Re: [boost] Proposal for moving Boost to CMake

On Jun 16, 2017, at 11:24 PM, David Sankel via Boost wrote:

On Fri, Jun 16, 2017 at 9:01 PM, Robert Ramey via Boost < boost@lists.boost.org> wrote:

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On 6/16/17 4:44 PM, David Sankel via Boost wrote:

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* Boost sources would provide a compatible, drop-in replacement for the 'FindBoost' module that is distributed with CMake. A CMake-based application could point to it and, instead of using the system Boost libraries, Boost targets would be built from source as part of the user build.

Hmmm would this be a FindBoost for the whole of Boost or for each particular library? Who would re-write and maintain this FindBoost as the current one is not up the task. Getting this right - or even better is not a trivial task.

I agree that this is a non-trivial task. The contract for FindBoost is relatively straightforward. The implementation for the Boost-source version of this library would look at the COMPONENTS argument and, based on that, add_subdirectory the source for the particularly requested library. The CMakeLists.txt file would be author maintained and provide its corresponding target (e.g. boost::thread).

Thats not the the way `find_package` works at all. The `find_package` is used to find packages installed, it should never go out and build libraries. If the user wants to add boost to their build(or set of libraries), you would use `add_subdirectory` directly and then override `find_package` to ignore boost packages, and then use the `boost::` alias targets provided.