FindBoost

Find Boost include dirs and libraries

Use this module by invoking find_package with the form:

find_package(Boost
  [version] [EXACT]      # Minimum or EXACT version e.g. 1.36.0
  [REQUIRED]             # Fail with error if Boost is not found
  [COMPONENTS <libs>...] # Boost libraries by their canonical name
  )                      # e.g. "date_time" for "libboost_date_time"

This module finds headers and requested component libraries OR a CMake package configuration file provided by a “Boost CMake” build. For the latter case skip to the “Boost CMake” section below. For the former case results are reported in variables:

Boost_FOUND            - True if headers and requested libraries were found
Boost_INCLUDE_DIRS     - Boost include directories
Boost_LIBRARY_DIRS     - Link directories for Boost libraries
Boost_LIBRARIES        - Boost component libraries to be linked
Boost_<C>_FOUND        - True if component <C> was found (<C> is upper-case)
Boost_<C>_LIBRARY      - Libraries to link for component <C> (may include
                         target_link_libraries debug/optimized keywords)
Boost_VERSION          - BOOST_VERSION value from boost/version.hpp
Boost_LIB_VERSION      - Version string appended to library filenames
Boost_MAJOR_VERSION    - Boost major version number (X in X.y.z)
Boost_MINOR_VERSION    - Boost minor version number (Y in x.Y.z)
Boost_SUBMINOR_VERSION - Boost subminor version number (Z in x.y.Z)
Boost_LIB_DIAGNOSTIC_DEFINITIONS (Windows)
                       - Pass to add_definitions() to have diagnostic
                         information about Boost's automatic linking
                         displayed during compilation

This module reads hints about search locations from variables:

BOOST_ROOT             - Preferred installation prefix
 (or BOOSTROOT)
BOOST_INCLUDEDIR       - Preferred include directory e.g. <prefix>/include
BOOST_LIBRARYDIR       - Preferred library directory e.g. <prefix>/lib
Boost_NO_SYSTEM_PATHS  - Set to ON to disable searching in locations not
                         specified by these hint variables. Default is OFF.
Boost_ADDITIONAL_VERSIONS
                       - List of Boost versions not known to this module
                         (Boost install locations may contain the version)

and saves search results persistently in CMake cache entries:

Boost_INCLUDE_DIR         - Directory containing Boost headers
Boost_LIBRARY_DIR_RELEASE - Directory containing release Boost libraries
Boost_LIBRARY_DIR_DEBUG   - Directory containing debug Boost libraries
Boost_<C>_LIBRARY_DEBUG   - Component <C> library debug variant
Boost_<C>_LIBRARY_RELEASE - Component <C> library release variant

The following IMPORTED targets are also defined:

Boost::boost                  - Target for header-only dependencies
                                (Boost include directory)
Boost::<C>                    - Target for specific component dependency
                                (shared or static library); <C> is lower-
                                case
Boost::diagnostic_definitions - interface target to enable diagnostic
                                information about Boost's automatic linking
                                during compilation (adds BOOST_LIB_DIAGNOSTIC)
Boost::disable_autolinking    - interface target to disable automatic
                                linking with MSVC (adds BOOST_ALL_NO_LIB)
Boost::dynamic_linking        - interface target to enable dynamic linking
                                linking with MSVC (adds BOOST_ALL_DYN_LINK)

Implicit dependencies such as Boost::filesystem requiring Boost::system will be automatically detected and satisfied, even if system is not specified when using find_package and if Boost::system is not added to target_link_libraries. If using Boost::thread, then Thread::Thread will also be added automatically.

It is important to note that the imported targets behave differently than variables created by this module: multiple calls to find_package(Boost) in the same directory or sub-directories with different options (e.g. static or shared) will not override the values of the targets created by the first call.

Users may set these hints or results as cache entries. Projects should not read these entries directly but instead use the above result variables. Note that some hint names start in upper-case “BOOST”. One may specify these as environment variables if they are not specified as CMake variables or cache entries.

This module first searches for the Boost header files using the above hint variables (excluding BOOST_LIBRARYDIR) and saves the result in Boost_INCLUDE_DIR. Then it searches for requested component libraries using the above hints (excluding BOOST_INCLUDEDIR and Boost_ADDITIONAL_VERSIONS), “lib” directories near Boost_INCLUDE_DIR, and the library name configuration settings below. It saves the library directories in Boost_LIBRARY_DIR_DEBUG and Boost_LIBRARY_DIR_RELEASE and individual library locations in Boost_<C>_LIBRARY_DEBUG and Boost_<C>_LIBRARY_RELEASE. When one changes settings used by previous searches in the same build tree (excluding environment variables) this module discards previous search results affected by the changes and searches again.

Boost libraries come in many variants encoded in their file name. Users or projects may tell this module which variant to find by setting variables:

Boost_USE_MULTITHREADED  - Set to OFF to use the non-multithreaded
                           libraries ('mt' tag).  Default is ON.
Boost_USE_STATIC_LIBS    - Set to ON to force the use of the static
                           libraries.  Default is OFF.
Boost_USE_STATIC_RUNTIME - Set to ON or OFF to specify whether to use
                           libraries linked statically to the C++ runtime
                           ('s' tag).  Default is platform dependent.
Boost_USE_DEBUG_RUNTIME  - Set to ON or OFF to specify whether to use
                           libraries linked to the MS debug C++ runtime
                           ('g' tag).  Default is ON.
Boost_USE_DEBUG_PYTHON   - Set to ON to use libraries compiled with a
                           debug Python build ('y' tag). Default is OFF.
Boost_USE_STLPORT        - Set to ON to use libraries compiled with
                           STLPort ('p' tag).  Default is OFF.
Boost_USE_STLPORT_DEPRECATED_NATIVE_IOSTREAMS
                         - Set to ON to use libraries compiled with
                           STLPort deprecated "native iostreams"
                           ('n' tag).  Default is OFF.
Boost_COMPILER           - Set to the compiler-specific library suffix
                           (e.g. "-gcc43").  Default is auto-computed
                           for the C++ compiler in use.
Boost_THREADAPI          - Suffix for "thread" component library name,
                           such as "pthread" or "win32".  Names with
                           and without this suffix will both be tried.
Boost_NAMESPACE          - Alternate namespace used to build boost with
                           e.g. if set to "myboost", will search for
                           myboost_thread instead of boost_thread.

Other variables one may set to control this module are:

Boost_DEBUG              - Set to ON to enable debug output from FindBoost.
                           Please enable this before filing any bug report.
Boost_DETAILED_FAILURE_MSG
                         - Set to ON to add detailed information to the
                           failure message even when the REQUIRED option
                           is not given to the find_package call.
Boost_REALPATH           - Set to ON to resolve symlinks for discovered
                           libraries to assist with packaging.  For example,
                           the "system" component library may be resolved to
                           "/usr/lib/libboost_system.so.1.42.0" instead of
                           "/usr/lib/libboost_system.so".  This does not
                           affect linking and should not be enabled unless
                           the user needs this information.
Boost_LIBRARY_DIR        - Default value for Boost_LIBRARY_DIR_RELEASE and
                           Boost_LIBRARY_DIR_DEBUG.

On Visual Studio and Borland compilers Boost headers request automatic linking to corresponding libraries. This requires matching libraries to be linked explicitly or available in the link library search path. In this case setting Boost_USE_STATIC_LIBS to OFF may not achieve dynamic linking. Boost automatic linking typically requests static libraries with a few exceptions (such as Boost.Python). Use:

add_definitions(${Boost_LIB_DIAGNOSTIC_DEFINITIONS})

to ask Boost to report information about automatic linking requests.

Example to find Boost headers only:

find_package(Boost 1.36.0)
if(Boost_FOUND)
  include_directories(${Boost_INCLUDE_DIRS})
  add_executable(foo foo.cc)
endif()

Example to find Boost libraries and use imported targets:

find_package(Boost 1.56 REQUIRED COMPONENTS
             date_time filesystem iostreams)
add_executable(foo foo.cc)
target_link_libraries(foo Boost::date_time Boost::filesystem
                          Boost::iostreams)

Example to find Boost headers and some static libraries:

set(Boost_USE_STATIC_LIBS        ON) # only find static libs
set(Boost_USE_MULTITHREADED      ON)
set(Boost_USE_STATIC_RUNTIME    OFF)
find_package(Boost 1.36.0 COMPONENTS date_time filesystem system ...)
if(Boost_FOUND)
  include_directories(${Boost_INCLUDE_DIRS})
  add_executable(foo foo.cc)
  target_link_libraries(foo ${Boost_LIBRARIES})
endif()

Boost CMake

If Boost was built using the boost-cmake project it provides a package configuration file for use with find_package’s Config mode. This module looks for the package configuration file called BoostConfig.cmake or boost-config.cmake and stores the result in cache entry “Boost_DIR”. If found, the package configuration file is loaded and this module returns with no further action. See documentation of the Boost CMake package configuration for details on what it provides.

Set Boost_NO_BOOST_CMAKE to ON to disable the search for boost-cmake.