title: How to build flann in windows 10 from source?
body: <p>I was trying to build flann from source in Windows-10 using cmake. During the installation process it says it cannot find liblz4. 
  I tried two method : </p>
  
  <p>1) So I downloaded the prebuild lz4 from here (<a href="https://github.com/lz4/lz4/releases" rel="nofollow noreferrer">https://github.com/lz4/lz4/releases</a>) and placed the C:\XXXX\Downloads\lz4_v1_9_1_win64\dll to my env path. </p>
  
  <p>2) I used vcpkg to install lz4 first. Then did
  <code>C:\source\flann\build&gt; cmake .. -DCMAKE_TOOLCHAIN_FILE=C:\XXXXXX\source\vcpkg\scripts\buildsystems\vcpkg.cmake -G "Visual Studio 15 2017 Win64"</code>.</p>
  
  <p>None of the above two method worked. I still get cannot find liblz4 error. </p>
  
  <p><code>-- Found PkgConfig: C:/XXXXXX/Downloads/cmake-3.13.3-win64-x64/bin/pkg-config.exe (found version "0.26")                                                                                 -- Checking for module 'liblz4'                                                                                                                                                                  --   No package 'liblz4' found                                                                                                                                                                   CMake Error at C:/Program Files/CMake/share/cmake-3.13/Modules/FindPkgConfig.cmake:452 (message):                                                                                                  A required package was not found                                                                                                                                                               Call Stack (most recent call first):                                                                                                                                                               C:/Program Files/CMake/share/cmake-3.13/Modules/FindPkgConfig.cmake:622 (_pkg_check_modules_internal)                                                                                            CMakeLists.txt:150 (pkg_check_modules)                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           -- Configuring incomplete, errors occurred!                                                                                                                                                      See also "C:/XXXXXXX/source/flann/build/CMakeFiles/CMakeOutput.log".</code></p>