Repository: man-group/ArcticDB (language: python)

Issue:
Using QueryBuilder on grouping column with floats fails on Linux Conda
### Describe the bug

Using QueryBuilder on grouping column with floats fails on Linux Conda.
The bigger problem is that this doesn't reproduce on all versions.
It has been experienced only on Linux Conda on self-hosted ec2 runners and only on release builds.

Can be reproduced with the following test - test_group_on_float_column_with_nans

### Steps/Code to Reproduce

``` python 
ac = Arctic("lmdb://test_dir")
ac.create_library("some_lib")
lib = ac["some_lib"]
sym = "test_group_on_float_column_with_nans"
df = pd.DataFrame({"grouping_column": [1.0, 2.0, np.nan, 1.0, 2.0, 2.0], "agg_column": [1, 2, 3, 4, 5, 6]})
lib.write(sym, df)
expected = df.groupby("grouping_column").agg({"agg_column": "sum"})
q = QueryBuilder()
q = q.groupby("grouping_column").agg({"agg_column": "sum"})
received = lib.read(sym, query_builder=q).data
received.sort_index(inplace=True)
assert_frame_equal(expected, received)
```

### Expected Results

The columns are correctly grouped like this:

1.0                       5
2.0                      13

### OS, Python Version and ArcticDB Version

Python: 3.10.13 | packaged by conda-forge | (main, Oct 26 2023, 18:07:37) [GCC 12.3.0]
OS: Linux-6.2.0-1015-aws-x86_64-with-glibc2.35
ArcticDB: 1.4.1.dev0

### Backend storage used

LMDB

### Additional Context

_No response_


Discussion / hints:
This error sporadically happens on `master` already for Linux conda-build only.

For instance see: https://github.com/man-group/ArcticDB/actions/runs/6801380964/job/18492095030#step:10:502

I cannot reproduce locally. :confused: 

<details>
<summary>conda environment specification</summary>

```
conda env export
```

```yaml
name: adb
channels:
  - conda-forge
  - nodefaults
dependencies:
  - _libgcc_mutex=0.1=conda_forge
  - _openmp_mutex=4.5=2_gnu
  - annotated-types=0.6.0=pyhd8ed1ab_0
  - anyio=4.0.0=pyhd8ed1ab_0
  - asttokens=2.4.1=pyhd8ed1ab_0
  - asv=0.6.1=py310hc6cd4ac_1
  - asv_runner=0.1.0=pyhd8ed1ab_0
  - attrs=23.1.0=pyh71513ae_1
  - aws-c-auth=0.7.3=h28f7589_1
  - aws-c-cal=0.6.1=hc309b26_1
  - aws-c-common=0.9.0=hd590300_0
  - aws-c-compression=0.2.17=h4d4d85c_2
  - aws-c-event-stream=0.3.1=h2e3709c_4
  - aws-c-http=0.7.11=h00aa349_4
  - aws-c-io=0.13.32=he9a53bd_1
  - aws-c-mqtt=0.9.3=hb447be9_1
  - aws-c-s3=0.3.14=hf3aad02_1
  - aws-c-sdkutils=0.1.12=h4d4d85c_1
  - aws-checksums=0.1.17=h4d4d85c_1
  - aws-crt-cpp=0.21.0=hb942446_5
  - aws-sam-translator=1.79.0=pyhd8ed1ab_0
  - aws-sdk-cpp=1.10.57=h85b1a90_19
  - aws-xray-sdk=2.12.1=pyhd8ed1ab_0
  - azure-core=1.29.5=pyhd8ed1ab_0
  - azure-core-cpp=1.10.3=h91d86a7_0
  - azure-identity=1.15.0=pyhd8ed1ab_0
  - azure-identity-cpp=1.5.1=hf1915f5_1
  - azure-storage-blob=12.19.0=pyhd8ed1ab_0
  - azure-storage-blobs-cpp=12.10.0=h00ab1b0_0
  - azure-storage-common-cpp=12.5.0=h755215e_1
  - backports=1.0=pyhd8ed1ab_3
  - backports.functools_lru_cache=1.6.5=pyhd8ed1ab_0
  - backports.zoneinfo=0.2.1=py310hff52083_8
  - bcrypt=4.0.1=py310hcb5633a_1
  - binutils=2.40=hdd6e379_0
  - binutils_impl_linux-64=2.40=hf600244_0
  - binutils_linux-64=2.40=hbdbef99_2
  - bitmagic=7.13.4=ha770c72_0
  - blinker=1.7.0=pyhd8ed1ab_0
  - boost-cpp=1.82.0=h44aadfe_6
  - boto3=1.28.83=pyhd8ed1ab_0
  - botocore=1.31.83=pyhd8ed1ab_0
  - brotli-python=1.0.9=py310hd8f1fbe_9
  - bzip2=1.0.8=hd590300_5
  - c-ares=1.21.0=hd590300_0
  - c-compiler=1.6.0=hd590300_0
  - ca-certificates=2023.7.22=hbcca054_0
  - certifi=2023.7.22=pyhd8ed1ab_0
  - cffi=1.16.0=py310h2fee648_0
  - cfn-lint=0.83.1=pyhd8ed1ab_0
  - charset-normalizer=3.3.2=pyhd8ed1ab_0
  - click=8.1.7=unix_pyh707e725_0
  - cmake=3.27.6=hcfe8598_0
  - colorama=0.4.6=pyhd8ed1ab_0
  - contextlib2=21.6.0=pyhd8ed1ab_0
  - cryptography=41.0.5=py310h75e40e8_0
  - cxx-compiler=1.6.0=h00ab1b0_0
  - cyrus-sasl=2.1.27=h54b06d7_7
  - decorator=5.1.1=pyhd8ed1ab_0
  - dnspython=2.4.2=pyhd8ed1ab_1
  - docker-py=6.1.3=pyhd8ed1ab_0
  - double-conversion=3.3.0=h59595ed_0
  - doxygen=1.9.8=h661eb56_0
  - ecdsa=0.18.0=pyhd8ed1ab_1
  - exceptiongroup=1.1.3=pyhd8ed1ab_0
  - execnet=2.0.2=pyhd8ed1ab_0
  - executing=2.0.1=pyhd8ed1ab_0
  - flask=3.0.0=pyhd8ed1ab_0
  - flask_cors=3.0.10=pyhd3deb0d_0
  - fmt=9.1.0=h924138e_0
  - folly=2023.11.06.00=hbc8c634_0_jemalloc
  - future=0.18.3=pyhd8ed1ab_0
  - gcc=12.3.0=h8d2909c_2
  - gcc_impl_linux-64=12.3.0=he2b93b0_2
  - gcc_linux-64=12.3.0=h76fc315_2
  - gflags=2.2.2=he1b5a44_1004
  - glog=0.6.0=h6f12383_0
  - gmp=6.2.1=h58526e2_0
  - gmpy2=2.1.2=py310h3ec546c_1
  - graphql-core=3.2.3=pyhd8ed1ab_0
  - grpcio=1.54.3=py310heca2aa9_0
  - grpcio-tools=1.54.2=py310hc6cd4ac_1
  - gtest=1.14.0=h00ab1b0_1
  - gxx=12.3.0=h8d2909c_2
  - gxx_impl_linux-64=12.3.0=he2b93b0_2
  - gxx_linux-64=12.3.0=h8a814eb_2
  - h11=0.14.0=pyhd8ed1ab_0
  - h2=4.1.0=pyhd8ed1ab_0
  - hpack=4.0.0=pyh9f0ad1d_0
  - httpcore=1.0.1=pyhd8ed1ab_0
  - hyperframe=6.0.1=pyhd8ed1ab_0
  - hypothesis=6.72.4=pyha770c72_0
  - icu=73.2=h59595ed_0
  - idna=3.4=pyhd8ed1ab_0
  - importlib-metadata=6.8.0=pyha770c72_0
  - importlib_metadata=6.8.0=hd8ed1ab_0
  - importlib_resources=6.1.1=pyhd8ed1ab_0
  - iniconfig=2.0.0=pyhd8ed1ab_0
  - ipython=8.17.2=pyh41d4057_0
  - isodate=0.6.1=pyhd8ed1ab_0
  - itsdangerous=2.1.2=pyhd8ed1ab_0
  - jedi=0.19.1=pyhd8ed1ab_0
  - jemalloc=5.3.0=hcb278e6_0
  - jinja2=3.1.2=pyhd8ed1ab_1
  - jmespath=1.0.1=pyhd8ed1ab_0
  - jschema-to-python=1.2.3=pyhd8ed1ab_0
  - json5=0.9.14=pyhd8ed1ab_0
  - jsondiff=2.0.0=pyhd8ed1ab_0
  - jsonpatch=1.33=pyhd8ed1ab_0
  - jsonpickle=3.0.2=pyhd8ed1ab_1
  - jsonpointer=2.4=py310hff52083_3
  - jsonschema=4.19.2=pyhd8ed1ab_0
  - jsonschema-path=0.3.1=pyhd8ed1ab_0
  - jsonschema-specifications=2023.7.1=pyhd8ed1ab_0
  - junit-xml=1.9=pyh9f0ad1d_0
  - kernel-headers_linux-64=2.6.32=he073ed8_16
  - keyutils=1.6.1=h166bdaf_0
  - krb5=1.21.2=h659d440_0
  - lazy-object-proxy=1.9.0=py310h2372a71_1
  - ld_impl_linux-64=2.40=h41732ed_0
  - libabseil=20230125.3=cxx17_h59595ed_0
  - libaio=0.3.113=h166bdaf_0
  - libarrow=12.0.1=hb87d912_8_cpu
  - libblas=3.9.0=19_linux64_openblas
  - libboost=1.82.0=h6fcfa73_6
  - libboost-devel=1.82.0=h00ab1b0_6
  - libboost-headers=1.82.0=ha770c72_6
  - libbrotlicommon=1.0.9=h166bdaf_9
  - libbrotlidec=1.0.9=h166bdaf_9
  - libbrotlienc=1.0.9=h166bdaf_9
  - libbson=1.23.2=hcb278e6_0
  - libcblas=3.9.0=19_linux64_openblas
  - libcrc32c=1.1.2=h9c3ff4c_0
  - libcurl=8.4.0=hca28451_0
  - libedit=3.1.20191231=he28a2e2_2
  - libev=4.33=h516909a_1
  - libevent=2.1.12=hf998b51_1
  - libexpat=2.5.0=hcb278e6_1
  - libffi=3.4.2=h7f98852_5
  - libgcc-devel_linux-64=12.3.0=h8bca6fd_2
  - libgcc-ng=13.2.0=h807b86a_2
  - libgfortran-ng=13.2.0=h69a702a_2
  - libgfortran5=13.2.0=ha4646dd_2
  - libgomp=13.2.0=h807b86a_2
  - libgoogle-cloud=2.12.0=hac9eb74_1
  - libgrpc=1.54.3=hb20ce57_0
  - libiconv=1.17=h166bdaf_0
  - libjemalloc=5.3.0=hcb278e6_0
  - liblapack=3.9.0=19_linux64_openblas
  - libmongoc=1.23.2=haec5f90_0
  - libmongocxx=3.7.2=h59595ed_1
  - libnghttp2=1.58.0=h47da74e_0
  - libnsl=2.0.1=hd590300_0
  - libntlm=1.4=h7f98852_1002
  - libnuma=2.0.16=h0b41bf4_1
  - libopenblas=0.3.24=pthreads_h413a1c8_0
  - libprotobuf=3.21.12=hfc55251_2
  - libsanitizer=12.3.0=h0f45ef3_2
  - libsodium=1.0.18=h36c2ea0_1
  - libsqlite=3.44.0=h2797004_0
  - libssh2=1.11.0=h0841786_0
  - libstdcxx-devel_linux-64=12.3.0=h8bca6fd_2
  - libstdcxx-ng=13.2.0=h7e041cc_2
  - libthrift=0.18.1=h8fd135c_2
  - libutf8proc=2.8.0=h166bdaf_0
  - libuuid=2.38.1=h0b41bf4_0
  - libuv=1.46.0=hd590300_0
  - libxml2=2.11.5=h232c23b_1
  - libzlib=1.2.13=hd590300_5
  - lmdb=0.9.22=h14c3975_1000
  - lmdbxx=0.9.14.0=h00ab1b0_1
  - lz4-c=1.9.4=hcb278e6_0
  - markupsafe=2.1.3=py310h2372a71_1
  - matplotlib-inline=0.1.6=pyhd8ed1ab_0
  - mock=5.1.0=pyhd8ed1ab_0
  - moto=4.2.7=pyhd8ed1ab_0
  - mpc=1.3.1=hfe3b2da_0
  - mpfr=4.2.1=h9458935_0
  - mpmath=1.3.0=pyhd8ed1ab_0
  - msal=1.25.0=pyhd8ed1ab_0
  - msal_extensions=1.0.0=pyhd8ed1ab_0
  - msgpack-c=6.0.0=hfc55251_1
  - msgpack-python=1.0.6=py310hd41b1e2_0
  - ncurses=6.4=h59595ed_2
  - networkx=3.2.1=pyhd8ed1ab_0
  - numpy=1.26.0=py310hb13e2d6_0
  - openapi-schema-validator=0.6.2=pyhd8ed1ab_0
  - openapi-spec-validator=0.7.1=pyhd8ed1ab_0
  - openssl=3.1.4=hd590300_0
  - orc=1.9.0=h2f23424_1
  - packaging=23.2=pyhd8ed1ab_0
  - pandas=2.1.2=py310hcc13569_0
  - paramiko=3.3.1=pyhd8ed1ab_0
  - parso=0.8.3=pyhd8ed1ab_0
  - path=16.7.1=py310hff52083_1
  - path.py=12.5.0=0
  - pathable=0.4.3=pyhd8ed1ab_0
  - pbr=6.0.0=pyhd8ed1ab_0
  - pcre=8.45=h9c3ff4c_0
  - pexpect=4.8.0=pyh1a96a4e_2
  - pickleshare=0.7.5=py_1003
  - pip=23.3.1=pyhd8ed1ab_0
  - pkgutil-resolve-name=1.3.10=pyhd8ed1ab_1
  - pluggy=1.3.0=pyhd8ed1ab_0
  - portalocker=2.8.2=py310hff52083_1
  - prometheus-cpp=1.1.0=h751d214_1
  - prompt-toolkit=3.0.39=pyha770c72_0
  - prompt_toolkit=3.0.39=hd8ed1ab_0
  - protobuf=4.21.12=py310heca2aa9_0
  - psutil=5.9.5=py310h2372a71_1
  - ptyprocess=0.7.0=pyhd3deb0d_0
  - pure_eval=0.2.2=pyhd8ed1ab_0
  - py=1.11.0=pyh6c4a22f_0
  - pyarrow=12.0.1=py310h0576679_8_cpu
  - pyasn1=0.5.0=pyhd8ed1ab_0
  - pybind11=2.10.4=py310hdf3cbec_0
  - pybind11-global=2.10.4=py310hdf3cbec_0
  - pycparser=2.21=pyhd8ed1ab_0
  - pydantic=2.4.2=pyhd8ed1ab_1
  - pydantic-core=2.10.1=py310hcb5633a_0
  - pygments=2.16.1=pyhd8ed1ab_0
  - pyjwt=2.8.0=pyhd8ed1ab_0
  - pymongo=4.6.0=py310hc6cd4ac_0
  - pympler=1.0.1=pyhd8ed1ab_0
  - pynacl=1.5.0=py310h2372a71_3
  - pyparsing=3.1.1=pyhd8ed1ab_0
  - pysocks=1.7.1=pyha2e5f31_6
  - pytest=7.4.3=pyhd8ed1ab_0
  - pytest-fixture-config=1.7.0=py_0
  - pytest-server-fixtures=1.7.0=pyhd8ed1ab_0
  - pytest-shutil=1.7.0=pyhd8ed1ab_1
  - pytest-sugar=0.9.7=pyhd8ed1ab_1
  - python=3.10.13=hd12c33a_0_cpython
  - python-dateutil=2.8.2=pyhd8ed1ab_0
  - python-jose=3.3.0=pyh6c4a22f_1
  - python-tzdata=2023.3=pyhd8ed1ab_0
  - python_abi=3.10=4_cp310
  - pytz=2023.3.post1=pyhd8ed1ab_0
  - pywin32-on-windows=0.1.0=pyh1179c8e_3
  - pyyaml=6.0.1=py310h2372a71_1
  - rapidcheck=2023.4.13=h00ab1b0_2
  - rdma-core=28.9=h59595ed_1
  - re2=2023.03.02=h8c504da_0
  - readline=8.2=h8228510_1
  - recycle=6.0.0=h00ab1b0_1
  - referencing=0.30.2=pyhd8ed1ab_0
  - regex=2023.10.3=py310h2372a71_0
  - requests=2.31.0=pyhd8ed1ab_0
  - responses=0.24.0=pyhd8ed1ab_0
  - retry=0.9.2=py_0
  - rfc3339-validator=0.1.4=pyhd8ed1ab_0
  - rhash=1.4.4=hd590300_0
  - robin_hood=3.11.5=h00ab1b0_1
  - rpds-py=0.12.0=py310hcb5633a_0
  - rsa=4.9=pyhd8ed1ab_0
  - s2n=1.3.49=h06160fa_0
  - s3transfer=0.7.0=pyhd8ed1ab_0
  - sarif-om=1.0.4=pyhd8ed1ab_0
  - semimap=1.0.0=h00ab1b0_1
  - setuptools=68.2.2=pyhd8ed1ab_0
  - six=1.16.0=pyh6c4a22f_0
  - snappy=1.1.10=h9fff704_0
  - sniffio=1.3.0=pyhd8ed1ab_0
  - sortedcontainers=2.4.0=pyhd8ed1ab_0
  - spdlog=1.12.0=h5743cc6_0
  - sshpubkeys=3.3.1=pyhd8ed1ab_0
  - stack_data=0.6.2=pyhd8ed1ab_0
  - sympy=1.12=pypyh9d50eac_103
  - sysroot_linux-64=2.12=he073ed8_16
  - tabulate=0.9.0=pyhd8ed1ab_1
  - termcolor=2.3.0=pyhd8ed1ab_0
  - tk=8.6.13=noxft_h4845f30_101
  - tomli=2.0.1=pyhd8ed1ab_0
  - traitlets=5.13.0=pyhd8ed1ab_0
  - types-pyyaml=6.0.12.12=pyhd8ed1ab_0
  - typing-extensions=4.8.0=hd8ed1ab_0
  - typing_extensions=4.8.0=pyha770c72_0
  - tzdata=2023c=h71feb2d_0
  - ucx=1.14.1=h64cca9d_5
  - urllib3=1.26.18=pyhd8ed1ab_0
  - wcwidth=0.2.9=pyhd8ed1ab_0
  - websocket-client=1.6.4=pyhd8ed1ab_0
  - werkzeug=3.0.1=pyhd8ed1ab_0
  - wheel=0.41.3=pyhd8ed1ab_0
  - wrapt=1.16.0=py310h2372a71_0
  - xmltodict=0.13.0=pyhd8ed1ab_0
  - xxhash=0.8.2=hd590300_0
  - xz=5.2.6=h166bdaf_0
  - yaml=0.2.5=h7f98852_2
  - zipp=3.17.0=pyhd8ed1ab_0
  - zlib=1.2.13=hd590300_5
  - zstd=1.5.5=hfc55251_0
  - pip:
      - arcticdb==4.1.0.dev0
prefix: /home/jjerphan/.local/share/mambaforge/envs/adb
```

</details>
We're on `v0.6.5`, which was released in April 2018. It seems to be quite actively maintained, and `v0.8.2` was released in July 2023, we should try upgrading to the latest version in case they fixed the issue in the interim.

Fix patch:
diff --git a/cpp/arcticdb/CMakeLists.txt b/cpp/arcticdb/CMakeLists.txt
index b3b600a55f..113fc8549d 100644
--- a/cpp/arcticdb/CMakeLists.txt
+++ b/cpp/arcticdb/CMakeLists.txt
@@ -35,6 +35,7 @@ endif()
 find_package(Protobuf REQUIRED)
 find_package(mongocxx REQUIRED)
 find_package(bsoncxx REQUIRED)
+find_package(xxHash REQUIRED)
 find_package(zstd CONFIG REQUIRED)  # "CONFIG" bypasses our cpp/CMake/FindZstd.cmake module
 
 find_package(azure-identity-cpp CONFIG REQUIRED)
@@ -66,7 +67,6 @@ else()
     SET(HIDE_LINKED_SYMBOLS OFF)
 
     find_package(pybind11 REQUIRED)
-    find_package(xxHash REQUIRED)
     find_package(PCRE REQUIRED)
     find_package(Libevent  REQUIRED)
     find_package(semimap REQUIRED)
@@ -90,7 +90,12 @@ else()
     list(REMOVE_ITEM NEW_FOLLY_DEPS "/usr/local/opt/openssl/include" )
     set_target_properties(Folly::folly_deps PROPERTIES INTERFACE_INCLUDE_DIRECTORIES "${NEW_FOLLY_DEPS}")
 
+    add_library(xxHash STATIC IMPORTED)
+    set_target_properties(xxHash PROPERTIES IMPORTED_LOCATION ${xxHash_LIBRARY})
+    set_target_properties(xxHash PROPERTIES INTERFACE_INCLUDE_DIRECTORIES ${xxHash_INCLUDE_DIR})
+
 endif()
+
 # RocksDB can be manually excluded with set(ARCTICDB_INCLUDE_ROCKSDB 0)
 # Default is to include on PyPI builds and exclude on conda builds
 if(${ARCTICDB_INCLUDE_ROCKSDB})
@@ -524,7 +529,9 @@ endif()
 # on their origin (i.e. vendored source or packages on conda-forge).
 if(${ARCTICDB_USING_CONDA})
 
-    # We must use dynamic libraries.
+    # We must use dynamic libraries, except for xxHash, which must be statically linked.
+    # since `XXH_state_t` which we rely on is only available when statically linking.
+    # For all builds except linux conda's, we inline the functions so that xxhash does not need linking at all.
     list (APPEND arcticdb_core_libraries
         xxHash::xxHash
         pcre
@@ -538,10 +545,7 @@ if(${ARCTICDB_USING_CONDA})
     endif()
 else()
 
-    add_compile_definitions(ARCTICDB_USING_STATIC_XXHASH)
-
     list (APPEND arcticdb_core_libraries
-        xxhash_static
         unofficial::pcre::pcre
         msgpackc-cxx
         lmdb
diff --git a/cpp/arcticdb/util/hash.hpp b/cpp/arcticdb/util/hash.hpp
index d5af99d5bc..d80794ea48 100644
--- a/cpp/arcticdb/util/hash.hpp
+++ b/cpp/arcticdb/util/hash.hpp
@@ -10,20 +10,25 @@
 #include <cstdint>
 #include <string_view>
 
-// Adapt macro inlining depending on xxhash's linkage for the build.
-#ifdef ARCTICDB_USING_STATIC_XXHASH
+#include <folly/hash/Hash.h>
+
+// XXH_INLINE_ALL causes hashes to be non-deterministic with the linux conda build, needs investigating
+// https://github.com/man-group/ArcticDB/issues/1268
+#if defined(ARCTICDB_USING_CONDA) && defined(__linux__)
 #define XXH_STATIC_LINKING_ONLY
 #else
+// xxhash does some raw pointer manipulation that are safe, but compilers view as violating array bounds
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Warray-bounds"
 #define XXH_INLINE_ALL
-#endif 
+#endif
 #include <xxhash.h>
-#ifdef ARCTICDB_USING_STATIC_XXHASH
+#if defined(ARCTICDB_USING_CONDA) && defined(__linux__)
 #undef XXH_STATIC_LINKING_ONLY
 #else
 #undef XXH_INLINE_ALL
-#endif 
-
-#include <folly/hash/Hash.h>
+#pragma GCC diagnostic pop
+#endif
 
 namespace arcticdb {
 
@@ -31,10 +36,16 @@ using HashedValue = XXH64_hash_t;
 constexpr std::size_t DEFAULT_SEED = 0x42;
 
 template<class T, std::size_t seed = DEFAULT_SEED>
-HashedValue hash(T *d, std::size_t count = 1) {
+HashedValue hash(T *d, std::size_t count) {
     return XXH64(reinterpret_cast<const void *>(d), count * sizeof(T), seed);
 }
 
+// size argument to XXH64 being compile-time constant improves performance
+template<class T, std::size_t seed = DEFAULT_SEED>
+HashedValue hash(T *d) {
+    return XXH64(reinterpret_cast<const void *>(d), sizeof(T), seed);
+}
+
 inline HashedValue hash(std::string_view sv) {
     return hash(sv.data(), sv.size());
 }
diff --git a/cpp/third_party/CMakeLists.txt b/cpp/third_party/CMakeLists.txt
index e320c9e4d4..aaf5cc4e58 100644
--- a/cpp/third_party/CMakeLists.txt
+++ b/cpp/third_party/CMakeLists.txt
@@ -1,6 +1,5 @@
 if(NOT ${ARCTICDB_USING_CONDA})
     add_subdirectory(pybind11)
-    add_subdirectory(xxhash)
     add_subdirectory(recycle)
     add_subdirectory(semimap EXCLUDE_FROM_ALL)
     add_subdirectory(msgpack-c)
diff --git a/cpp/third_party/xxhash/CMakeLists.txt b/cpp/third_party/xxhash/CMakeLists.txt
deleted file mode 100644
index ea2e70fd69..0000000000
--- a/cpp/third_party/xxhash/CMakeLists.txt
+++ /dev/null
@@ -1,3 +0,0 @@
-add_library(xxhash_static STATIC xxhash.c)
-target_include_directories(xxhash_static PUBLIC $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}>)
-
diff --git a/cpp/third_party/xxhash/README.md b/cpp/third_party/xxhash/README.md
deleted file mode 100644
index cd94ed8cc5..0000000000
--- a/cpp/third_party/xxhash/README.md
+++ /dev/null
@@ -1,2 +0,0 @@
-Downloaded from https://github.com/Cyan4973/xxHash
-v0.6.5
\ No newline at end of file
diff --git a/cpp/third_party/xxhash/xxhash.c b/cpp/third_party/xxhash/xxhash.c
deleted file mode 100644
index da06ea72bf..0000000000
--- a/cpp/third_party/xxhash/xxhash.c
+++ /dev/null
@@ -1,1029 +0,0 @@
-/*
-*  xxHash - Fast Hash algorithm
-*  Copyright (C) 2012-2016, Yann Collet
-*
-*  BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
-*
-*  Redistribution and use in source and binary forms, with or without
-*  modification, are permitted provided that the following conditions are
-*  met:
-*
-*  * Redistributions of source code must retain the above copyright
-*  notice, this list of conditions and the following disclaimer.
-*  * Redistributions in binary form must reproduce the above
-*  copyright notice, this list of conditions and the following disclaimer
-*  in the documentation and/or other materials provided with the
-*  distribution.
-*
-*  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-*  "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-*  LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-*  A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-*  OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-*  SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-*  LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-*  DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-*  THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-*  (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-*  OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-*
-*  You can contact the author at :
-*  - xxHash homepage: http://www.xxhash.com
-*  - xxHash source repository : https://github.com/Cyan4973/xxHash
-*/
-
-
-/* *************************************
-*  Tuning parameters
-***************************************/
-/*!XXH_FORCE_MEMORY_ACCESS :
- * By default, access to unaligned memory is controlled by `memcpy()`, which is safe and portable.
- * Unfortunately, on some target/compiler combinations, the generated assembly is sub-optimal.
- * The below switch allow to select different access method for improved performance.
- * Method 0 (default) : use `memcpy()`. Safe and portable.
- * Method 1 : `__packed` statement. It depends on compiler extension (ie, not portable).
- *            This method is safe if your compiler supports it, and *generally* as fast or faster than `memcpy`.
- * Method 2 : direct access. This method doesn't depend on compiler but violate C standard.
- *            It can generate buggy code on targets which do not support unaligned memory accesses.
- *            But in some circumstances, it's the only known way to get the most performance (ie GCC + ARMv6)
- * See http://stackoverflow.com/a/32095106/646947 for details.
- * Prefer these methods in priority order (0 > 1 > 2)
- */
-#ifndef XXH_FORCE_MEMORY_ACCESS   /* can be defined externally, on command line for example */
-#  if defined(__GNUC__) && ( defined(__ARM_ARCH_6__) || defined(__ARM_ARCH_6J__) \
-                        || defined(__ARM_ARCH_6K__) || defined(__ARM_ARCH_6Z__) \
-                        || defined(__ARM_ARCH_6ZK__) || defined(__ARM_ARCH_6T2__) )
-#    define XXH_FORCE_MEMORY_ACCESS 2
-#  elif (defined(__INTEL_COMPILER) && !defined(_WIN32)) || \
-  (defined(__GNUC__) && ( defined(__ARM_ARCH_7__) || defined(__ARM_ARCH_7A__) \
-                    || defined(__ARM_ARCH_7R__) || defined(__ARM_ARCH_7M__) \
-                    || defined(__ARM_ARCH_7S__) ))
-#    define XXH_FORCE_MEMORY_ACCESS 1
-#  endif
-#endif
-
-/*!XXH_ACCEPT_NULL_INPUT_POINTER :
- * If input pointer is NULL, xxHash default behavior is to dereference it, triggering a segfault.
- * When this macro is enabled, xxHash actively checks input for null pointer.
- * It it is, result for null input pointers is the same as a null-length input.
- */
-#ifndef XXH_ACCEPT_NULL_INPUT_POINTER   /* can be defined externally */
-#  define XXH_ACCEPT_NULL_INPUT_POINTER 0
-#endif
-
-/*!XXH_FORCE_NATIVE_FORMAT :
- * By default, xxHash library provides endian-independent Hash values, based on little-endian convention.
- * Results are therefore identical for little-endian and big-endian CPU.
- * This comes at a performance cost for big-endian CPU, since some swapping is required to emulate little-endian format.
- * Should endian-independence be of no importance for your application, you may set the #define below to 1,
- * to improve speed for Big-endian CPU.
- * This option has no impact on Little_Endian CPU.
- */
-#ifndef XXH_FORCE_NATIVE_FORMAT   /* can be defined externally */
-#  define XXH_FORCE_NATIVE_FORMAT 0
-#endif
-
-/*!XXH_FORCE_ALIGN_CHECK :
- * This is a minor performance trick, only useful with lots of very small keys.
- * It means : check for aligned/unaligned input.
- * The check costs one initial branch per hash;
- * set it to 0 when the input is guaranteed to be aligned,
- * or when alignment doesn't matter for performance.
- */
-#ifndef XXH_FORCE_ALIGN_CHECK /* can be defined externally */
-#  if defined(__i386) || defined(_M_IX86) || defined(__x86_64__) || defined(_M_X64)
-#    define XXH_FORCE_ALIGN_CHECK 0
-#  else
-#    define XXH_FORCE_ALIGN_CHECK 1
-#  endif
-#endif
-
-
-/* *************************************
-*  Includes & Memory related functions
-***************************************/
-/*! Modify the local functions below should you wish to use some other memory routines
-*   for malloc(), free() */
-#include <stdlib.h>
-static void* XXH_malloc(size_t s) { return malloc(s); }
-static void  XXH_free  (void* p)  { free(p); }
-/*! and for memcpy() */
-#include <string.h>
-static void* XXH_memcpy(void* dest, const void* src, size_t size) { return memcpy(dest,src,size); }
-
-#include <assert.h>   /* assert */
-
-#define XXH_STATIC_LINKING_ONLY
-#include "xxhash.h"
-
-
-/* *************************************
-*  Compiler Specific Options
-***************************************/
-#ifdef _MSC_VER    /* Visual Studio */
-#  pragma warning(disable : 4127)      /* disable: C4127: conditional expression is constant */
-#  define FORCE_INLINE static __forceinline
-#else
-#  if defined (__cplusplus) || defined (__STDC_VERSION__) && __STDC_VERSION__ >= 199901L   /* C99 */
-#    ifdef __GNUC__
-#      define FORCE_INLINE static inline __attribute__((always_inline))
-#    else
-#      define FORCE_INLINE static inline
-#    endif
-#  else
-#    define FORCE_INLINE static
-#  endif /* __STDC_VERSION__ */
-#endif
-
-
-/* *************************************
-*  Basic Types
-***************************************/
-#ifndef MEM_MODULE
-# if !defined (__VMS) \
-  && (defined (__cplusplus) \
-  || (defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */) )
-#   include <stdint.h>
-    typedef uint8_t  BYTE;
-    typedef uint16_t U16;
-    typedef uint32_t U32;
-# else
-    typedef unsigned char      BYTE;
-    typedef unsigned short     U16;
-    typedef unsigned int       U32;
-# endif
-#endif
-
-#if (defined(XXH_FORCE_MEMORY_ACCESS) && (XXH_FORCE_MEMORY_ACCESS==2))
-
-/* Force direct memory access. Only works on CPU which support unaligned memory access in hardware */
-static U32 XXH_read32(const void* memPtr) { return *(const U32*) memPtr; }
-
-#elif (defined(XXH_FORCE_MEMORY_ACCESS) && (XXH_FORCE_MEMORY_ACCESS==1))
-
-/* __pack instructions are safer, but compiler specific, hence potentially problematic for some compilers */
-/* currently only defined for gcc and icc */
-typedef union { U32 u32; } __attribute__((packed)) unalign;
-static U32 XXH_read32(const void* ptr) { return ((const unalign*)ptr)->u32; }
-
-#else
-
-/* portable and safe solution. Generally efficient.
- * see : http://stackoverflow.com/a/32095106/646947
- */
-static U32 XXH_read32(const void* memPtr)
-{
-    U32 val;
-    memcpy(&val, memPtr, sizeof(val));
-    return val;
-}
-
-#endif   /* XXH_FORCE_DIRECT_MEMORY_ACCESS */
-
-
-/* ****************************************
-*  Compiler-specific Functions and Macros
-******************************************/
-#define XXH_GCC_VERSION (__GNUC__ * 100 + __GNUC_MINOR__)
-
-/* Note : although _rotl exists for minGW (GCC under windows), performance seems poor */
-#if defined(_MSC_VER)
-#  define XXH_rotl32(x,r) _rotl(x,r)
-#  define XXH_rotl64(x,r) _rotl64(x,r)
-#else
-#  define XXH_rotl32(x,r) ((x << r) | (x >> (32 - r)))
-#  define XXH_rotl64(x,r) ((x << r) | (x >> (64 - r)))
-#endif
-
-#if defined(_MSC_VER)     /* Visual Studio */
-#  define XXH_swap32 _byteswap_ulong
-#elif XXH_GCC_VERSION >= 403
-#  define XXH_swap32 __builtin_bswap32
-#else
-static U32 XXH_swap32 (U32 x)
-{
-    return  ((x << 24) & 0xff000000 ) |
-            ((x <<  8) & 0x00ff0000 ) |
-            ((x >>  8) & 0x0000ff00 ) |
-            ((x >> 24) & 0x000000ff );
-}
-#endif
-
-
-/* *************************************
-*  Architecture Macros
-***************************************/
-typedef enum { XXH_bigEndian=0, XXH_littleEndian=1 } XXH_endianess;
-
-/* XXH_CPU_LITTLE_ENDIAN can be defined externally, for example on the compiler command line */
-#ifndef XXH_CPU_LITTLE_ENDIAN
-static int XXH_isLittleEndian(void)
-{
-    const union { U32 u; BYTE c[4]; } one = { 1 };   /* don't use static : performance detrimental  */
-    return one.c[0];
-}
-#   define XXH_CPU_LITTLE_ENDIAN   XXH_isLittleEndian()
-#endif
-
-
-/* ***************************
-*  Memory reads
-*****************************/
-typedef enum { XXH_aligned, XXH_unaligned } XXH_alignment;
-
-FORCE_INLINE U32 XXH_readLE32_align(const void* ptr, XXH_endianess endian, XXH_alignment align)
-{
-    if (align==XXH_unaligned)
-        return endian==XXH_littleEndian ? XXH_read32(ptr) : XXH_swap32(XXH_read32(ptr));
-    else
-        return endian==XXH_littleEndian ? *(const U32*)ptr : XXH_swap32(*(const U32*)ptr);
-}
-
-FORCE_INLINE U32 XXH_readLE32(const void* ptr, XXH_endianess endian)
-{
-    return XXH_readLE32_align(ptr, endian, XXH_unaligned);
-}
-
-static U32 XXH_readBE32(const void* ptr)
-{
-    return XXH_CPU_LITTLE_ENDIAN ? XXH_swap32(XXH_read32(ptr)) : XXH_read32(ptr);
-}
-
-
-/* *************************************
-*  Macros
-***************************************/
-#define XXH_STATIC_ASSERT(c)  { enum { XXH_sa = 1/(int)(!!(c)) }; }  /* use after variable declarations */
-XXH_PUBLIC_API unsigned XXH_versionNumber (void) { return XXH_VERSION_NUMBER; }
-
-
-/* *******************************************************************
-*  32-bit hash functions
-*********************************************************************/
-static const U32 PRIME32_1 = 2654435761U;
-static const U32 PRIME32_2 = 2246822519U;
-static const U32 PRIME32_3 = 3266489917U;
-static const U32 PRIME32_4 =  668265263U;
-static const U32 PRIME32_5 =  374761393U;
-
-static U32 XXH32_round(U32 seed, U32 input)
-{
-    seed += input * PRIME32_2;
-    seed  = XXH_rotl32(seed, 13);
-    seed *= PRIME32_1;
-    return seed;
-}
-
-/* mix all bits */
-static U32 XXH32_avalanche(U32 h32)
-{
-    h32 ^= h32 >> 15;
-    h32 *= PRIME32_2;
-    h32 ^= h32 >> 13;
-    h32 *= PRIME32_3;
-    h32 ^= h32 >> 16;
-    return(h32);
-}
-
-#define XXH_get32bits(p) XXH_readLE32_align(p, endian, align)
-
-static U32
-XXH32_finalize(U32 h32, const void* ptr, size_t len,
-                XXH_endianess endian, XXH_alignment align)
-
-{
-    const BYTE* p = (const BYTE*)ptr;
-#define PROCESS1             \
-    h32 += (*p) * PRIME32_5; \
-    p++;                     \
-    h32 = XXH_rotl32(h32, 11) * PRIME32_1 ;
-
-#define PROCESS4                         \
-    h32 += XXH_get32bits(p) * PRIME32_3; \
-    p+=4;                                \
-    h32  = XXH_rotl32(h32, 17) * PRIME32_4 ;
-
-    switch(len&15)  /* or switch(bEnd - p) */
-    {
-      case 12:      PROCESS4;
-                    /* fallthrough */
-      case 8:       PROCESS4;
-                    /* fallthrough */
-      case 4:       PROCESS4;
-                    return XXH32_avalanche(h32);
-
-      case 13:      PROCESS4;
-                    /* fallthrough */
-      case 9:       PROCESS4;
-                    /* fallthrough */
-      case 5:       PROCESS4;
-                    PROCESS1;
-                    return XXH32_avalanche(h32);
-
-      case 14:      PROCESS4;
-                    /* fallthrough */
-      case 10:      PROCESS4;
-                    /* fallthrough */
-      case 6:       PROCESS4;
-                    PROCESS1;
-                    PROCESS1;
-                    return XXH32_avalanche(h32);
-
-      case 15:      PROCESS4;
-                    /* fallthrough */
-      case 11:      PROCESS4;
-                    /* fallthrough */
-      case 7:       PROCESS4;
-                    /* fallthrough */
-      case 3:       PROCESS1;
-                    /* fallthrough */
-      case 2:       PROCESS1;
-                    /* fallthrough */
-      case 1:       PROCESS1;
-                    /* fallthrough */
-      case 0:       return XXH32_avalanche(h32);
-    }
-    assert(0);
-    return h32;   /* reaching this point is deemed impossible */
-}
-
-
-FORCE_INLINE U32
-XXH32_endian_align(const void* input, size_t len, U32 seed,
-                    XXH_endianess endian, XXH_alignment align)
-{
-    const BYTE* p = (const BYTE*)input;
-    const BYTE* bEnd = p + len;
-    U32 h32;
-
-#if defined(XXH_ACCEPT_NULL_INPUT_POINTER) && (XXH_ACCEPT_NULL_INPUT_POINTER>=1)
-    if (p==NULL) {
-        len=0;
-        bEnd=p=(const BYTE*)(size_t)16;
-    }
-#endif
-
-    if (len>=16) {
-        const BYTE* const limit = bEnd - 15;
-        U32 v1 = seed + PRIME32_1 + PRIME32_2;
-        U32 v2 = seed + PRIME32_2;
-        U32 v3 = seed + 0;
-        U32 v4 = seed - PRIME32_1;
-
-        do {
-            v1 = XXH32_round(v1, XXH_get32bits(p)); p+=4;
-            v2 = XXH32_round(v2, XXH_get32bits(p)); p+=4;
-            v3 = XXH32_round(v3, XXH_get32bits(p)); p+=4;
-            v4 = XXH32_round(v4, XXH_get32bits(p)); p+=4;
-        } while (p < limit);
-
-        h32 = XXH_rotl32(v1, 1)  + XXH_rotl32(v2, 7)
-            + XXH_rotl32(v3, 12) + XXH_rotl32(v4, 18);
-    } else {
-        h32  = seed + PRIME32_5;
-    }
-
-    h32 += (U32)len;
-
-    return XXH32_finalize(h32, p, len&15, endian, align);
-}
-
-
-XXH_PUBLIC_API unsigned int XXH32 (const void* input, size_t len, unsigned int seed)
-{
-#if 0
-    /* Simple version, good for code maintenance, but unfortunately slow for small inputs */
-    XXH32_state_t state;
-    XXH32_reset(&state, seed);
-    XXH32_update(&state, input, len);
-    return XXH32_digest(&state);
-#else
-    XXH_endianess endian_detected = (XXH_endianess)XXH_CPU_LITTLE_ENDIAN;
-
-    if (XXH_FORCE_ALIGN_CHECK) {
-        if ((((size_t)input) & 3) == 0) {   /* Input is 4-bytes aligned, leverage the speed benefit */
-            if ((endian_detected==XXH_littleEndian) || XXH_FORCE_NATIVE_FORMAT)
-                return XXH32_endian_align(input, len, seed, XXH_littleEndian, XXH_aligned);
-            else
-                return XXH32_endian_align(input, len, seed, XXH_bigEndian, XXH_aligned);
-    }   }
-
-    if ((endian_detected==XXH_littleEndian) || XXH_FORCE_NATIVE_FORMAT)
-        return XXH32_endian_align(input, len, seed, XXH_littleEndian, XXH_unaligned);
-    else
-        return XXH32_endian_align(input, len, seed, XXH_bigEndian, XXH_unaligned);
-#endif
-}
-
-
-
-/*======   Hash streaming   ======*/
-
-XXH_PUBLIC_API XXH32_state_t* XXH32_createState(void)
-{
-    return (XXH32_state_t*)XXH_malloc(sizeof(XXH32_state_t));
-}
-XXH_PUBLIC_API XXH_errorcode XXH32_freeState(XXH32_state_t* statePtr)
-{
-    XXH_free(statePtr);
-    return XXH_OK;
-}
-
-XXH_PUBLIC_API void XXH32_copyState(XXH32_state_t* dstState, const XXH32_state_t* srcState)
-{
-    memcpy(dstState, srcState, sizeof(*dstState));
-}
-
-XXH_PUBLIC_API XXH_errorcode XXH32_reset(XXH32_state_t* statePtr, unsigned int seed)
-{
-    XXH32_state_t state;   /* using a local state to memcpy() in order to avoid strict-aliasing warnings */
-    memset(&state, 0, sizeof(state));
-    state.v1 = seed + PRIME32_1 + PRIME32_2;
-    state.v2 = seed + PRIME32_2;
-    state.v3 = seed + 0;
-    state.v4 = seed - PRIME32_1;
-    /* do not write into reserved, planned to be removed in a future version */
-    memcpy(statePtr, &state, sizeof(state) - sizeof(state.reserved));
-    return XXH_OK;
-}
-
-
-FORCE_INLINE
-XXH_errorcode XXH32_update_endian (XXH32_state_t* state, const void* input, size_t len, XXH_endianess endian)
-{
-    const BYTE* p = (const BYTE*)input;
-    const BYTE* const bEnd = p + len;
-
-    if (input==NULL)
-#if defined(XXH_ACCEPT_NULL_INPUT_POINTER) && (XXH_ACCEPT_NULL_INPUT_POINTER>=1)
-        return XXH_OK;
-#else
-        return XXH_ERROR;
-#endif
-
-    state->total_len_32 += (unsigned)len;
-    state->large_len |= (len>=16) | (state->total_len_32>=16);
-
-    if (state->memsize + len < 16)  {   /* fill in tmp buffer */
-        XXH_memcpy((BYTE*)(state->mem32) + state->memsize, input, len);
-        state->memsize += (unsigned)len;
-        return XXH_OK;
-    }
-
-    if (state->memsize) {   /* some data left from previous update */
-        XXH_memcpy((BYTE*)(state->mem32) + state->memsize, input, 16-state->memsize);
-        {   const U32* p32 = state->mem32;
-            state->v1 = XXH32_round(state->v1, XXH_readLE32(p32, endian)); p32++;
-            state->v2 = XXH32_round(state->v2, XXH_readLE32(p32, endian)); p32++;
-            state->v3 = XXH32_round(state->v3, XXH_readLE32(p32, endian)); p32++;
-            state->v4 = XXH32_round(state->v4, XXH_readLE32(p32, endian));
-        }
-        p += 16-state->memsize;
-        state->memsize = 0;
-    }
-
-    if (p <= bEnd-16) {
-        const BYTE* const limit = bEnd - 16;
-        U32 v1 = state->v1;
-        U32 v2 = state->v2;
-        U32 v3 = state->v3;
-        U32 v4 = state->v4;
-
-        do {
-            v1 = XXH32_round(v1, XXH_readLE32(p, endian)); p+=4;
-            v2 = XXH32_round(v2, XXH_readLE32(p, endian)); p+=4;
-            v3 = XXH32_round(v3, XXH_readLE32(p, endian)); p+=4;
-            v4 = XXH32_round(v4, XXH_readLE32(p, endian)); p+=4;
-        } while (p<=limit);
-
-        state->v1 = v1;
-        state->v2 = v2;
-        state->v3 = v3;
-        state->v4 = v4;
-    }
-
-    if (p < bEnd) {
-        XXH_memcpy(state->mem32, p, (size_t)(bEnd-p));
-        state->memsize = (unsigned)(bEnd-p);
-    }
-
-    return XXH_OK;
-}
-
-
-XXH_PUBLIC_API XXH_errorcode XXH32_update (XXH32_state_t* state_in, const void* input, size_t len)
-{
-    XXH_endianess endian_detected = (XXH_endianess)XXH_CPU_LITTLE_ENDIAN;
-
-    if ((endian_detected==XXH_littleEndian) || XXH_FORCE_NATIVE_FORMAT)
-        return XXH32_update_endian(state_in, input, len, XXH_littleEndian);
-    else
-        return XXH32_update_endian(state_in, input, len, XXH_bigEndian);
-}
-
-
-FORCE_INLINE U32
-XXH32_digest_endian (const XXH32_state_t* state, XXH_endianess endian)
-{
-    U32 h32;
-
-    if (state->large_len) {
-        h32 = XXH_rotl32(state->v1, 1)
-            + XXH_rotl32(state->v2, 7)
-            + XXH_rotl32(state->v3, 12)
-            + XXH_rotl32(state->v4, 18);
-    } else {
-        h32 = state->v3 /* == seed */ + PRIME32_5;
-    }
-
-    h32 += state->total_len_32;
-
-    return XXH32_finalize(h32, state->mem32, state->memsize, endian, XXH_aligned);
-}
-
-
-XXH_PUBLIC_API unsigned int XXH32_digest (const XXH32_state_t* state_in)
-{
-    XXH_endianess endian_detected = (XXH_endianess)XXH_CPU_LITTLE_ENDIAN;
-
-    if ((endian_detected==XXH_littleEndian) || XXH_FORCE_NATIVE_FORMAT)
-        return XXH32_digest_endian(state_in, XXH_littleEndian);
-    else
-        return XXH32_digest_endian(state_in, XXH_bigEndian);
-}
-
-
-/*======   Canonical representation   ======*/
-
-/*! Default XXH result types are basic unsigned 32 and 64 bits.
-*   The canonical representation follows human-readable write convention, aka big-endian (large digits first).
-*   These functions allow transformation of hash result into and from its canonical format.
-*   This way, hash values can be written into a file or buffer, remaining comparable across different systems.
-*/
-
-XXH_PUBLIC_API void XXH32_canonicalFromHash(XXH32_canonical_t* dst, XXH32_hash_t hash)
-{
-    XXH_STATIC_ASSERT(sizeof(XXH32_canonical_t) == sizeof(XXH32_hash_t));
-    if (XXH_CPU_LITTLE_ENDIAN) hash = XXH_swap32(hash);
-    memcpy(dst, &hash, sizeof(*dst));
-}
-
-XXH_PUBLIC_API XXH32_hash_t XXH32_hashFromCanonical(const XXH32_canonical_t* src)
-{
-    return XXH_readBE32(src);
-}
-
-
-#ifndef XXH_NO_LONG_LONG
-
-/* *******************************************************************
-*  64-bit hash functions
-*********************************************************************/
-
-/*======   Memory access   ======*/
-
-#ifndef MEM_MODULE
-# define MEM_MODULE
-# if !defined (__VMS) \
-  && (defined (__cplusplus) \
-  || (defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */) )
-#   include <stdint.h>
-    typedef uint64_t U64;
-# else
-    /* if compiler doesn't support unsigned long long, replace by another 64-bit type */
-    typedef unsigned long long U64;
-# endif
-#endif
-
-
-#if (defined(XXH_FORCE_MEMORY_ACCESS) && (XXH_FORCE_MEMORY_ACCESS==2))
-
-/* Force direct memory access. Only works on CPU which support unaligned memory access in hardware */
-static U64 XXH_read64(const void* memPtr) { return *(const U64*) memPtr; }
-
-#elif (defined(XXH_FORCE_MEMORY_ACCESS) && (XXH_FORCE_MEMORY_ACCESS==1))
-
-/* __pack instructions are safer, but compiler specific, hence potentially problematic for some compilers */
-/* currently only defined for gcc and icc */
-typedef union { U32 u32; U64 u64; } __attribute__((packed)) unalign64;
-static U64 XXH_read64(const void* ptr) { return ((const unalign64*)ptr)->u64; }
-
-#else
-
-/* portable and safe solution. Generally efficient.
- * see : http://stackoverflow.com/a/32095106/646947
- */
-
-static U64 XXH_read64(const void* memPtr)
-{
-    U64 val;
-    memcpy(&val, memPtr, sizeof(val));
-    return val;
-}
-
-#endif   /* XXH_FORCE_DIRECT_MEMORY_ACCESS */
-
-#if defined(_MSC_VER)     /* Visual Studio */
-#  define XXH_swap64 _byteswap_uint64
-#elif XXH_GCC_VERSION >= 403
-#  define XXH_swap64 __builtin_bswap64
-#else
-static U64 XXH_swap64 (U64 x)
-{
-    return  ((x << 56) & 0xff00000000000000ULL) |
-            ((x << 40) & 0x00ff000000000000ULL) |
-            ((x << 24) & 0x0000ff0000000000ULL) |
-            ((x << 8)  & 0x000000ff00000000ULL) |
-            ((x >> 8)  & 0x00000000ff000000ULL) |
-            ((x >> 24) & 0x0000000000ff0000ULL) |
-            ((x >> 40) & 0x000000000000ff00ULL) |
-            ((x >> 56) & 0x00000000000000ffULL);
-}
-#endif
-
-FORCE_INLINE U64 XXH_readLE64_align(const void* ptr, XXH_endianess endian, XXH_alignment align)
-{
-    if (align==XXH_unaligned)
-        return endian==XXH_littleEndian ? XXH_read64(ptr) : XXH_swap64(XXH_read64(ptr));
-    else
-        return endian==XXH_littleEndian ? *(const U64*)ptr : XXH_swap64(*(const U64*)ptr);
-}
-
-FORCE_INLINE U64 XXH_readLE64(const void* ptr, XXH_endianess endian)
-{
-    return XXH_readLE64_align(ptr, endian, XXH_unaligned);
-}
-
-static U64 XXH_readBE64(const void* ptr)
-{
-    return XXH_CPU_LITTLE_ENDIAN ? XXH_swap64(XXH_read64(ptr)) : XXH_read64(ptr);
-}
-
-
-/*======   xxh64   ======*/
-
-static const U64 PRIME64_1 = 11400714785074694791ULL;
-static const U64 PRIME64_2 = 14029467366897019727ULL;
-static const U64 PRIME64_3 =  1609587929392839161ULL;
-static const U64 PRIME64_4 =  9650029242287828579ULL;
-static const U64 PRIME64_5 =  2870177450012600261ULL;
-
-static U64 XXH64_round(U64 acc, U64 input)
-{
-    acc += input * PRIME64_2;
-    acc  = XXH_rotl64(acc, 31);
-    acc *= PRIME64_1;
-    return acc;
-}
-
-static U64 XXH64_mergeRound(U64 acc, U64 val)
-{
-    val  = XXH64_round(0, val);
-    acc ^= val;
-    acc  = acc * PRIME64_1 + PRIME64_4;
-    return acc;
-}
-
-static U64 XXH64_avalanche(U64 h64)
-{
-    h64 ^= h64 >> 33;
-    h64 *= PRIME64_2;
-    h64 ^= h64 >> 29;
-    h64 *= PRIME64_3;
-    h64 ^= h64 >> 32;
-    return h64;
-}
-
-
-#define XXH_get64bits(p) XXH_readLE64_align(p, endian, align)
-
-static U64
-XXH64_finalize(U64 h64, const void* ptr, size_t len,
-               XXH_endianess endian, XXH_alignment align)
-{
-    const BYTE* p = (const BYTE*)ptr;
-
-#define PROCESS1_64          \
-    h64 ^= (*p) * PRIME64_5; \
-    p++;                     \
-    h64 = XXH_rotl64(h64, 11) * PRIME64_1;
-
-#define PROCESS4_64          \
-    h64 ^= (U64)(XXH_get32bits(p)) * PRIME64_1; \
-    p+=4;                    \
-    h64 = XXH_rotl64(h64, 23) * PRIME64_2 + PRIME64_3;
-
-#define PROCESS8_64 {        \
-    U64 const k1 = XXH64_round(0, XXH_get64bits(p)); \
-    p+=8;                    \
-    h64 ^= k1;               \
-    h64  = XXH_rotl64(h64,27) * PRIME64_1 + PRIME64_4; \
-}
-
-    switch(len&31) {
-      case 24: PROCESS8_64;
-                    /* fallthrough */
-      case 16: PROCESS8_64;
-                    /* fallthrough */
-      case  8: PROCESS8_64;
-               return XXH64_avalanche(h64);
-
-      case 28: PROCESS8_64;
-                    /* fallthrough */
-      case 20: PROCESS8_64;
-                    /* fallthrough */
-      case 12: PROCESS8_64;
-                    /* fallthrough */
-      case  4: PROCESS4_64;
-               return XXH64_avalanche(h64);
-
-      case 25: PROCESS8_64;
-                    /* fallthrough */
-      case 17: PROCESS8_64;
-                    /* fallthrough */
-      case  9: PROCESS8_64;
-               PROCESS1_64;
-               return XXH64_avalanche(h64);
-
-      case 29: PROCESS8_64;
-                    /* fallthrough */
-      case 21: PROCESS8_64;
-                    /* fallthrough */
-      case 13: PROCESS8_64;
-                    /* fallthrough */
-      case  5: PROCESS4_64;
-               PROCESS1_64;
-               return XXH64_avalanche(h64);
-
-      case 26: PROCESS8_64;
-                    /* fallthrough */
-      case 18: PROCESS8_64;
-                    /* fallthrough */
-      case 10: PROCESS8_64;
-               PROCESS1_64;
-               PROCESS1_64;
-               return XXH64_avalanche(h64);
-
-      case 30: PROCESS8_64;
-                    /* fallthrough */
-      case 22: PROCESS8_64;
-                    /* fallthrough */
-      case 14: PROCESS8_64;
-                    /* fallthrough */
-      case  6: PROCESS4_64;
-               PROCESS1_64;
-               PROCESS1_64;
-               return XXH64_avalanche(h64);
-
-      case 27: PROCESS8_64;
-                    /* fallthrough */
-      case 19: PROCESS8_64;
-                    /* fallthrough */
-      case 11: PROCESS8_64;
-               PROCESS1_64;
-               PROCESS1_64;
-               PROCESS1_64;
-               return XXH64_avalanche(h64);
-
-      case 31: PROCESS8_64;
-                    /* fallthrough */
-      case 23: PROCESS8_64;
-                    /* fallthrough */
-      case 15: PROCESS8_64;
-                    /* fallthrough */
-      case  7: PROCESS4_64;
-                    /* fallthrough */
-      case  3: PROCESS1_64;
-                    /* fallthrough */
-      case  2: PROCESS1_64;
-                    /* fallthrough */
-      case  1: PROCESS1_64;
-                    /* fallthrough */
-      case  0: return XXH64_avalanche(h64);
-    }
-
-    /* impossible to reach */
-    assert(0);
-    return 0;  /* unreachable, but some compilers complain without it */
-}
-
-FORCE_INLINE U64
-XXH64_endian_align(const void* input, size_t len, U64 seed,
-                XXH_endianess endian, XXH_alignment align)
-{
-    const BYTE* p = (const BYTE*)input;
-    const BYTE* bEnd = p + len;
-    U64 h64;
-
-#if defined(XXH_ACCEPT_NULL_INPUT_POINTER) && (XXH_ACCEPT_NULL_INPUT_POINTER>=1)
-    if (p==NULL) {
-        len=0;
-        bEnd=p=(const BYTE*)(size_t)32;
-    }
-#endif
-
-    if (len>=32) {
-        const BYTE* const limit = bEnd - 32;
-        U64 v1 = seed + PRIME64_1 + PRIME64_2;
-        U64 v2 = seed + PRIME64_2;
-        U64 v3 = seed + 0;
-        U64 v4 = seed - PRIME64_1;
-
-        do {
-            v1 = XXH64_round(v1, XXH_get64bits(p)); p+=8;
-            v2 = XXH64_round(v2, XXH_get64bits(p)); p+=8;
-            v3 = XXH64_round(v3, XXH_get64bits(p)); p+=8;
-            v4 = XXH64_round(v4, XXH_get64bits(p)); p+=8;
-        } while (p<=limit);
-
-        h64 = XXH_rotl64(v1, 1) + XXH_rotl64(v2, 7) + XXH_rotl64(v3, 12) + XXH_rotl64(v4, 18);
-        h64 = XXH64_mergeRound(h64, v1);
-        h64 = XXH64_mergeRound(h64, v2);
-        h64 = XXH64_mergeRound(h64, v3);
-        h64 = XXH64_mergeRound(h64, v4);
-
-    } else {
-        h64  = seed + PRIME64_5;
-    }
-
-    h64 += (U64) len;
-
-    return XXH64_finalize(h64, p, len, endian, align);
-}
-
-
-XXH_PUBLIC_API unsigned long long XXH64 (const void* input, size_t len, unsigned long long seed)
-{
-#if 0
-    /* Simple version, good for code maintenance, but unfortunately slow for small inputs */
-    XXH64_state_t state;
-    XXH64_reset(&state, seed);
-    XXH64_update(&state, input, len);
-    return XXH64_digest(&state);
-#else
-    XXH_endianess endian_detected = (XXH_endianess)XXH_CPU_LITTLE_ENDIAN;
-
-    if (XXH_FORCE_ALIGN_CHECK) {
-        if ((((size_t)input) & 7)==0) {  /* Input is aligned, let's leverage the speed advantage */
-            if ((endian_detected==XXH_littleEndian) || XXH_FORCE_NATIVE_FORMAT)
-                return XXH64_endian_align(input, len, seed, XXH_littleEndian, XXH_aligned);
-            else
-                return XXH64_endian_align(input, len, seed, XXH_bigEndian, XXH_aligned);
-    }   }
-
-    if ((endian_detected==XXH_littleEndian) || XXH_FORCE_NATIVE_FORMAT)
-        return XXH64_endian_align(input, len, seed, XXH_littleEndian, XXH_unaligned);
-    else
-        return XXH64_endian_align(input, len, seed, XXH_bigEndian, XXH_unaligned);
-#endif
-}
-
-/*======   Hash Streaming   ======*/
-
-XXH_PUBLIC_API XXH64_state_t* XXH64_createState(void)
-{
-    return (XXH64_state_t*)XXH_malloc(sizeof(XXH64_state_t));
-}
-XXH_PUBLIC_API XXH_errorcode XXH64_freeState(XXH64_state_t* statePtr)
-{
-    XXH_free(statePtr);
-    return XXH_OK;
-}
-
-XXH_PUBLIC_API void XXH64_copyState(XXH64_state_t* dstState, const XXH64_state_t* srcState)
-{
-    memcpy(dstState, srcState, sizeof(*dstState));
-}
-
-XXH_PUBLIC_API XXH_errorcode XXH64_reset(XXH64_state_t* statePtr, unsigned long long seed)
-{
-    XXH64_state_t state;   /* using a local state to memcpy() in order to avoid strict-aliasing warnings */
-    memset(&state, 0, sizeof(state));
-    state.v1 = seed + PRIME64_1 + PRIME64_2;
-    state.v2 = seed + PRIME64_2;
-    state.v3 = seed + 0;
-    state.v4 = seed - PRIME64_1;
-     /* do not write into reserved, planned to be removed in a future version */
-    memcpy(statePtr, &state, sizeof(state) - sizeof(state.reserved));
-    return XXH_OK;
-}
-
-FORCE_INLINE
-XXH_errorcode XXH64_update_endian (XXH64_state_t* state, const void* input, size_t len, XXH_endianess endian)
-{
-    const BYTE* p = (const BYTE*)input;
-    const BYTE* const bEnd = p + len;
-
-    if (input==NULL)
-#if defined(XXH_ACCEPT_NULL_INPUT_POINTER) && (XXH_ACCEPT_NULL_INPUT_POINTER>=1)
-        return XXH_OK;
-#else
-        return XXH_ERROR;
-#endif
-
-    state->total_len += len;
-
-    if (state->memsize + len < 32) {  /* fill in tmp buffer */
-        XXH_memcpy(((BYTE*)state->mem64) + state->memsize, input, len);
-        state->memsize += (U32)len;
-        return XXH_OK;
-    }
-
-    if (state->memsize) {   /* tmp buffer is full */
-        XXH_memcpy(((BYTE*)state->mem64) + state->memsize, input, 32-state->memsize);
-        state->v1 = XXH64_round(state->v1, XXH_readLE64(state->mem64+0, endian));
-        state->v2 = XXH64_round(state->v2, XXH_readLE64(state->mem64+1, endian));
-        state->v3 = XXH64_round(state->v3, XXH_readLE64(state->mem64+2, endian));
-        state->v4 = XXH64_round(state->v4, XXH_readLE64(state->mem64+3, endian));
-        p += 32-state->memsize;
-        state->memsize = 0;
-    }
-
-    if (p+32 <= bEnd) {
-        const BYTE* const limit = bEnd - 32;
-        U64 v1 = state->v1;
-        U64 v2 = state->v2;
-        U64 v3 = state->v3;
-        U64 v4 = state->v4;
-
-        do {
-            v1 = XXH64_round(v1, XXH_readLE64(p, endian)); p+=8;
-            v2 = XXH64_round(v2, XXH_readLE64(p, endian)); p+=8;
-            v3 = XXH64_round(v3, XXH_readLE64(p, endian)); p+=8;
-            v4 = XXH64_round(v4, XXH_readLE64(p, endian)); p+=8;
-        } while (p<=limit);
-
-        state->v1 = v1;
-        state->v2 = v2;
-        state->v3 = v3;
-        state->v4 = v4;
-    }
-
-    if (p < bEnd) {
-        XXH_memcpy(state->mem64, p, (size_t)(bEnd-p));
-        state->memsize = (unsigned)(bEnd-p);
-    }
-
-    return XXH_OK;
-}
-
-XXH_PUBLIC_API XXH_errorcode XXH64_update (XXH64_state_t* state_in, const void* input, size_t len)
-{
-    XXH_endianess endian_detected = (XXH_endianess)XXH_CPU_LITTLE_ENDIAN;
-
-    if ((endian_detected==XXH_littleEndian) || XXH_FORCE_NATIVE_FORMAT)
-        return XXH64_update_endian(state_in, input, len, XXH_littleEndian);
-    else
-        return XXH64_update_endian(state_in, input, len, XXH_bigEndian);
-}
-
-FORCE_INLINE U64 XXH64_digest_endian (const XXH64_state_t* state, XXH_endianess endian)
-{
-    U64 h64;
-
-    if (state->total_len >= 32) {
-        U64 const v1 = state->v1;
-        U64 const v2 = state->v2;
-        U64 const v3 = state->v3;
-        U64 const v4 = state->v4;
-
-        h64 = XXH_rotl64(v1, 1) + XXH_rotl64(v2, 7) + XXH_rotl64(v3, 12) + XXH_rotl64(v4, 18);
-        h64 = XXH64_mergeRound(h64, v1);
-        h64 = XXH64_mergeRound(h64, v2);
-        h64 = XXH64_mergeRound(h64, v3);
-        h64 = XXH64_mergeRound(h64, v4);
-    } else {
-        h64  = state->v3 /*seed*/ + PRIME64_5;
-    }
-
-    h64 += (U64) state->total_len;
-
-    return XXH64_finalize(h64, state->mem64, (size_t)state->total_len, endian, XXH_aligned);
-}
-
-XXH_PUBLIC_API unsigned long long XXH64_digest (const XXH64_state_t* state_in)
-{
-    XXH_endianess endian_detected = (XXH_endianess)XXH_CPU_LITTLE_ENDIAN;
-
-    if ((endian_detected==XXH_littleEndian) || XXH_FORCE_NATIVE_FORMAT)
-        return XXH64_digest_endian(state_in, XXH_littleEndian);
-    else
-        return XXH64_digest_endian(state_in, XXH_bigEndian);
-}
-
-
-/*====== Canonical representation   ======*/
-
-XXH_PUBLIC_API void XXH64_canonicalFromHash(XXH64_canonical_t* dst, XXH64_hash_t hash)
-{
-    XXH_STATIC_ASSERT(sizeof(XXH64_canonical_t) == sizeof(XXH64_hash_t));
-    if (XXH_CPU_LITTLE_ENDIAN) hash = XXH_swap64(hash);
-    memcpy(dst, &hash, sizeof(*dst));
-}
-
-XXH_PUBLIC_API XXH64_hash_t XXH64_hashFromCanonical(const XXH64_canonical_t* src)
-{
-    return XXH_readBE64(src);
-}
-
-#endif  /* XXH_NO_LONG_LONG */
diff --git a/cpp/third_party/xxhash/xxhash.h b/cpp/third_party/xxhash/xxhash.h
deleted file mode 100644
index d6bad94335..0000000000
--- a/cpp/third_party/xxhash/xxhash.h
+++ /dev/null
@@ -1,328 +0,0 @@
-/*
-   xxHash - Extremely Fast Hash algorithm
-   Header File
-   Copyright (C) 2012-2016, Yann Collet.
-
-   BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
-
-   Redistribution and use in source and binary forms, with or without
-   modification, are permitted provided that the following conditions are
-   met:
-
-       * Redistributions of source code must retain the above copyright
-   notice, this list of conditions and the following disclaimer.
-       * Redistributions in binary form must reproduce the above
-   copyright notice, this list of conditions and the following disclaimer
-   in the documentation and/or other materials provided with the
-   distribution.
-
-   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-
-   You can contact the author at :
-   - xxHash source repository : https://github.com/Cyan4973/xxHash
-*/
-
-/* Notice extracted from xxHash homepage :
-
-xxHash is an extremely fast Hash algorithm, running at RAM speed limits.
-It also successfully passes all tests from the SMHasher suite.
-
-Comparison (single thread, Windows Seven 32 bits, using SMHasher on a Core 2 Duo @3GHz)
-
-Name            Speed       Q.Score   Author
-xxHash          5.4 GB/s     10
-CrapWow         3.2 GB/s      2       Andrew
-MumurHash 3a    2.7 GB/s     10       Austin Appleby
-SpookyHash      2.0 GB/s     10       Bob Jenkins
-SBox            1.4 GB/s      9       Bret Mulvey
-Lookup3         1.2 GB/s      9       Bob Jenkins
-SuperFastHash   1.2 GB/s      1       Paul Hsieh
-CityHash64      1.05 GB/s    10       Pike & Alakuijala
-FNV             0.55 GB/s     5       Fowler, Noll, Vo
-CRC32           0.43 GB/s     9
-MD5-32          0.33 GB/s    10       Ronald L. Rivest
-SHA1-32         0.28 GB/s    10
-
-Q.Score is a measure of quality of the hash function.
-It depends on successfully passing SMHasher test set.
-10 is a perfect score.
-
-A 64-bit version, named XXH64, is available since r35.
-It offers much better speed, but for 64-bit applications only.
-Name     Speed on 64 bits    Speed on 32 bits
-XXH64       13.8 GB/s            1.9 GB/s
-XXH32        6.8 GB/s            6.0 GB/s
-*/
-
-#ifndef XXHASH_H_5627135585666179
-#define XXHASH_H_5627135585666179 1
-
-#if defined (__cplusplus)
-extern "C" {
-#endif
-
-
-/* ****************************
-*  Definitions
-******************************/
-#include <stddef.h>   /* size_t */
-typedef enum { XXH_OK=0, XXH_ERROR } XXH_errorcode;
-
-
-/* ****************************
- *  API modifier
- ******************************/
-/** XXH_INLINE_ALL (and XXH_PRIVATE_API)
- *  This is useful to include xxhash functions in `static` mode
- *  in order to inline them, and remove their symbol from the public list.
- *  Inlining can offer dramatic performance improvement on small keys.
- *  Methodology :
- *     #define XXH_INLINE_ALL
- *     #include "xxhash.h"
- * `xxhash.c` is automatically included.
- *  It's not useful to compile and link it as a separate module.
- */
-#if defined(XXH_INLINE_ALL) || defined(XXH_PRIVATE_API)
-#  ifndef XXH_STATIC_LINKING_ONLY
-#    define XXH_STATIC_LINKING_ONLY
-#  endif
-#  if defined(__GNUC__)
-#    define XXH_PUBLIC_API static __inline __attribute__((unused))
-#  elif defined (__cplusplus) || (defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */)
-#    define XXH_PUBLIC_API static inline
-#  elif defined(_MSC_VER)
-#    define XXH_PUBLIC_API static __inline
-#  else
-     /* this version may generate warnings for unused static functions */
-#    define XXH_PUBLIC_API static
-#  endif
-#else
-#  define XXH_PUBLIC_API   /* do nothing */
-#endif /* XXH_INLINE_ALL || XXH_PRIVATE_API */
-
-/*! XXH_NAMESPACE, aka Namespace Emulation :
- *
- * If you want to include _and expose_ xxHash functions from within your own library,
- * but also want to avoid symbol collisions with other libraries which may also include xxHash,
- *
- * you can use XXH_NAMESPACE, to automatically prefix any public symbol from xxhash library
- * with the value of XXH_NAMESPACE (therefore, avoid NULL and numeric values).
- *
- * Note that no change is required within the calling program as long as it includes `xxhash.h` :
- * regular symbol name will be automatically translated by this header.
- */
-#ifdef XXH_NAMESPACE
-#  define XXH_CAT(A,B) A##B
-#  define XXH_NAME2(A,B) XXH_CAT(A,B)
-#  define XXH_versionNumber XXH_NAME2(XXH_NAMESPACE, XXH_versionNumber)
-#  define XXH32 XXH_NAME2(XXH_NAMESPACE, XXH32)
-#  define XXH32_createState XXH_NAME2(XXH_NAMESPACE, XXH32_createState)
-#  define XXH32_freeState XXH_NAME2(XXH_NAMESPACE, XXH32_freeState)
-#  define XXH32_reset XXH_NAME2(XXH_NAMESPACE, XXH32_reset)
-#  define XXH32_update XXH_NAME2(XXH_NAMESPACE, XXH32_update)
-#  define XXH32_digest XXH_NAME2(XXH_NAMESPACE, XXH32_digest)
-#  define XXH32_copyState XXH_NAME2(XXH_NAMESPACE, XXH32_copyState)
-#  define XXH32_canonicalFromHash XXH_NAME2(XXH_NAMESPACE, XXH32_canonicalFromHash)
-#  define XXH32_hashFromCanonical XXH_NAME2(XXH_NAMESPACE, XXH32_hashFromCanonical)
-#  define XXH64 XXH_NAME2(XXH_NAMESPACE, XXH64)
-#  define XXH64_createState XXH_NAME2(XXH_NAMESPACE, XXH64_createState)
-#  define XXH64_freeState XXH_NAME2(XXH_NAMESPACE, XXH64_freeState)
-#  define XXH64_reset XXH_NAME2(XXH_NAMESPACE, XXH64_reset)
-#  define XXH64_update XXH_NAME2(XXH_NAMESPACE, XXH64_update)
-#  define XXH64_digest XXH_NAME2(XXH_NAMESPACE, XXH64_digest)
-#  define XXH64_copyState XXH_NAME2(XXH_NAMESPACE, XXH64_copyState)
-#  define XXH64_canonicalFromHash XXH_NAME2(XXH_NAMESPACE, XXH64_canonicalFromHash)
-#  define XXH64_hashFromCanonical XXH_NAME2(XXH_NAMESPACE, XXH64_hashFromCanonical)
-#endif
-
-
-/* *************************************
-*  Version
-***************************************/
-#define XXH_VERSION_MAJOR    0
-#define XXH_VERSION_MINOR    6
-#define XXH_VERSION_RELEASE  5
-#define XXH_VERSION_NUMBER  (XXH_VERSION_MAJOR *100*100 + XXH_VERSION_MINOR *100 + XXH_VERSION_RELEASE)
-XXH_PUBLIC_API unsigned XXH_versionNumber (void);
-
-
-/*-**********************************************************************
-*  32-bit hash
-************************************************************************/
-typedef unsigned int XXH32_hash_t;
-
-/*! XXH32() :
-    Calculate the 32-bit hash of sequence "length" bytes stored at memory address "input".
-    The memory between input & input+length must be valid (allocated and read-accessible).
-    "seed" can be used to alter the result predictably.
-    Speed on Core 2 Duo @ 3 GHz (single thread, SMHasher benchmark) : 5.4 GB/s */
-XXH_PUBLIC_API XXH32_hash_t XXH32 (const void* input, size_t length, unsigned int seed);
-
-/*======   Streaming   ======*/
-typedef struct XXH32_state_s XXH32_state_t;   /* incomplete type */
-XXH_PUBLIC_API XXH32_state_t* XXH32_createState(void);
-XXH_PUBLIC_API XXH_errorcode  XXH32_freeState(XXH32_state_t* statePtr);
-XXH_PUBLIC_API void XXH32_copyState(XXH32_state_t* dst_state, const XXH32_state_t* src_state);
-
-XXH_PUBLIC_API XXH_errorcode XXH32_reset  (XXH32_state_t* statePtr, unsigned int seed);
-XXH_PUBLIC_API XXH_errorcode XXH32_update (XXH32_state_t* statePtr, const void* input, size_t length);
-XXH_PUBLIC_API XXH32_hash_t  XXH32_digest (const XXH32_state_t* statePtr);
-
-/*
- * Streaming functions generate the xxHash of an input provided in multiple segments.
- * Note that, for small input, they are slower than single-call functions, due to state management.
- * For small inputs, prefer `XXH32()` and `XXH64()`, which are better optimized.
- *
- * XXH state must first be allocated, using XXH*_createState() .
- *
- * Start a new hash by initializing state with a seed, using XXH*_reset().
- *
- * Then, feed the hash state by calling XXH*_update() as many times as necessary.
- * The function returns an error code, with 0 meaning OK, and any other value meaning there is an error.
- *
- * Finally, a hash value can be produced anytime, by using XXH*_digest().
- * This function returns the nn-bits hash as an int or long long.
- *
- * It's still possible to continue inserting input into the hash state after a digest,
- * and generate some new hashes later on, by calling again XXH*_digest().
- *
- * When done, free XXH state space if it was allocated dynamically.
- */
-
-/*======   Canonical representation   ======*/
-
-typedef struct { unsigned char digest[4]; } XXH32_canonical_t;
-XXH_PUBLIC_API void XXH32_canonicalFromHash(XXH32_canonical_t* dst, XXH32_hash_t hash);
-XXH_PUBLIC_API XXH32_hash_t XXH32_hashFromCanonical(const XXH32_canonical_t* src);
-
-/* Default result type for XXH functions are primitive unsigned 32 and 64 bits.
- * The canonical representation uses human-readable write convention, aka big-endian (large digits first).
- * These functions allow transformation of hash result into and from its canonical format.
- * This way, hash values can be written into a file / memory, and remain comparable on different systems and programs.
- */
-
-
-#ifndef XXH_NO_LONG_LONG
-/*-**********************************************************************
-*  64-bit hash
-************************************************************************/
-typedef unsigned long long XXH64_hash_t;
-
-/*! XXH64() :
-    Calculate the 64-bit hash of sequence of length "len" stored at memory address "input".
-    "seed" can be used to alter the result predictably.
-    This function runs faster on 64-bit systems, but slower on 32-bit systems (see benchmark).
-*/
-XXH_PUBLIC_API XXH64_hash_t XXH64 (const void* input, size_t length, unsigned long long seed);
-
-/*======   Streaming   ======*/
-typedef struct XXH64_state_s XXH64_state_t;   /* incomplete type */
-XXH_PUBLIC_API XXH64_state_t* XXH64_createState(void);
-XXH_PUBLIC_API XXH_errorcode  XXH64_freeState(XXH64_state_t* statePtr);
-XXH_PUBLIC_API void XXH64_copyState(XXH64_state_t* dst_state, const XXH64_state_t* src_state);
-
-XXH_PUBLIC_API XXH_errorcode XXH64_reset  (XXH64_state_t* statePtr, unsigned long long seed);
-XXH_PUBLIC_API XXH_errorcode XXH64_update (XXH64_state_t* statePtr, const void* input, size_t length);
-XXH_PUBLIC_API XXH64_hash_t  XXH64_digest (const XXH64_state_t* statePtr);
-
-/*======   Canonical representation   ======*/
-typedef struct { unsigned char digest[8]; } XXH64_canonical_t;
-XXH_PUBLIC_API void XXH64_canonicalFromHash(XXH64_canonical_t* dst, XXH64_hash_t hash);
-XXH_PUBLIC_API XXH64_hash_t XXH64_hashFromCanonical(const XXH64_canonical_t* src);
-#endif  /* XXH_NO_LONG_LONG */
-
-
-
-#ifdef XXH_STATIC_LINKING_ONLY
-
-/* ================================================================================================
-   This section contains declarations which are not guaranteed to remain stable.
-   They may change in future versions, becoming incompatible with a different version of the library.
-   These declarations should only be used with static linking.
-   Never use them in association with dynamic linking !
-=================================================================================================== */
-
-/* These definitions are only present to allow
- * static allocation of XXH state, on stack or in a struct for example.
- * Never **ever** use members directly. */
-
-#if !defined (__VMS) \
-  && (defined (__cplusplus) \
-  || (defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */) )
-#   include <stdint.h>
-
-struct XXH32_state_s {
-   uint32_t total_len_32;
-   uint32_t large_len;
-   uint32_t v1;
-   uint32_t v2;
-   uint32_t v3;
-   uint32_t v4;
-   uint32_t mem32[4];
-   uint32_t memsize;
-   uint32_t reserved;   /* never read nor write, might be removed in a future version */
-};   /* typedef'd to XXH32_state_t */
-
-struct XXH64_state_s {
-   uint64_t total_len;
-   uint64_t v1;
-   uint64_t v2;
-   uint64_t v3;
-   uint64_t v4;
-   uint64_t mem64[4];
-   uint32_t memsize;
-   uint32_t reserved[2];          /* never read nor write, might be removed in a future version */
-};   /* typedef'd to XXH64_state_t */
-
-# else
-
-struct XXH32_state_s {
-   unsigned total_len_32;
-   unsigned large_len;
-   unsigned v1;
-   unsigned v2;
-   unsigned v3;
-   unsigned v4;
-   unsigned mem32[4];
-   unsigned memsize;
-   unsigned reserved;   /* never read nor write, might be removed in a future version */
-};   /* typedef'd to XXH32_state_t */
-
-#   ifndef XXH_NO_LONG_LONG  /* remove 64-bit support */
-struct XXH64_state_s {
-   unsigned long long total_len;
-   unsigned long long v1;
-   unsigned long long v2;
-   unsigned long long v3;
-   unsigned long long v4;
-   unsigned long long mem64[4];
-   unsigned memsize;
-   unsigned reserved[2];     /* never read nor write, might be removed in a future version */
-};   /* typedef'd to XXH64_state_t */
-#    endif
-
-# endif
-
-
-#if defined(XXH_INLINE_ALL) || defined(XXH_PRIVATE_API)
-#  include "xxhash.c"   /* include xxhash function bodies as `static`, for inlining */
-#endif
-
-#endif /* XXH_STATIC_LINKING_ONLY */
-
-
-#if defined (__cplusplus)
-}
-#endif
-
-#endif /* XXHASH_H_5627135585666179 */
diff --git a/cpp/vcpkg.json b/cpp/vcpkg.json
index bb38a3bd46..4c1f3e0fe1 100644
--- a/cpp/vcpkg.json
+++ b/cpp/vcpkg.json
@@ -5,6 +5,10 @@
     "fmt",
     "spdlog",
     "pcre",
+    {
+      "name": "xxhash",
+      "$version reason": "Must match version in conda build for interoperability"
+    },
     {
       "name": "protobuf",
       "default-features": false,
@@ -162,6 +166,7 @@
     { "name": "rapidcheck", "version": "2021-12-20" },
     { "name": "s2n", "version": "1.3.5" },
     { "name": "spdlog", "version": "1.11.0" },
+    { "name": "xxhash", "version": "0.8.2" },
     { "name": "zlib", "version": "1.2.13" },
     { "name": "zstd", "version": "1.5.2" }
   ],
diff --git a/environment_unix.yml b/environment_unix.yml
index 2df079d92f..a24238e060 100644
--- a/environment_unix.yml
+++ b/environment_unix.yml
@@ -42,9 +42,9 @@ dependencies:
   # ArcticDB is currently incompatible with fmt 10
   - fmt < 10
   - folly
-  # Vendored build dependencies (see `cpp/thirdparty`)
+  # Vendored build dependencies (see `cpp/thirdparty` and `cpp/vcpkg.json`)
   # Versions must be kept in sync
-  - xxhash
+  - xxhash==0.8.2
   - semimap
   - robin_hood
   - rapidcheck


Test patch:
diff --git a/python/tests/unit/arcticdb/version_store/test_aggregation.py b/python/tests/unit/arcticdb/version_store/test_aggregation.py
index 1b841f2edf..4bfb56edce 100644
--- a/python/tests/unit/arcticdb/version_store/test_aggregation.py
+++ b/python/tests/unit/arcticdb/version_store/test_aggregation.py
@@ -22,10 +22,7 @@
 from hypothesis import assume, given, settings
 from hypothesis.extra.pandas import column, data_frames, range_indexes
 
-from tests.util.mark import xfail_on_linux_conda
 
-
-@xfail_on_linux_conda(reason="Test fails on linux conda, should be fixed by issue #1035")
 def test_group_on_float_column_with_nans(lmdb_version_store):
     lib = lmdb_version_store
     sym = "test_group_on_float_column_with_nans"
diff --git a/python/tests/util/mark.py b/python/tests/util/mark.py
index b4534465a4..dd09b5004f 100644
--- a/python/tests/util/mark.py
+++ b/python/tests/util/mark.py
@@ -47,13 +47,6 @@
 Currently controlled by the ARCTICDB_PERSISTENT_STORAGE_TESTS and ARCTICDB_FAST_TESTS_ONLY env vars."""
 
 
-def xfail_on_linux_conda(reason=""):
-    def decorator(func):
-        return pytest.mark.xfail(ARCTICDB_USING_CONDA and sys.platform == "linux", reason=reason)(func)
-
-    return decorator
-
-
 def _no_op_decorator(fun):
     return fun