# cmake 3.28.0-rc3 fails to build qt6 via vcpkg

**URL:** https://discourse.cmake.org/t/cmake-3-28-0-rc3-fails-to-build-qt6-via-vcpkg/9369
**Category:** Development
**Tags:** os:windows
**Created:** [November 5, 2023, 6:28pm UTC](https://discourse.cmake.org/t/cmake-3-28-0-rc3-fails-to-build-qt6-via-vcpkg/9369 "2023-11-05T18:28:11Z")
**Posts on this page:** 6
**Page:** 1

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### Author: ![Tobias](https://discourse.cmake.org/letter_avatar_proxy/v4/letter/t/c67d28/32.png) [@Tobias](https://discourse.cmake.org/u/Tobias)
#### Post date: [November 5, 2023, 6:28pm UTC](https://discourse.cmake.org/t/cmake-3-28-0-rc3-fails-to-build-qt6-via-vcpkg/9369/1 "2023-11-05T18:28:11Z")

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Hi,

I just tried to build qt6 via vcpkg and it failed. I first thought it is a vcpkg problem but switching to 3.27 solved it (and failed later due to a different error)

The error message was:

CMake Error in C:/Development/vcpkg-clion/vcpkg/buildtrees/qtbase/x64-windows-rel/CMakeFiles/CMakeScratch/TryCompile-qarcjy/CMakeLists.txt:  
The target named “cmTC\_fd527” has C++ sources that may use modules, but  
modules are not supported by this generator. See the cmake-cxxmodules(7)  
manual and the CMAKE\_CXX\_SCAN\_FOR\_MODULES variable.

System specs:

- win11, 64 bit
- MSVC 19.37.32822.0
- cmake 3.28.0-rc3

Regards  
Tobias

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### Author: ![ben.boeckel](https://discourse.cmake.org/letter_avatar_proxy/v4/letter/b/ea5d25/32.png) [@ben.boeckel](https://discourse.cmake.org/u/ben.boeckel)
#### Post date: [November 5, 2023, 10:26pm UTC](https://discourse.cmake.org/t/cmake-3-28-0-rc3-fails-to-build-qt6-via-vcpkg/9369/2 "2023-11-05T22:26:41Z")

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Can you please test `release` branch directly? This MR should have fixed this: [https://gitlab.kitware.com/cmake/cmake/-/merge\_requests/8925](https://gitlab.kitware.com/cmake/cmake/-/merge_requests/8925)

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<div class="post-metadata">

### Author: ![Tobias](https://discourse.cmake.org/letter_avatar_proxy/v4/letter/t/c67d28/32.png) [@Tobias](https://discourse.cmake.org/u/Tobias)
#### Post date: [November 5, 2023, 10:33pm UTC](https://discourse.cmake.org/t/cmake-3-28-0-rc3-fails-to-build-qt6-via-vcpkg/9369/3 "2023-11-05T22:33:33Z")

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sorry, I just stumbled on this so I have no experience. What’s the easiest way to do this? Is there a pre-built version somewhere or do I have to build cmake myself?

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### Author: ![ben.boeckel](https://discourse.cmake.org/letter_avatar_proxy/v4/letter/b/ea5d25/32.png) [@ben.boeckel](https://discourse.cmake.org/u/ben.boeckel)
#### Post date: [November 5, 2023, 10:40pm UTC](https://discourse.cmake.org/t/cmake-3-28-0-rc3-fails-to-build-qt6-via-vcpkg/9369/4 "2023-11-05T22:40:54Z")

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There are nightly `master` builds here: [https://cmake.org/files/dev/?C=M;O=D](https://cmake.org/files/dev/?C=M;O=D) It was merged on 1 Nov, so if it is broken on 31 Oct and works on 1 Nov or 2 Nov, that would be a good indicator that it is fixed. But rc4 should be out this week.

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<div class="post-metadata">

### Author: ![Tobias](https://discourse.cmake.org/letter_avatar_proxy/v4/letter/t/c67d28/32.png) [@Tobias](https://discourse.cmake.org/u/Tobias)
#### Post date: [November 6, 2023, 6:00am UTC](https://discourse.cmake.org/t/cmake-3-28-0-rc3-fails-to-build-qt6-via-vcpkg/9369/5 "2023-11-06T06:00:37Z")

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I used the nightly from the 5th and can’t reproduce it.

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### Author: ![ben.boeckel](https://discourse.cmake.org/letter_avatar_proxy/v4/letter/b/ea5d25/32.png) [@ben.boeckel](https://discourse.cmake.org/u/ben.boeckel)
#### Post date: [November 6, 2023, 8:01pm UTC](https://discourse.cmake.org/t/cmake-3-28-0-rc3-fails-to-build-qt6-via-vcpkg/9369/6 "2023-11-06T20:01:22Z")

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Thanks. rc4 is out now as well.