Upgrading to Conan 1.0

If you have been using a 0.X version of Conan, there are some things to consider when upgrading to version 1.0. These are reflected in the changelog. This section summarizes the most important considerations:

Command line changes

There are quite a few things that will break existing usage (compared to 0.30). Most of these are in command line arguments, so they are relatively easy to fix. The most important one is that now, most commands require the path to the conanfile folder or file, instead of using --path and --file arguments. Specifically, conan install, conan export and conan create are the ones most affected:

# instead of --path=myfolder --file=myconanfile.py, now you can do:
$ conan install . # Note the "." is now mandatory
$ conan install folder/myconanfile.txt
$ conan install ../myconanfile.py
$ conan info .
$ conan create . user/channel
$ conan create . Pkg/0.1@user/channel
$ conan create mypkgconanfile.py Pkg/0.1@user/channel
$ conan export . user/channel
$ conan export . Pkg/0.1@user/channel
$ conan export myfolder/myconanfile.py Pkg/0.1@user/channel

This behavior aligns with the conan source, conan build and conan package commands, that all use the same arguments to locate the conanfile.py containing the logic to be run.

Now all commands read: command <origin-conanfile> ...

Also, all arguments to the command line now use a dash instead of an underscore:

$ conan build .. --source-folder=../src  # not --source_folder

Deprecations/removals

  • Scopes were completely removed in conan 0.30.X

  • self.conanfile_directory has been removed. Use self.source_folder, self.build_folder, etc. instead

  • self.cpp_info, self.env_info and self.user_info scope has been reduced to only the package_info() method

  • gcc and ConfigureEnvironment were already removed in conan 0.30.1

  • werror doesn’t exist anymore. It is now built-in behavior.

  • Command test_package has been removed. Use conan create and conan test instead.

  • CMake helper now (from conan 0.29) only allows the CMake(self) syntax

  • conan package_files command was replaced in conan 0.28 by conan export-pkg command.

Settings and profiles. GCC/Clang versioning

GCC and Clang compilers have modified their versioning approach, from GCC > 5 and Clang > 4. The minor versions are really bugfixes, and then they have binary compatibility. To adapt to this, conan now includes the major version in the settings.yml default settings file:

gcc:
    version: ["4.1", "4.4", "4.5", "4.6", "4.7", "4.8", "4.9",
              "5", "5.1", "5.2", "5.3", "5.4",
              "6", "6.1", "6.2", "6.3", "6.4",
              "7", "7.1", "7.2"]

Most package creators want to use the major-only settings, such as -s compiler=gcc -s compiler.version=5, instead of also specifying the minor versions.

The default profile detection and creation has been modified accordingly, but if you have a default profile, you may want to update it to reflect this:

Conan-associated tools (conan-package-tools, conan.cmake) have been upgraded to accommodate these new defaults.

New features

  • Cross-compilation support with new default settings in settings.yml: os_build, arch_build, os_target, arch_target. They are automatically removed from the package_id computation, or kept if they are the only ones defined (as usually happens with dev-tools packages). It is also possible to keep them with the self.info.include_build_settings() method (call it from your package_id() method).

Important

Please don’t use cross-build settings os_build, arch_build for standard packages and libraries. They are only useful for packages that are used via build_requires, like cmake or mingw_installer.

  • Model and utilities for Windows subsystems

os:
    Windows:
        subsystem: [None, cygwin, msys, msys2, wsl]

This subsetting can be used by build helpers such as CMake to act accordingly.