Compile c++ project without makefile neither CMakeLists.txt - c++

Question

How can I easily compile a c++ project ( https://github.com/eduardovera/D-KHT ) that doesn't have any makefile neither CMakeLists.txt?

Answer 1

Projects that don't have a build script, and are not header-only libraries, are virtually useless. Building them manually requires issuance of dozens or hundreds of commands, and is not tractable. Build scripts are there for a reason. Use them! They make hard work easy. If you use them properly, that is.
There is some confusion in your project: Qt Creator is an IDE. You don't need it to build anything.
Building qmake-based Projects From Command Line
macOS/Linux
# assume the git checkout is in the wc folder in the current directory
# uses system default Qt installation
mkdir build
cd build
qmake ../src
make
Windows Command Prompt
:: Assume the git checkout is in the wc folder in the current directory
:: BuildTools can be also Community, Professional or Enterprise - based on what
:: Visual Studio variant you have installed
:: 2019 can be 2017 (again - depends on what you got)
C:\Program Files (x86)\Microsoft Visual Studio\2017\BuildTools\VC\Auxiliary\Build\vcvarsall x64
mkdir build
cd build
C:\Qt\5.15.0\msvc2019_64\bin\qmake ..\src
nmake
:: For faster builds, use jom instead of nmake:
C:\Qt\Tools\QtCreator\bin\jom
Note that the path to visual studio installation and the path to Qt installation effectively select the compiler and Qt version. Do not modify the global environment PATH! Instead, you could add a bin folder to your home directory, add that to the path, and add symlinks there to your chosen vcvarsall.bat and qmake.exe.
CMake
But in any case - don't use qmake and make. Use cmake and ninja instead. You'd replace all qmake calls with cmake, and all [n]make calls with ninja. To pass Qt installation path to cmake, use the following options: -DCMAKE_PREFIX_PATH=<path to your Qt install>
macOS/Linux
# assume the git checkout is in the wc folder in the current directory
mkdir build
cd build
cmake -GNinja ../src
ninja
Windows Command Prompt
:: Assume the git checkout is in the wc folder in the current directory
:: BuildTools can be also Community, Professional or Enterprise - based on what
:: Visual Studio variant you have installed
:: 2019 can be 2017 (again - depends on what you got)
C:\Program Files (x86)\Microsoft Visual Studio\2017\BuildTools\VC\Auxiliary\Build\vcvarsall x64
mkdir build
cd build
C:\Qt\Tools\CMake_64\bin\cmake -GNinja -DCMAKE_PREFIX_PATH=C:\Qt\5.15.0\msvc2019_64 ..\src
C:\Qt\Tools\Ninja\ninja
When to Run What
Once in a Given Command Prompt
On Windows, the vcvarsall script has to run only once in any given command prompt window. It sets up environment variables needed to find and run the compiler and related tools.
Once in a Given Build Folder
The build script generators qmake and cmake need to be run only once in a given build folder. But qmake is abysmal at dealing with changes that go too far, so in practice you often have to re-run it manually. cmake normally has no such problems - it will re-run itself as needed.
Once Per Build
The build tool itself: ninja, ideally. Or make (on Unix), or jom (on Windows), or nmake (on Windows, if you hate yourself - it's slow).

Answer 2

If a cmake support is missing for an open source project, you can add it.
I created one that let's you run main.cpp, which seemed to be what you wanted. But lacking Qt on my computer, I dropped the dependency to it. I tried with Visual Studio 2019 and it seems to work with the examples in the repo. (Note that you have to create a folder "output" before you run though.)
You should be able to clone https://github.com/eduardovera/D-KHT/pull/3 and run cmake like normal now.

Answer 3

The easiest way to compile a c++ program is to go to your terminal find where your file is stored cd into that path, and then use g++ filename.cpp. And when you run it use ./a.out.