qtcreator supports both qmake and cmake for cross platform development and
qmake works fine for both msvc and MinGW builds on Windows. However, I'd prefer to support just one tool: cmake.
The CMakeLists.txt at via-httplib works fine on linux and when using cmake to build msvc on Windows. 
However, when using cmake to build MinGW on Windows, I get the following error:
CMake Error at C:/Program Files/CMake/share/cmake-3.13/Modules/FindBoost.cmake:2100 (message):
Unable to find the requested Boost libraries.Boost version: 1.69.0
Boost include path: D:/DevLibraries/boost/boost_1_69_0
Could not find the following Boost libraries:
boost_systemNo Boost libraries were found. You may need to set BOOST_LIBRARYDIR to the directory containing Boost libraries or BOOST_ROOT to the location of Boost.
Both the BOOST_LIBRARYDIR and BOOST_ROOT environment variables are set and are found when using the Visual Studio 15 2017 Win64 generator and default native compilers
The error message indicates that when using the MinGW Makefiles and default native compilers, cmake finds the BOOST_ROOT environment variable but not BOOST_LIBRARYDIR. So it does not seem to be the same problem described here: Cmake doesn't find Boost
Is this a bug in FindBoost.cmake? Is there a "work around"?