Add cmake-init generated CMake files

[ClausKlein]

• Add and use cmake workflow presets file
• Use CMAKE_VERIFY_INTERFACE_HEADER_SETS
• Use ccache if available
• use debug postfix
• install libray to lib
• install less verbose
• test installed cmake config package
• install the c++20 CXX_MODULE
• compiles with Apple clang version 16.0.0 (std=c++2b, but no CXX_MODULE support yet!)
• compiles with clang version 20 (std=c++2b)
• MSVC works on CI (std=c++20, but fails to compile the CXX_MODULE)
• Activate the find installed CXX_MODULE test on CI!
• g++-15 fails on macOS with both versions?

see too https://anarthal.github.io/cppblog/modules2

[ClausKlein]

NOTE: the asio module

but MSVC does not compile it:

[5/8] Building CXX object CMakeFiles\asio_module.dir\D_\a\asio\asio\asio\stagedir\lib\cmake\asio\module\asio.cppm.obj
asio.cppm
Please define _WIN32_WINNT or _WIN32_WINDOWS appropriately. For example:
- add -D_WIN32_WINNT=0x0601 to the compiler command line; or
- add _WIN32_WINNT=0x0601 to your project's Preprocessor Definitions.
Assuming _WIN32_WINNT=0x0601 (i.e. Windows 7 target).
D:\a\asio\asio\asio\stagedir\include\asio/detail/impl/win_mutex.ipp(39): note: sorry: 'inline' function definition for 
'int asio::detail::win_mutex::do_init(void)' could not be written to module due to unrecognized expression
 or statement at 'D:\a\asio\asio\asio\stagedir\include\asio/detail/impl/win_mutex.ipp(55)'.
If possible please provide a repro here: https://developercommunity.visualstudio.com/

[ClausKlein]

Windows makes me crazy:

FAILED: CMakeFiles/main.dir/main.cpp.obj 
C:\PROGRA~1\MICROS~2\2022\ENTERP~1\VC\Tools\MSVC\1442~1.344\bin\Hostx64\x64\cl.exe  /nologo /TP -DASIO_DISABLE_BOOST_CONTEXT_FIBER -DASIO_HAS_SNPRINTF -DASIO_NO_DEPRECATED -DUSE_MODULES -external:I"C:\Program Files\OpenSSL\include" -external:W0 /DWIN32 /D_WINDOWS /EHsc /Ob0 /Od /RTC1 -std:c++latest -MDd -Zi /showIncludes @CMakeFiles\main.dir\main.cpp.obj.modmap /FoCMakeFiles\main.dir\main.cpp.obj /FdCMakeFiles\main.dir\ /FS -c D:\a\asio\asio\asio\module\tests\main.cpp
D:\a\asio\asio\asio\module\tests\main.hpp(36): error C2039: 'stream_truncated': is not a member of 'asio::ssl::error'
D:\a\asio\asio\asio\stagedir\lib\cmake\asio\module\asio.cppm(66): note: see declaration of 'asio::ssl::error'
D:\a\asio\asio\asio\module\tests\main.hpp(36): error C2065: 'stream_truncated': undeclared identifier
D:\a\asio\asio\asio\module\tests\main.hpp(44): error C2039: 'promise_type': is not a member of 'std::coroutine_traits<asio::awaitable<void,asio::any_io_executor>,asio::ip::tcp::socket>'
C:\Program Files\Microsoft Visual Studio\2022\Enterprise\VC\Tools\MSVC\14.42.34433\include\coroutine(46): note: see declaration of 'std::coroutine_traits<asio::awaitable<void,asio::any_io_executor>,asio::ip::tcp::socket>'
D:\a\asio\asio\asio\module\tests\main.hpp(58): error C2039: 'promise_type': is not a member of 'std::coroutine_traits<asio::awaitable<void,asio::any_io_executor>>'
C:\Program Files\Microsoft Visual Studio\2022\Enterprise\VC\Tools\MSVC\14.42.34433\include\coroutine(46): note: see declaration of 'std::coroutine_traits<asio::awaitable<void,asio::any_io_executor>>'
D:\a\asio\asio\asio\module\tests\main.hpp(63): error C2440: 'initializing': cannot convert from 'initializer list' to 'asio::basic_socket_acceptor<asio::ip::tcp,asio::any_io_executor>'

[anarthal]

I encountered and reported the first error you mention: https://developercommunity.visualstudio.com/t/Using-__try-in-an-inline-function-in-a-h/10186252
It's supposedly fixed but not released.
The other ones are likely a problem with the "export using" approach, which I believe can't be used with MSVC. I think what you're encountering is what I describe here: https://anarthal.github.io/cppblog/modules2#template-spec

[ClausKlein]

Thank you!

[ClausKlein]

Is this OK?

[ClausKlein]

@anarthal This was my quick solution for ths MSVC inline problem

[anarthal]

Looks like GitHub had an issue yesterday, I got some 500 errors when trying to post my comments.

This doesn't do what you'd expect. SEH __catch clauses do catch C++ exceptions, but C++ catch doesn't catch SEH exceptions AFAIK. There's no std::bad_alloc exception in SEH to begin with.

If I'm not mistaken, the SEH handler there is only relevant for Windows XP/Windows Server 2003 and previous versions (see the InitializeCriticalSection docs). I don't think you can target these systems with a C++20 compiler, so you can likely remove the SEH try/catch in your prototype without loss of functionality.

[ClausKlein]

@anarthal This was my quick solution for ths MSVC inline problem

[anarthal]

Same applies here.

[ClausKlein]

The remaining problem seems a const problem to be:

cannot convert argument 1 from 'asio::this_coro::executor_t' to 'const asio::any_io_executor &'

C:\PROGRA~1\MICROS~2\2022\ENTERP~1\VC\Tools\MSVC\1442~1.344\bin\Hostx64\x64\cl.exe  /nologo /TP -DASIO_DISABLE_BOOST_CONTEXT_FIBER -DASIO_HAS_SNPRINTF -DASIO_NO_DEPRECATED -DUSE_MODULES -external:I"C:\Program Files\OpenSSL\include" -external:W0 /DWIN32 /D_WINDOWS /EHsc /Ob0 /Od /RTC1 -std:c++latest -MDd -Zi /showIncludes @CMakeFiles\main.dir\main.cpp.obj.modmap /FoCMakeFiles\main.dir\main.cpp.obj /FdCMakeFiles\main.dir\ /FS -c D:\a\asio\asio\asio\module\tests\main.cpp
D:\a\asio\asio\asio\module\tests\main.hpp(49): error C2039: 'promise_type': is not a member of 'std::coroutine_traits<asio::awaitable<void,asio::any_io_executor>,asio::ip::tcp::socket>'
C:\Program Files\Microsoft Visual Studio\2022\Enterprise\VC\Tools\MSVC\14.42.34433\include\coroutine(46): note: see declaration of 'std::coroutine_traits<asio::awaitable<void,asio::any_io_executor>,asio::ip::tcp::socket>'
D:\a\asio\asio\asio\module\tests\main.hpp(58): error C2039: 'promise_type': is not a member of 'std::coroutine_traits<asio::awaitable<void,asio::any_io_executor>>'
C:\Program Files\Microsoft Visual Studio\2022\Enterprise\VC\Tools\MSVC\14.42.34433\include\coroutine(46): note: see declaration of 'std::coroutine_traits<asio::awaitable<void,asio::any_io_executor>>'
D:\a\asio\asio\asio\module\tests\main.hpp(63): error C2440: 'initializing': cannot convert from 'initializer list' to 'asio::basic_socket_acceptor<asio::ip::tcp,asio::any_io_executor>'
D:\a\asio\asio\asio\module\tests\main.hpp(63): note: 'asio::basic_socket_acceptor<asio::ip::tcp,asio::any_io_executor>::basic_socket_acceptor': no overloaded function could convert all the argument types
D:\a\asio\asio\asio\stagedir\include\asio\basic_socket_acceptor.hpp(134): note: could be 'asio::basic_socket_acceptor<asio::ip::tcp,asio::any_io_executor>::basic_socket_acceptor(const asio::any_io_executor &)'
D:\a\asio\asio\asio\module\tests\main.hpp(63): note: 'asio::basic_socket_acceptor<asio::ip::tcp,asio::any_io_executor>::basic_socket_acceptor(const asio::any_io_executor &)': cannot convert argument 1 from 'asio::this_coro::executor_t' to 'const asio::any_io_executor &'
D:\a\asio\asio\asio\module\tests\main.hpp(63): note: Reason: cannot convert from 'asio::this_coro::executor_t' to 'const asio::any_io_executor'
D:\a\asio\asio\asio\module\tests\main.hpp(63): note: No user-defined-conversion operator available that can perform this conversion, or the operator cannot be called

[ClausKlein]

I got the CXX_MODULE work for the fmt library:

https://github.com/ClausKlein/fmt-module

[anarthal]

The other issue you're seeing is likely due to this warning you're getting:

D:\a\asio\asio\asio\stagedir\lib\cmake\asio\module\asio.cppm(48): warning C5304: a declaration designated by the using-declaration 'asio::this_coro::executor' exported from this module has internal linkage and using such a name outside the module is ill-formed; consider declaring 'const asio::this_coro::executor_t asio::this_coro::executor' 'inline' to use it outside of this module

Which is related to this: constexpr variables must be marked inline, otherwise they have internal linkage and can't be exported.

Actually, Asio declares them as ASIO_INLINE_VARIABLE, which conditionally expands to inline when there's support from the compiler (see config.hpp.

This, however, relies on __cplusplus being correctly defined, which is not the case by default for MSVC. IIRC there's a command line switch (was it /Zc:__cplusplus?) to solve it. Have a try with this.

[anarthal]

By the way, what is your final intention with this repository? Are you planning to PR it to Asio, or is it just to experiment?

[ClausKlein]

By the way, what is your final intention with this repository? Are you planning to PR it to Asio, or is it just to experiment?

Both, but no success to add cmake support to the asio cmake PR

But a a site effect, I created issues or pushed small fixes.

I found a better way and dit it for boost, fmt, asio: a cmake adapter to improve the cmake support.

i.e.

• https://github.com/ClausKlein/asio.cmake
• https://github.com/ClausKlein/boost-cmake
• https://github.com/ClausKlein/fmt-module