QtCreator 10 and C++20 modules

[devloop]

Is it possible to use Qt Creator 10, on Linux, with CMake 3.26.4 and Clang 16 or Clang 17?

Because I can build code with modules from terminal, but Clang complains that it: Could not build module 'std', as soon as I add module;.

[odelaune]

@devloop said in QtCreator 10 and C++20 modules:

module

It is probably related to QTCREATORBUG-28465.

[SGaist]

Hi and welcome to devnet,

Did you enable C++ 20 in your CMakeLists.txt ?

[devloop]

Hi @SGaist,

Thank you for your hospitality.

Here what I tried:

cmake_minimum_required(VERSION 3.26)
set(CMAKE_CXX_STANDARD 20)
set(CMAKE_CXX_STANDARD_REQUIRED ON)
set(LLVM_ENABLE_LIBCXX ON)
set(CMAKE_INCLUDE_CURRENT_DIR ON)

set(CMAKE_EXPERIMENTAL_CXX_MODULE_DYNDEP 1)
set(CMAKE_EXPERIMENTAL_CXX_MODULE_CMAKE_API "aa1f7df0-828a-4fcd-9afc-2dc80491aca7")
set(CXX_SCAN_FOR_MODULES ON)

[SGaist]

Do you mean that with that configuration, it works in the terminal ?

[devloop]

@SGaist

Knowing that the CMAKE_EXPERIMENTAL_CXX_MODULE_CMAKE_API have to be changed, according to some setup, etc., yes, I can build, from a terminal, with this kind of configuration, for instance with a command like cmake -GNinja ..

But it does not work with Qt Creator.

Indeed, as soon as I add any line related to modules, like module; I get an error from Qt Creator: Could not build module 'std'.

[odelaune]

@devloop said in QtCreator 10 and C++20 modules:

module

It is probably related to QTCREATORBUG-28465.

[devloop]

@odelaune

Thanks, but why writing this :

This is the only thing that clangd doesn't do automatically and thats why it shows false-positives errors in current QtCreator (based on outdated BMI).

While it is more than false-positives errors, as it does not even compile from Qt Creator?

[devloop]

@odelaune

After cleaning all build files, etc., it appears that you were right.

Unfortunately, even Qt Creator 11 does not address the issue…