If defined in the environment, this variable will raise errors whenever a Conan 2.0 deprecated feature is used. It is a good mechanism to check the recipes future Conan 2.0 “compliance”. Activating it should not change behavior in any way, just raise error for deprecated things, but if it works, the same result should be achieved. The number of deprecated features will increase in future Conan 1.X releases, it could be a good practice to have it activated in some nightly job or the like, to report on current status of your recipes.
So, if you are ready to experiment add the variable
CONAN_V2_MODE to your
environment and, please, report your feedback about it.
The following is a current known list of features that will change in Conan 2.0 and might start raising errors if CONAN_V2_MODE is activated:
Changes in recipes
These changes could break existing recipes:
Forbid access to
Forbid access to
default_optionsare required to be a dictionary.
Raise if setting
cppstdappears in the recipe.
Deprecate environment variables
PYTHONPATHis not added automatically to the environment before running consumer functions.
self.versionis ensured to be a string in all the functions and scenarios.
Access to member
deps_cpp_infoobjects is forbidden, use
get_name(<generator>)with the name of the generator.
Changes in profiles
Could break existing profiles:
scopessection in profiles.
Package name used by the
pkg_configgenerator uses the same rules as any other generator. Previously, if it was not explicit, it was using lowercase
cpp_info.namewhen it was different from the package name.
compilerare not defined when using build helpers Conan will raise an error.
New compiler detection algorithm is used (e.g. when running
conan profile new <name> --detect). Previously,
<compiler> --versionwas parsed to detect the compiler and its version. Now, using
CONAN_V2_MODE, Conan will try to detect the compiler and its version via compiler’s built-in macro definitions.
More changes will be added, some of them could be reverted and the behavior may
change without further noticing. If you are using
CONAN_V2_MODE, thanks! We
really appreciate your feedback about the future of Conan.