MSBuildToolchain

Warning

This is an experimental feature subject to breaking changes in future releases.

The MSBuildToolchain can be used in the toolchain() method:

from conans import ConanFile, MSBuildToolchain

class App(ConanFile):
    settings = "os", "arch", "compiler", "build_type"
    requires = "hello/0.1"
    generators = "msbuild"
    options = {"shared": [True, False]}
    default_options = {"shared": False}

    def toolchain(self):
        tc = MSBuildToolchain(self)
        tc.write_toolchain_files()

The MSBuildToolchain will generate two files after a conan install command or before calling the build() method when the package is building in the cache:

  • The main conan_toolchain.props file, that can be used in the command line.

  • A conan_toolchain_<config>.props file, that will be conditionally included from the previous conan_toolchain.props file based on the configuration, platform and toolset, e.g.: conan_toolchain_Release_x86_v140.props

Every invocation to conan install with different configuration will create a new properties .props file, that will also be conditionally included. This allows to install different sets of dependencies, then switch among them directly from the Visual Studio IDE.

The toolchain files can configure:

  • The Visual Studio runtime (MT/MD/MTd/MDd), obtained from Conan input settings

  • The C++ standard, obtained from Conan input settings

Generators

The MSBuildToolchain only works with the msbuild generator. Please, do not use other generators, as they can have overlapping definitions that can conflict.

Using the toolchain in developer flow

One of the advantages of using Conan toolchains is that they can help to achieve the exact same build with local development flows, than when the package is created in the cache.

With the MSBuildToolchain it is possible to do:

# Lets start in the folder containing the conanfile.py
$ mkdir build && cd build
# Install both debug and release deps and create the toolchain
$ conan install ..
$ conan install .. -s build_type=Debug
# Add ``conan_toolchain.props`` in your IDE to the project properties
# No need to add the configuration .props files. This needs to be done only once
# If you have dependencies, you will need to add the .props files of the dependencies
# too, check the "msbuild" generator
# Open Visual Studio IDE and build, switching configurations directly in the IDE

MSBuild build helper

When using the toolchain feature, the MSBuild helper that is used in the build() method will be a new, different one with new behavior.

Warning

The new MSBuild helper that is used with toolchains is experimental and subject to breaking changes in the future

The MSBuild helper can be used like:

from conans import ConanFile, MSBuildToolchain, MSBuild

class App(ConanFile):
    settings = "os", "arch", "compiler", "build_type"
    def toolchain(self):
        ...

    def build(self):
        msbuild = MSBuild(self)
        msbuild.build("MyProject.sln")

The MSBuild.build() method internally implements a call to msbuild like:

$ <vcvars-cmd> && msbuild "MyProject.sln" /p:Configuration=<conf> /p:Platform=<platform>

Where:

  • vcvars-cmd is calling the Visual Studio prompt that matches the current recipe settings

  • conf is the configuration, typically Release, Debug, which will be obtained from settings.build_type but this will be configurable. Please open a Github issue if you want to define custom configurations.

  • platform is the architecture, a mapping from the settings.arch to the common β€˜x86’, β€˜x64’, β€˜ARM’, β€˜ARM64’. If your platform is unsupported, please report in Github issues as well: