Building on macOS

[TarekSalama]

On M4 Macbook. Trying to compile and I got this error when I ran ./configure --compiler="$(brew --prefix llvm)/bin/clang" --download-nyan

The compiler doesn't support required C++20 features:
  * Concepts
  * Default comparisons
The following versions support these features:
  * clang++ >= 10
  * g++ >= 10
  * Microsoft Visual Studio 2019 >= 16.8
Please upgrade your compiler to build openage.


CMake Error at buildsystem/CheckCompilerFeatures.cmake:57 (message):
  aborting
Call Stack (most recent call first):
  CMakeLists.txt:174 (include)

I tried this earlier and it seems like it should compile but I am unsure what's going on:

(brew --prefix llvm)/bin/clang++ -std=c++20 /Users/tarek/Downloads/test.cpp  -o test_cpp20
tarek@Mac openage % ./test_cpp20
Testing Concept: 6
Testing Comparison (p1 < p2): true
Testing Comparison (p1 == p1): true

[heinezen]

Can you try to compile and run the source code in

openage/buildsystem/CheckCompilerFeatures.cmake

Lines 12 to 39 in 2e40e68

	#include <compare>
	#include <concepts>
	class Cat {
	public:
	virtual int maunz() const { return 42; };
	auto operator <=>(const Cat &other) const = default;
	};
	template <typename T>
	concept Meowable = std::same_as<T, Cat> || std::derived_from<T, Cat>;
	template <Meowable T>
	int meow(const T &cat) {
	return cat.maunz();
	}
	class HouseCat : public Cat {
	public:
	int maunz() const override { return 1337; };
	};
	int main() {
	HouseCat mrr{};
	Cat rrarrr{};
	return meow(mrr) > meow(rrarrr) ? 0 : 1;
	}

That is what the buildsystem uses to test compiler support.

[TarekSalama]

I got this error

|  _)/ _____|_______|_______|_  |
| | ( (____  _____      _     | |    ___  ____  _____ ____  _____  ____ _____
| |  \____ \|  ___)    | |    | |   / _ \|  _ \| ___ |  _ \(____ |/ _  | ___ |
| |_ _____) ) |        | |   _| |  | |_| | |_| | ____| | | / ___ ( (_| | ____|
|___|______/|_|        |_|  (___|   \___/|  __/|_____)_| |_\_____|\___ |_____)
                                         |_|                     (_____|

Welcome to the SFT technologies computer-aided openage build system!

You have chosen, or been chosen, to attempt the daring task of building openage.
If you have installed all the dependencies that are conveniently listed in
[doc/building.md], this _might_ just work!

If it doesn't, consider reporting the issue, or ask for help:
  * GitHub: https://github.com/SFTtech/openage
  * Matrix: #sfttech:matrix.org

-- The CXX compiler identification is AppleClang 16.0.0.16000026
-- Detecting CXX compiler ABI info
-- Detecting CXX compiler ABI info - done
-- Check for working CXX compiler: /Library/Developer/CommandLineTools/usr/bin/c++ - skipped
-- Detecting CXX compile features
-- Detecting CXX compile features - done
CMake Warning at buildsystem/HandleCXXOptions.cmake:75 (message):
  GNU gold linker isn't available, using the default system linker.
Call Stack (most recent call first):
  buildsystem/HandleCXXOptions.cmake:107 (try_enable_gold_linker)
  CMakeLists.txt:173 (include)


-- Performing Test HAVE_REQUIRED_CXX20_SUPPORT
-- Performing Test HAVE_REQUIRED_CXX20_SUPPORT - Success
-- Could NOT find Python3 (missing: Python3_NumPy_INCLUDE_DIRS NumPy) (found suitable exact version "3.13.2")
-- Found Python: /opt/homebrew/bin/python3.13 (Required is at least version "3.9")
Traceback (most recent call last):
  File "<string>", line 1, in <module>
    import cython; print(cython.__version__)
    ^^^^^^^^^^^^^
ModuleNotFoundError: No module named 'cython'
CMake Error at buildsystem/modules/FindPython.cmake:150 (message):
  failed:

  /opt/homebrew/bin/python3.13 -c 'import cython; print(cython.__version__)'

Call Stack (most recent call first):
  buildsystem/modules/FindCython.cmake:14 (py_exec)
  buildsystem/HandlePythonOptions.cmake:7 (find_package)
  CMakeLists.txt:176 (include)


-- Configuring incomplete, errors occurred!

[TheJJ]

ok, so the compile error resolved itself? how?

now you need to have cython installed.

[Skosulor]

The first error was probably solved by changing the configuration command to use clang++ instead of clang.

./configure --compiler="$(brew --prefix llvm)/bin/clang++" --download-nyan