To avoid loosing the script I use to build Qt 5 on Windows, here is the latest version I’m using. Note that I’m compiling using Visual Studio 2019 and I disable things I don’t need to try to minimize build time.

Edit 2019-10-17: Removed accessibility and harfbuzz

@echo off

::
:: Configure Visual Studio 2019 Community for x64 build.
::
call "C:\Program Files (x86)\Microsoft Visual Studio\2019\Community\VC\Auxiliary\Build\vcvarsall.bat" x64

::
:: Set Qt directory and set it as the current one.
::
set QT_DIR=C:\Development\Libs\Qt\5.13.1
pushd "%QT_DIR%\Src"

::
:: Configure Qt
::
call configure -release             ^
    -static                         ^
    -opensource -confirm-license    ^
    -prefix "%QT_DIR%/static"       ^
    -platform win32-msvc            ^
    -mp                             ^
    -c++std c++17                   ^
    -no-accessibility               ^
    -no-icu                         ^
    -no-harfbuzz                    ^
    -nomake examples                ^
    -nomake tests                   ^
    -skip qtwebengine               ^
    -skip qt3d

::
:: Build and install
::
nmake
nmake install

::
:: Restore the previous working directory
::
popd