Profiles
Profiles allows users to set a complete configuration set for settings, options, environment variables, and build requirements in a file. They have this structure:
[settings]
setting=value
[options]
MyLib:shared=True
[env]
env_var=value
[build_requires]
tool1/0.1@user/channel
tool2/0.1@user/channel, tool3/0.1@user/channel
*: tool4/0.1@user/channel
Profile can be created with new
option in conan profile. And then edit it later.
$ conan profile new mynewprofile --detect
Profile files can be used with -pr
/--profile
option in many commands like conan install or conan create commands.
$ conan create . demo/testing -pr=myprofile
Profiles can be located in different folders. For example, the default <userhome>/.conan/profiles, and be referenced by absolute or relative path:
$ conan install . --profile /abs/path/to/profile # abs path
$ conan install . --profile ./relpath/to/profile # resolved to current dir
$ conan install . --profile profile # resolved to user/.conan/profiles/profile
Listing existing profiles in the profiles folder can be done like this:
$ conan profile list
default
myprofile1
myprofile2
...
You can also show profile’s content:
$ conan profile show myprofile1
Configuration for profile myprofile1:
[settings]
os=Windows
arch=x86_64
compiler=Visual Studio
compiler.version=15
build_type=Release
[options]
[build_requires]
[env]
Use $PROFILE_DIR
in your profile and it will be replaced with the absolute path to
the directory where the profile file is (this path will contain only forward slashes).
It is useful to declare relative folders:
[env]
PATH=$PROFILE_DIR/dev_tools
Tip
You can manage your profiles and share them using conan config install.
Package settings and env vars
Profiles also support package settings and package environment variables definition, so you can override some settings or environment variables for some specific package:
[settings]
zlib:compiler=clang
zlib:compiler.version=3.5
zlib:compiler.libcxx=libstdc++11
compiler=gcc
compiler.version=4.9
compiler.libcxx=libstdc++11
[env]
zlib:CC=/usr/bin/clang
zlib:CXX=/usr/bin/clang++
Your build tool will locate clang compiler only for the zlib package and gcc (default one) for the rest of your dependency tree.
They accept patterns too, like -s *@myuser/*
, which means that packages that have the username “myuser” will use clang 3.5 as compiler, and gcc otherwise:
[settings]
*@myuser/*:compiler=clang
*@myuser/*:compiler.version=3.5
*@myuser/*:compiler.libcxx=libstdc++11
compiler=gcc
compiler.version=4.9
compiler.libcxx=libstdc++11
Note
If you want to override existing system environment variables, you should use the key=value
syntax. If you need to pre-pend to the
system environment variables you should use the syntax key=[value]
or key=[value1, value2, ...]
. A typical example is the
PATH
environment variable, when you want to add paths to the existing system PATH, not override it, you would use:
[env]
PATH=[/some/path/to/my/tool]
Profile composition
You can specify multiple profiles in the command line. The applied configuration will be the composition of all the profiles applied in the order they are specified.
If, for example, you want to apply a build require, like a cmake
installer to your dependency tree,
it won’t be very practical adding the cmake installer reference, e.g cmake/3.16.3
to all your profiles where you could
need to inject cmake
as a build require.
You can specify both profiles instead:
[build_requires]
cmake/3.16.3
$ conan install . --profile clang --profile cmake_316
Profile includes
You can include other profiles using the include()
statement. The path can be relative to the current profile, absolute, or a profile
name from the default profile location in the local cache.
The include()
statement has to be at the top of the profile file:
[settings]
compiler=gcc
compiler.version=4.9
compiler.libcxx=libstdc++11
include(gcc_49)
[settings]
zlib:compiler=clang
zlib:compiler.version=3.5
zlib:compiler.libcxx=libstdc++11
[env]
zlib:CC=/usr/bin/clang
zlib:CXX=/usr/bin/clang++
Variable declaration
In a profile you can declare variables that will be replaced automatically by Conan before the profile is applied. The variables have to be
declared at the top of the file, after the include()
statements.
include(gcc_49)
CLANG=/usr/bin/clang
[settings]
zlib:compiler=clang
zlib:compiler.version=3.5
zlib:compiler.libcxx=libstdc++11
[env]
zlib:CC=$CLANG/clang
zlib:CXX=$CLANG/clang++
The variables will be inherited too, so you can declare variables in a profile and then include the profile in a different one, all the variables will be available:
GCC_PATH=/my/custom/toolchain/path/
[settings]
compiler=gcc
compiler.version=4.9
compiler.libcxx=libstdc++11
include(gcc_49)
[settings]
zlib:compiler=clang
zlib:compiler.version=3.5
zlib:compiler.libcxx=libstdc++11
[env]
zlib:CC=$GCC_PATH/gcc
zlib:CXX=$GCC_PATH/g++
Build profiles and host profiles
All the commands that take a profile as an argument, from Conan v1.24 are starting to accept two profiles with
command line arguments -pr:h
/--profile:host
and -pr:b
/--profile:build
. If both profiles are
provided, Conan will build a graph with some packages associated with the host
platform and some build
requirements associated to the build
platform. There are two scenarios where this feature is
extremly useful:
Examples
If you are working with Linux and you usually work with gcc compiler, but you have installed clang compiler and want to install some
package for clang
compiler, you could do:
Create a
.conan/profiles/clang
file:
[settings]
compiler=clang
compiler.version=3.5
compiler.libcxx=libstdc++11
[env]
CC=/usr/bin/clang
CXX=/usr/bin/clang++
Execute an install command passing the --profile or -pr parameter:
$ conan install . --profile clang
Without profiles you would have needed to set CC and CXX variables in the environment to point to your clang compiler and use -s parameters to specify the settings:
$ export CC=/usr/bin/clang
$ export CXX=/usr/bin/clang++
$ conan install -s compiler=clang -s compiler.version=3.5 -s compiler.libcxx=libstdc++11
A profile can also be used in conan create and conan info:
$ conan create . demo/testing --profile clang
See also
Check the section Build requirements to read more about its usage in a profile.
Check conan profile and profiles/default for full reference.
Related section: Cross building.