[question] Conan Libraries Support for CMake v4.2

[esswl]

What is your question?

Hi, I am using Conan on Visual Studio 2026 and support for the Visual Studio 2026 generator was added in CMake 4.2. Thus, I can only use CMake 4.2. However, I realize that quite a few libraries such as Thrift, My SQL Connector and Grpc have tool_requires that is a cmake <4. May I ask if it is possible for all Conan libraries to support all CMake versions including 4.2.x? Thanks!

[leha-bot]

Hello, I had a similar problem with vs2026 (see my comment here and fix for benchmark here: #29696 ). I think that your issue is a good candidate to collect all recipes which didn't build with visual studio 2026 (and, in most cases, cmake 4.2 support) 👍

[jcar87]

Thanks for reporting this!

A lot of the recipes still have CMake <4, this was done before CMake 4 was even released, under the assumption that it would come with breaking changes. As it stands, it did come with breaking changes, and the <4 actually does help in a few instances where the recipes are not actually compatible with CMake 4.

However, in a lot of other cases, it is clipping CMake to <4, which should be fine for most cases, except for visual Studio 2026 support.

We've been addressing this in recipes as we go, but in the meantime, you can work around this by adding this to your Conan profile(s) on Windows - it will tell Conan to just use the most recent CMake it can find in your local cache (or a remote if there's none in the local), regardless of what the recipe says

[replace_tool_requires]
cmake/*: cmake/[*]

or just be explicit:

[replace_tool_requires]
cmake/*: cmake/4.2.1

[leha-bot]

I also used the double "spell" in my own config:
(N.B.: exclamation mark is a brand new Conan 2.26 feature (AFAIK))

[replace_tool_requires]
cmake/3.*: cmake/4.2.3

[tool_requires]
!cmake/*: cmake/4.2.3