11b4f792093ac2ff5
      7329a2b5
  4. 18 Aug, 2019 2 commits
    • Orvid King's avatar
      Disable an additional warning on windows · 651dace4
      Orvid King authored
      Summary:
      It's spammy and is just informational.
      
      Created from Diffusion's 'Open in Editor' feature.
      
      Reviewed By: yfeldblum
      
      Differential Revision: D16886741
      
      fbshipit-source-id: 29aecb8a62cac9a60cbc4cabc596fd1ee00cfc04
      651dace4
    • Yedidya Feldblum's avatar
      Cut IsRelocatable of containers · cd5c885f
      Yedidya Feldblum authored
      Summary:
      [Folly] Cut IsRelocatable markings of containers, removing forward declarations of the containers to avoid over-inclusion and to avoid undefined behavior.
      
      > 16.5.4.2.1 [namespace.std]\1
      > Unless otherwise specified, the behavior of a C++ program is undefined if it adds declarations or definitions to namespace std or to a namespace within namespace std.
      
      Closes #1203.
      Closes #1204.
      
      Reviewed By: igorsugak
      
      Differential Revision: D16855473
      
      fbshipit-source-id: 0e6acc4f589707aa79b0001b415bcadfab652d62
      cd5c885f
  5. 17 Aug, 2019 4 commits
    • Yedidya Feldblum's avatar
      Revise atomic_fetch_set, atomic_fetch_reset comments · 210e404b
      Yedidya Feldblum authored
      Summary: [Folly] Revise `atomic_fetch_set`, `atomic_fetch_reset` comments, enforcing structure and switching comment style.
      
      Reviewed By: aary
      
      Differential Revision: D16877442
      
      fbshipit-source-id: 0c4c163f2daa14616f20c4e0cac1002c83ec5fac
      210e404b
    • Lucian Grijincu's avatar
      folly: add support for MLOCK_ONFAULT · d5e069c2
      Lucian Grijincu authored
      Summary:
      http://man7.org/linux/man-pages/man2/mlock.2.html
      
             MLOCK_ONFAULT
                    Lock pages that are currently resident and mark the entire
                    range so that the remaining nonresident pages are locked when
                    they are populated by a page fault.
      
      The kernel still checks a few things for `MLOCK_ONFAULT`: rlimits RLIMIT_MEMLOCK / CAP_IPC_LOCK => EPERM or ENOMEM
      
      `TRY_LOCK` & `MUST_LOCK` are only different in in their handling of EPERM, ENOMEN: whether to fail or ignore the errors, so I added a separate enum.
      
      https://github.com/torvalds/linux/blob/v5.0/mm/mlock.c#L29-L37
      ```
      bool can_do_mlock(void)
      {
      	if (rlimit(RLIMIT_MEMLOCK) != 0)
      		return true;
      	if (capable(CAP_IPC_LOCK))
      		return true;
      	return false;
      }
      EXPORT_SYMBOL(can_do_mlock);
      ```
      
      https://github.com/torvalds/linux/blob/v5.0/mm/mlock.c#L671-L714
      ```
      static __must_check int do_mlock(unsigned long start, size_t len, vm_flags_t flags)
      {
      	unsigned long locked;
      	unsigned long lock_limit;
      	int error = -ENOMEM;
      
      	if (!can_do_mlock())
      		return -EPERM;
      
      	len = PAGE_ALIGN(len + (offset_in_page(start)));
      	start &= PAGE_MASK;
      
      	lock_limit = rlimit(RLIMIT_MEMLOCK);
      	lock_limit >>= PAGE_SHIFT;
      	locked = len >> PAGE_SHIFT;
      
      	if (down_write_killable(&current->mm->mmap_sem))
      		return -EINTR;
      
      	locked += current->mm->locked_vm;
      	if ((locked > lock_limit) && (!capable(CAP_IPC_LOCK))) {
      		/*
      		 * It is possible that the regions requested intersect with
      		 * previously mlocked areas, that part area in "mm->locked_vm"
      		 * should not be counted to new mlock increment count. So check
      		 * and adjust locked count if necessary.
      		 */
      		locked -= count_mm_mlocked_page_nr(current->mm,
      				start, len);
      	}
      
      	/* check against resource limits */
      	if ((locked <= lock_limit) || capable(CAP_IPC_LOCK))
      		error = apply_vma_lock_flags(start, len, flags);
      
      	up_write(&current->mm->mmap_sem);
      	if (error)
      		return error;
      
      	error = __mm_populate(start, len, 0);
      	if (error)
      		return __mlock_posix_error_return(error);
      	return 0;
      }
      ```
      
      https://github.com/torvalds/linux/blob/v5.0/mm/mlock.c#L721-L732
      ```
      SYSCALL_DEFINE3(mlock2, unsigned long, start, size_t, len, int, flags)
      {
      	vm_flags_t vm_flags = VM_LOCKED;
      
      	if (flags & ~MLOCK_ONFAULT)
      		return -EINVAL;
      
      	if (flags & MLOCK_ONFAULT)
      		vm_flags |= VM_LOCKONFAULT;
      
      	return do_mlock(start, len, vm_flags);
      }
      
      ```
      
      Reviewed By: yfeldblum
      
      Differential Revision: D16760748
      
      fbshipit-source-id: 54937046f5faaceac2cfb9dd6a0f207ad653fe6b
      d5e069c2
    • Tristan Rice's avatar
      Future.within: cancel timeout callbacks on success · 619679d3
      Tristan Rice authored
      Summary:
      Currently the timekeeper callback set by the within method isn't cleaned up when the future resolves and always waits the full duration. This can cause OOM under high QPS and long timeout situations.
      
      This resolves this by cancelling the callback.
      
      Reviewed By: mpark
      
      Differential Revision: D16835816
      
      fbshipit-source-id: c400afc37dbc66447aaa8fd557a770d717d9ab02
      619679d3
    • Aaryaman Sagar's avatar
      Fix DistributedMutex TSAN failures for rocksdb · 83bddb4d
      Aaryaman Sagar authored
      Summary:
      RocksDB's TSAN version was not able to instrument atomic_fetch_set and
      atomic_fetch_reset; and as a result the DistributedMutex tests were failing
      under TSAN
      
      Also TSAN seems to have some issue when and exception_ptr is placed into an
      aligned_storage_t instance. This verifiably correct program (I think) also fails
      with the same TSAN error P78696506. So
      disable that test
      
      This is the code with the same false-negative
      ```
      namespace {
      class ExceptionWithConstructionTrack : public std::exception {
       public:
        explicit ExceptionWithConstructionTrack(int id)
            : id_{folly::to<std::string>(id)}, constructionTrack_{id} {}
      
        const char* what() const noexcept override {
          return id_.c_str();
        }
      
       private:
        std::string id_;
        TestConstruction constructionTrack_;
      };
      
      template <typename Storage, typename Atomic>
      void transferCurrentException(Storage& storage, Atomic& produced) {
        assert(std::current_exception());
        new (&storage) std::exception_ptr(std::current_exception());
        produced->store(true, std::memory_order_release);
      }
      
      void concurrentExceptionPropagationStress(
          int numThreads,
          std::chrono::milliseconds milliseconds) {
        auto&& stop = std::atomic<bool>{false};
        auto&& exceptions = std::vector<std::aligned_storage<48, 8>::type>{};
        auto&& produced = std::vector<std::unique_ptr<std::atomic<bool>>>{};
        auto&& consumed = std::vector<std::unique_ptr<std::atomic<bool>>>{};
        auto&& consumers = std::vector<std::thread>{};
        for (auto i = 0; i < numThreads; ++i) {
          produced.emplace_back(new std::atomic<bool>{false});
          consumed.emplace_back(new std::atomic<bool>{false});
          exceptions.push_back({});
        }
      
        auto producer = std::thread{[&]() {
          auto counter = std::vector<int>(numThreads, 0);
          for (auto i = 0; true; i = ((i + 1) % numThreads)) {
            try {
              throw ExceptionWithConstructionTrack{counter.at(i)++};
            } catch (...) {
              transferCurrentException(exceptions.at(i), produced.at(i));
            }
      
            while (!consumed.at(i)->load(std::memory_order_acquire)) {
              if (stop.load(std::memory_order_acquire)) {
                return;
              }
            }
      
            consumed.at(i)->store(false, std::memory_order_release);
          }
        }};
      
        for (auto i = 0; i < numThreads; ++i) {
          consumers.emplace_back([&, i]() {
            auto counter = 0;
            while (true) {
              while (!produced.at(i)->load(std::memory_order_acquire)) {
                if (stop.load(std::memory_order_acquire)) {
                  return;
                }
              }
              produced.at(i)->store(false, std::memory_order_release);
      
              try {
                auto storage = &exceptions.at(i);
                auto exc = folly::launder(
                  reinterpret_cast<std::exception_ptr*>(storage));
                auto copy = std::move(*exc);
                exc->std::exception_ptr::~exception_ptr();
                std::rethrow_exception(std::move(copy));
              } catch (std::exception& exc) {
                auto value = std::stoi(exc.what());
                EXPECT_EQ(value, counter++);
              }
      
              consumed.at(i)->store(true, std::memory_order_release);
            }
          });
        }
      
        std::this_thread::sleep_for(milliseconds);
        stop.store(true);
        producer.join();
        for (auto& thread : consumers) {
          thread.join();
        }
      }
      } // namespace
      ```
      
      Reviewed By: yfeldblum
      
      Differential Revision: D16739396
      
      fbshipit-source-id: 0eba191ffc07d2e64a3ea550c5fe9a7d01ce2f18
      83bddb4d
  6. 16 Aug, 2019 7 commits
    • Aaryaman Sagar's avatar
      Define sanitize macros if they weren't already defined · d5c4abb3
      Aaryaman Sagar authored
      Summary: As title
      
      Reviewed By: yfeldblum
      
      Differential Revision: D16821444
      
      fbshipit-source-id: 14f0655caf0f53ef47fa65b9b6ba57f0f190df12
      d5c4abb3
    • Yedidya Feldblum's avatar
      #define FOLLY_ERASE FOLLY_ALWAYS_INLINE FOLLY_ATTR_VISIBILITY_HIDDEN · e7a9b358
      Yedidya Feldblum authored
      Summary: [Folly] `#define FOLLY_ERASE FOLLY_ALWAYS_INLINE FOLLY_ATTR_VISIBILITY_HIDDEN`.
      
      Reviewed By: vitaut
      
      Differential Revision: D16686469
      
      fbshipit-source-id: cedaee61955a40ae28ad2b0da565fc9fb385bc6e
      e7a9b358
    • Adam Simpkins's avatar
      getdeps: distinguish build vs install steps in run_cmake.py · 9876b788
      Adam Simpkins authored
      Summary:
      Update the generated `run_cmake.py` script to allow the caller to specify that
      they just want to run a build without the install step.
      
      Reviewed By: wez
      
      Differential Revision: D16778007
      
      fbshipit-source-id: 1859aca2b80fa7b099b4790682a6508e0185f2a0
      9876b788
    • Adam Simpkins's avatar
      getdeps: honor INSTALL_DIR correctly in the generated run_cmake.py script · 1bfbd0d8
      Adam Simpkins authored
      Summary:
      This cleans up how the `CMAKE_ENV` and `CMAKE_DEFINE_ARGS` variables are
      written in the generated `run_cmake.py` script that we emit for CMake-based
      projects.
      
      We now emit each entry in these variables on separate lines, just to improve
      readability.  (Both of these variables tend to have a number of entries and
      are very long if emitted on a single line.)
      
      This also replaces the `-DCMAKE_INSTALL_PREFIX` entry in `CMAKE_DEFINE_ARGS`
      to have it correctly honor the `INSTALL_DIR` variable defined in
      `run_cmake.py`.  This makes `run_cmake.py` still do the right thing if someone
      manually edits it to change the `INSTALL_DIR` value.
      
      Reviewed By: wez
      
      Differential Revision: D16778006
      
      fbshipit-source-id: fee5d25748b87b5d9c57ee2edf8de5e586e872ee
      1bfbd0d8
    • Adam Simpkins's avatar
      getdeps: allow overriding project source, build, and install directories · 8479be08
      Adam Simpkins authored
      Summary:
      Add arguments to getdeps.py to allow overriding the source, build, and install
      directories a per-project basis.  The arguments take the form `[PROJECT:]PATH`
      If the `PROJECT` portion is omitted, it defaults to the current project being
      built.
      
      In particular this makes it possible to specify `--src-dir .` to tell
      getdeps.py to find the project sources from the current directory rather than
      downloading them.
      
      Reviewed By: wez
      
      Differential Revision: D16778011
      
      fbshipit-source-id: f33b87213ace04abb66334f588babdf59df91964
      8479be08
    • Adam Simpkins's avatar
      getdeps: fix a crash if the project_hashes directory does not exist · 4ce59c1d
      Adam Simpkins authored
      Summary:
      This makes getdeps.py no longer crash if used in the folly repository.
      Folly does not depend on any other Facebook projects, so it does not
      include a `build/deps` directory.
      
      Reviewed By: wez
      
      Differential Revision: D16778009
      
      fbshipit-source-id: 41be53d862f41b62154b081eb90ddba8742658fe
      4ce59c1d
    • Adam Simpkins's avatar
      getdeps: consolidate code for project subcommands · 27bf440a
      Adam Simpkins authored
      Summary:
      Most of the getdeps subcommands operate on a single project, and some of the
      argument parsing and initial logic to load the project is largely the same.
      This consolidates that logic into a base class so that we can share this code
      across subcommands, instead of repeating it.
      
      This also unifies the behavior so that by default all commands enable tests on
      the specified project, and disable test on dependent projects.  Making sure
      all commands use the same behavior here is important as whether are not tests
      are enabled can affect the project configuration, and therefore affect its
      getdeps hash.
      
      Reviewed By: wez
      
      Differential Revision: D16778010
      
      fbshipit-source-id: 044f99ad6cdd4a56f843276cec8ead786249ee7a
      27bf440a
  7. 15 Aug, 2019 3 commits
  8. 14 Aug, 2019 2 commits
    • Mark Santaniello's avatar
      more pmr support for sorted_vector_types · 66270d4e
      Mark Santaniello authored
      Summary:
      - Add allocator-extended copy constructors
      - Add allocator-extended move constructors
      - Add allocator-extended initializer-list constructor
      - Add get_allocator accessor
      - Make emplace/emplace_hint use the allocator
      - pmr tests catch allocations that "escape" by setting the default resource to null
      
      Reviewed By: nbronson
      
      Differential Revision: D16623448
      
      fbshipit-source-id: c10682f98d1c234fcad95608643b2f3ccea64a41
      66270d4e
    • Mark Santaniello's avatar
      mark small_vector get_allocator() as const · f9b0a56b
      Mark Santaniello authored
      Summary: This function should be marked const.
      
      Reviewed By: yfeldblum
      
      Differential Revision: D16793980
      
      fbshipit-source-id: 3e98f999c3e00caa0d238fa29c082ab6e819bf2a
      f9b0a56b
  9. 13 Aug, 2019 1 commit
    • Adam Simpkins's avatar
      getdeps: fix handling of the --host-type command line flag · 9f73ab95
      Adam Simpkins authored
      Summary:
      Fix the BuildOptions class to correctly honor the `host_type` parameter that
      it was constructed with when constructing the manifest evaluation context.
      I accidentally broke this behavior in D16477396, and incorrectly had this code
      path default to using the current host system rather than the value passed in
      from the command line.
      
      Reviewed By: wez
      
      Differential Revision: D16779579
      
      fbshipit-source-id: de911daaa643f6303fd35149775ab25d3f64d34f
      9f73ab95
  10. 12 Aug, 2019 2 commits
  11. 11 Aug, 2019 1 commit
    • Nathan Bronson's avatar
      fix SwapTrackingAlloc initial conditions · 59799039
      Nathan Bronson authored
      Summary:
      This diff fixes the initial conditions for SwapTrackingAlloc,
      which fixes F14 tests on platforms that do not have intrinsics enabled.
      
      Differential Revision: D16755857
      
      fbshipit-source-id: a76d8093100cbc0c5ce8723daa0976673d942299
      59799039
  12. 10 Aug, 2019 1 commit
    • Nathan Bronson's avatar
      reusable key destructuring logic for implementing emplace · a44b291c
      Nathan Bronson authored
      Summary:
      This diff extracts the key destructuring logic in F14's emplace
      functions into standalone helpers that can be used by other container
      types (like sorted_vector_{set,map}).  It also adds better PMR compliance, by
      using a stateful allocator to construct a temporary if that is required
      to be able to perform the search.
      
      This diff also cleans up some of the testing code in folly/container/test
      that had issues if included in multiple places.
      
      Reviewed By: yfeldblum
      
      Differential Revision: D16655131
      
      fbshipit-source-id: 5a6f57ac346d1fd5928e0f737110760b0c518974
      a44b291c
  13. 09 Aug, 2019 1 commit
    • Adam Simpkins's avatar
      getdeps: make sure ManifestLoader never reloads manifests · 120ac01a
      Adam Simpkins authored
      Summary:
      In response to review feedback for D16477400 and D16477401, update
      `ManifestLoader.load_all_manifests()` to only update its data for projects
      that have not previously been loaded.  This helps ensure that code using a
      single `ManifestLoader` object cannot have two in-memory `Manifest` objects
      for the same project, and that existing data (such as project hashes) can't be
      invalidated if a manifest is later loaded from updated on-disk data.
      
      Reviewed By: pkaush
      
      Differential Revision: D16586682
      
      fbshipit-source-id: 50b1979ec55f2ad6901629cd852293a8f6ca903f
      120ac01a
  14. 08 Aug, 2019 2 commits
    • Christos Stratopoulos's avatar
      Add noexcept-qualified versions of `IsConstMember` (#1201) · 6e123842
      Christos Stratopoulos authored
      Summary:
      This is a missing piece from https://github.com/facebook/folly/pull/1178, but more nasty as it can cause runtime rather than compile-time failures.
      
      Given an interface `ICat` with `void meow() const`, if we have `struct cat` with `void meow() const noexcept`, then constructing a `folly::Poly<ICat const&>` for an instance of `cat` will have a null pointer in the vtable entry for the `meow` method.
      
      The culprit seems to be in the template specialization for [`ThunkFn` ](https://github.com/cstratopoulos/folly/blob/feature/poly-update/folly/detail/PolyDetail.h#L539) which may be dispatched on `IsConstMember`.
      
      I've added a fairly trivial test case to `PolyTest.cpp`; but notably it is the only instance of _any_ test case in that file having a `noexcept` method. Without the change in `PolyDetail.h`, the call to `cref->meow()` will cause a null pointer dereference. If something more explicit is desired, maybe we could `EXPECT` that the corresponding vtable entry is non-null, but that doesn't exactly fit the pattern of other test cases in that file.
      
      (Aside: In the linked PR I used `__cpp_noexcept_function_type` directly, but I have since realized that a macro for this is already present in [`Portability.h`](https://github.com/facebook/folly/blob/master/folly/Portability.h#L503) so I'm using that one now)
      Pull Request resolved: https://github.com/facebook/folly/pull/1201
      
      Reviewed By: ericniebler
      
      Differential Revision: D16686139
      
      Pulled By: yfeldblum
      
      fbshipit-source-id: 73c7ac132d6e772ffd49f450b5fcd0f8a0dbdb26
      6e123842
    • Claire (Yue) Zhang's avatar
      Add boundary support into Cursor · 6b2c52f3
      Claire (Yue) Zhang authored
      Summary:
      Added boundary support in folly/io/Cursor.h.
      
      The bounded Cursor can have a boundary that is shorter than the underlying IOBuf. This gives a custom view of the IOBuf.
      
      Reviewed By: spalamarchuk
      
      Differential Revision: D16347838
      
      fbshipit-source-id: 16d91e42e2acee788b31bc2a9b6cc8716b1d22f2
      6b2c52f3