FindBoost¶
Changed in version 3.30: This module is available only if policy CMP0167 is not set to
NEW.  Port projects to upstream Boost's BoostConfig.cmake package
configuration file, for which find_package(Boost) now searches.
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. 1.67.0
  [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"
  [OPTIONAL_COMPONENTS <libs>...]
                         # Optional 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.
Added in version 3.7: bzip2 and zlib components (Windows only).
Added in version 3.11: The OPTIONAL_COMPONENTS option.
Added in version 3.13: stacktrace_* components.
Added in version 3.19: bzip2 and zlib components on all platforms.
Result Variables¶
This module defines the following 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_<COMPONENT>_FOUND
- True if component - <COMPONENT>was found (- <COMPONENT>name is upper-case).
- Boost_<COMPONENT>_LIBRARY
- Libraries to link for component - <COMPONENT>(may include- target_link_libraries()debug/optimized keywords).
- Boost_VERSION_MACRO
- BOOST_VERSIONvalue from- boost/version.hpp.
- Boost_VERSION_STRING
- Boost version number in - X.Y.Zformat.
- Boost_VERSION
- Boost version number in - X.Y.Zformat (same as- Boost_VERSION_STRING).- Changed in version 3.15: In previous CMake versions, this variable used the raw version string from the Boost header (same as - Boost_VERSION_MACRO). See policy- CMP0093.
- Boost_LIB_VERSION
- Version string appended to library filenames. 
- Boost_VERSION_MAJOR,- Boost_MAJOR_VERSION
- Boost major version number ( - Xin- X.Y.Z).
- Boost_VERSION_MINOR,- Boost_MINOR_VERSION
- Boost minor version number ( - Yin- X.Y.Z).
- Boost_VERSION_PATCH,- Boost_SUBMINOR_VERSION
- Boost subminor version number ( - Zin- X.Y.Z).
- Boost_VERSION_COUNT
- Amount of version components (3). 
- Boost_LIB_DIAGNOSTIC_DEFINITIONS(Windows-specific)
- Pass to - add_definitions()to have diagnostic information about Boost's automatic linking displayed during compilation
Added in version 3.15: The Boost_VERSION_<PART> variables.
Cache variables¶
Search results are saved 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_<COMPONENT>_LIBRARY_DEBUG
- Component - <COMPONENT>library debug variant.
- Boost_<COMPONENT>_LIBRARY_RELEASE
- Component - <COMPONENT>library release variant.
Added in version 3.3: Per-configuration variables Boost_LIBRARY_DIR_RELEASE and
Boost_LIBRARY_DIR_DEBUG.
Hints¶
This module reads hints about search locations from variables:
- BOOST_ROOT,- BOOSTROOT
- Preferred installation prefix. 
- BOOST_INCLUDEDIR
- Preferred include directory e.g. - <prefix>/include.
- BOOST_LIBRARYDIR
- Preferred library directory e.g. - <prefix>/lib.
- Boost_NO_SYSTEM_PATHS
- Set to - ONto 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). 
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_<COMPONENT>_LIBRARY_DEBUG and Boost_<COMPONENT>_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.
Imported Targets¶
Added in version 3.5.
This module defines the following IMPORTED targets:
- Boost::boost
- Target for header-only dependencies. (Boost include directory). 
- Boost::headers
- Added in version 3.15: Alias for - Boost::boost.
- Boost::<component>
- Target for specific component dependency (shared or static library); - <component>name is lower-case.
- Boost::diagnostic_definitions
- Interface target to enable diagnostic information about Boost's automatic linking during compilation (adds - -DBOOST_LIB_DIAGNOSTIC).
- Boost::disable_autolinking
- Interface target to disable automatic linking with MSVC (adds - -DBOOST_ALL_NO_LIB).
- Boost::dynamic_linking
- Interface target to enable dynamic linking with MSVC (adds - -DBOOST_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 Threads::Threads 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.
Other Variables¶
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_DEBUG_LIBS
- Added in version 3.10. - Set to - ONor- OFFto specify whether to search and use the debug libraries. Default is- ON.
- Boost_USE_RELEASE_LIBS
- Added in version 3.10. - Set to - ONor- OFFto specify whether to search and use the release libraries. Default is- ON.
- 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 - ONor- OFFto specify whether to use libraries linked statically to the C++ runtime ("s" tag). Default is platform dependent.
- Boost_USE_DEBUG_RUNTIME
- Set to - ONor- OFFto specify whether to use libraries linked to the MS debug C++ runtime ("g" tag). Default is- ON.
- Boost_USE_DEBUG_PYTHON
- Set to - ONto use libraries compiled with a debug Python build ("y" tag). Default is- OFF.
- Boost_USE_STLPORT
- Set to - ONto 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.- Changed in version 3.9: A list may be used if multiple compatible suffixes should be tested for, in decreasing order of preference. 
- Boost_LIB_PREFIX
- Added in version 3.18. - Set to the platform-specific library name prefix (e.g. - lib) used by Boost static libs. This is needed only on platforms where CMake does not know the prefix by default.
- Boost_ARCHITECTURE
- Added in version 3.13. - Set to the architecture-specific library suffix (e.g. - -x64). Default is auto-computed for the C++ compiler in use.
- Boost_THREADAPI
- Suffix for - threadcomponent library name, such as- pthreador- 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_threadinstead of- boost_thread.
Other variables one may set to control this module are:
- Boost_DEBUG
- Set to - ONto enable debug output from- FindBoost. Please enable this before filing any bug report.
- Boost_REALPATH
- Set to - ONto resolve symlinks for discovered libraries to assist with packaging. For example, the "system" component library may be resolved to- /usr/lib/libboost_system.so.1.67.0instead 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_RELEASEand- Boost_LIBRARY_DIR_DEBUG.
- Boost_NO_WARN_NEW_VERSIONS
- Added in version 3.20. - Set to - ONto suppress the warning about unknown dependencies for new Boost versions.
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(${Boost_LIB_DIAGNOSTIC_DEFINITIONS})
to ask Boost to report information about automatic linking requests.
Examples¶
Find Boost headers only:
find_package(Boost 1.36.0)
if(Boost_FOUND)
  include_directories(${Boost_INCLUDE_DIRS})
  add_executable(foo foo.cc)
endif()
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)
Find Boost Python 3.6 libraries and use imported targets:
find_package(Boost 1.67 REQUIRED COMPONENTS
             python36 numpy36)
add_executable(foo foo.cc)
target_link_libraries(foo Boost::python36 Boost::numpy36)
Find Boost headers and some static (release only) libraries:
set(Boost_USE_STATIC_LIBS        ON)  # only find static libs
set(Boost_USE_DEBUG_LIBS        OFF)  # ignore debug libs and
set(Boost_USE_RELEASE_LIBS       ON)  # only find release libs
set(Boost_USE_MULTITHREADED      ON)
set(Boost_USE_STATIC_RUNTIME    OFF)
find_package(Boost 1.66.0 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 or from Boost 1.70.0 on
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.
