Rules ForeignCc

Rules for building C/C++ projects using foreign build systems (non Bazel) inside Bazel projects.

Overview

Rules ForeignCc is designed to help users build projects that are not built by Bazel and also not fully under their control (ie: large and mature open source software). These rules provide a mechanism to build these external projects within Bazel's sandbox environment using a variety of C/C++ build systems to be later consumed by other rules as though they were normal cc rules.

Setup

To use the ForeignCc build rules, add the following content to your WORKSPACE file:

load("@bazel_tools//tools/build_defs/repo:http.bzl", "http_archive")

http_archive(
    name = "rules_foreign_cc",
    # TODO: Get the latest sha256 value from the latest release on the releases page
    #       https://github.com/bazelbuild/rules_foreign_cc/releases
    #
    # sha256 = "...",
    strip_prefix = "rules_foreign_cc-0.3.0",
    url = "https://github.com/bazelbuild/rules_foreign_cc/archive/0.3.0.tar.gz",
)

load("@rules_foreign_cc//foreign_cc:repositories.bzl", "rules_foreign_cc_dependencies")

rules_foreign_cc_dependencies()

Please note that there are many different configuration options for rules_foreign_cc_dependencies which offer more control over the toolchains used during the build phase. Please see that macro's documentation for more details.

Rules

For additional rules/macros/providers, see the full API in one page.

CMake

Building CMake projects

  • Build libraries/binaries with CMake from sources using cmake rule
  • Use cmake targets in cc_library, cc_binary targets as dependency
  • Bazel cc_toolchain parameters are used inside cmake build
  • See full list of cmake arguments below 'example'
  • cmake is defined in ./tools/build_defs
  • Works on Ubuntu, Mac OS and Windows(* see special notes below in Windows section) operating systems

Example: (Please see full examples in ./examples)

The example for Windows is below, in the section 'Usage on Windows'.

  • In WORKSPACE.bazel, we use a http_archive to download tarballs with the libraries we use.
  • In BUILD.bazel, we instantiate a cmake rule which behaves similarly to a cc_library, which can then be used in a C++ rule (cc_binary in this case).

In WORKSPACE.bazel, put

workspace(name = "rules_foreign_cc_usage_example")

load("@bazel_tools//tools/build_defs/repo:http.bzl", "http_archive")

# Rule repository, note that it's recommended to use a pinned commit to a released version of the rules
http_archive(
   name = "rules_foreign_cc",
   sha256 = "c2cdcf55ffaf49366725639e45dedd449b8c3fe22b54e31625eb80ce3a240f1e",
   strip_prefix = "rules_foreign_cc-0.1.0",
   url = "https://github.com/bazelbuild/rules_foreign_cc/archive/0.1.0.zip",
)

load("@rules_foreign_cc//foreign_cc:repositories.bzl", "rules_foreign_cc_dependencies")

# This sets up some common toolchains for building targets. For more details, please see
# https://github.com/bazelbuild/rules_foreign_cc/tree/main/docs#rules_foreign_cc_dependencies
rules_foreign_cc_dependencies()

_ALL_CONTENT = """\
filegroup(
    name = "all_srcs",
    srcs = glob(["**"]),
    visibility = ["//visibility:public"],
)
"""

# pcre source code repository
http_archive(
    name = "pcre",
    build_file_content = _ALL_CONTENT,
    strip_prefix = "pcre-8.43",
    urls = [
        "https://mirror.bazel.build/ftp.pcre.org/pub/pcre/pcre-8.43.tar.gz",
        "https://ftp.pcre.org/pub/pcre/pcre-8.43.tar.gz",
    ],
    sha256 = "0b8e7465dc5e98c757cc3650a20a7843ee4c3edf50aaf60bb33fd879690d2c73",
)

And in the BUILD.bazel file, put:

load("@rules_foreign_cc//foreign_cc:defs.bzl", "cmake")

cmake(
    name = "pcre",
    cache_entries = {
        "CMAKE_C_FLAGS": "-fPIC",
    },
    lib_source = "@pcre//:all_srcs",
    out_static_libs = ["libpcre.a"],
)

then build as usual:

bazel build //:pcre

Usage on Windows

When using on Windows, you should start Bazel in MSYS2 shell, as the shell script inside cmake assumes this. Also, you should explicitly specify make commands and option to generate CMake crosstool file.

The default generator for CMake will be detected automatically, or you can specify it explicitly.

The tested generators: Visual Studio 15, Ninja and NMake. The extension .lib is assumed for the static libraries by default.

Example usage (see full example in ./examples/cmake_hello_world_lib): Example assumes that MS Visual Studio and Ninja are installed on the host machine, and Ninja bin directory is added to PATH.

cmake(
    # expect to find ./lib/hello.lib as the result of the build
    name = "hello",
    # This option can be omitted
    generate_args = [
        "-G \"Visual Studio 15 2017\"",
        "-A Win64",
    ],
    lib_source = ":srcs",
)

cmake(
    name = "hello_ninja",
    # expect to find ./lib/hello.lib as the result of the build
    lib_name = "hello",
    # explicitly specify the generator
    generate_args = ["-GNinja"],
    lib_source = ":srcs",
)

cmake(
    name = "hello_nmake",
    # explicitly specify the generator
    generate_args = ["-G \"NMake Makefiles\""],
    lib_source = ":srcs",
    # expect to find ./lib/hello.lib as the result of the build
    out_static_libs = ["hello.lib"],
)

cmake

cmake(name, additional_inputs, additional_tools, alwayslink, build_args, cache_entries, data,
      defines, deps, env, env_vars, generate_args, generate_crosstool_file, install, install_args,
      lib_name, lib_source, linkopts, out_bin_dir, out_binaries, out_headers_only, out_include_dir,
      out_interface_libs, out_lib_dir, out_shared_libs, out_static_libs, postfix_script, targets,
      tools_deps, working_directory)

Rule for building external library with CMake.

ATTRIBUTES

NameDescriptionTypeMandatoryDefault
nameA unique name for this target.Namerequired
additional_inputsOptional additional inputs to be declared as needed for the shell script action.Not used by the shell script part in cc_external_rule_impl.List of labelsoptional[]
additional_toolsOptional additional tools needed for the building. Not used by the shell script part in cc_external_rule_impl.List of labelsoptional[]
alwayslinkOptional. if true, link all the object files from the static library, even if they are not used.BooleanoptionalFalse
build_argsArguments for the CMake build commandList of stringsoptional[]
cache_entriesCMake cache entries to initialize (they will be passed with -Dkey=value) Values, defined by the toolchain, will be joined with the values, passed here. (Toolchain values come first)Dictionary: String -> Stringoptional{}
dataFiles needed by this rule at runtime. May list file or rule targets. Generally allows any target.List of labelsoptional[]
definesOptional compilation definitions to be passed to the dependencies of this library. They are NOT passed to the compiler, you should duplicate them in the configuration options.List of stringsoptional[]
depsOptional dependencies to be copied into the directory structure. Typically those directly required for the external building of the library/binaries. (i.e. those that the external buidl system will be looking for and paths to which are provided by the calling rule)List of labelsoptional[]
envEnvironment variables to set during the build. $(execpath) macros may be used to point at files which are listed as data deps, tools_deps, or additional_tools, but unlike with other rules, these will be replaced with absolute paths to those files, because the build does not run in the exec root. No other macros are supported.Dictionary: String -> Stringoptional{}
env_varsCMake environment variable values to join with toolchain-defined. For example, additional CXXFLAGS.Dictionary: String -> Stringoptional{}
generate_argsArguments for CMake's generate command. Arguments should be passed as key/value pairs. eg: ["-G Ninja", "--debug-output", "-DFOO=bar"]. Note that unless a generator (-G) argument is provided, the default generators are Unix Makefiles for Linux and MacOS and Ninja for Windows.List of stringsoptional[]
generate_crosstool_fileWhen True, CMake crosstool file will be generated from the toolchain values, provided cache-entries and env_vars (some values will still be passed as -Dkey=value and environment variables). If CMAKE_TOOLCHAIN_FILE cache entry is passed, specified crosstool file will be used When using this option to cross-compile, it is required to specify CMAKE_SYSTEM_NAME in the cache_entriesBooleanoptionalTrue
installIf True, the cmake --install comand will be performed after a buildBooleanoptionalTrue
install_argsArguments for the CMake install commandList of stringsoptional[]
lib_nameLibrary name. Defines the name of the install directory and the name of the static library, if no output files parameters are defined (any of static_libraries, shared_libraries, interface_libraries, binaries_names) Optional. If not defined, defaults to the target's name.Stringoptional""
lib_sourceLabel with source code to build. Typically a filegroup for the source of remote repository. Mandatory.Labelrequired
linkoptsOptional link options to be passed up to the dependencies of this libraryList of stringsoptional[]
out_bin_dirOptional name of the output subdirectory with the binary files, defaults to 'bin'.Stringoptional"bin"
out_binariesOptional names of the resulting binaries.List of stringsoptional[]
out_headers_onlyFlag variable to indicate that the library produces only headersBooleanoptionalFalse
out_include_dirOptional name of the output subdirectory with the header files, defaults to 'include'.Stringoptional"include"
out_interface_libsOptional names of the resulting interface libraries.List of stringsoptional[]
out_lib_dirOptional name of the output subdirectory with the library files, defaults to 'lib'.Stringoptional"lib"
out_shared_libsOptional names of the resulting shared libraries.List of stringsoptional[]
out_static_libsOptional names of the resulting static libraries. Note that if out_headers_only, out_static_libs, out_shared_libs, and out_binaries are not set, default lib_name.a/lib_name.lib static library is assumedList of stringsoptional[]
postfix_scriptOptional part of the shell script to be added after the make commandsStringoptional""
targetsA list of targets with in the foreign build system to produce. An empty string ("") will result in a call to the underlying build system with no explicit target setList of stringsoptional[]
tools_depsOptional tools to be copied into the directory structure. Similar to deps, those directly required for the external building of the library/binaries.List of labelsoptional[]
working_directoryWorking directory, with the main CMakeLists.txt (otherwise, the top directory of the lib_source label files is used.)Stringoptional""

A rule for building projects using the[Configure+Make][cm] build tool [cm]: https://www.gnu.org/prep/standards/html_node/Configuration.html

configure_make

configure_make(name, additional_inputs, additional_tools, alwayslink, args, autoconf,
               autoconf_env_vars, autoconf_options, autogen, autogen_command, autogen_env_vars,
               autogen_options, autoreconf, autoreconf_env_vars, autoreconf_options,
               configure_command, configure_env_vars, configure_in_place, configure_options, data,
               defines, deps, env, install_prefix, lib_name, lib_source, linkopts, make_commands,
               out_bin_dir, out_binaries, out_headers_only, out_include_dir, out_interface_libs,
               out_lib_dir, out_shared_libs, out_static_libs, postfix_script, targets, tools_deps)

Rule for building external libraries with configure-make pattern. Some 'configure' script is invoked with --prefix=install (by default), and other parameters for compilation and linking, taken from Bazel C/C++ toolchain and passed dependencies. After configuration, GNU Make is called.

ATTRIBUTES

NameDescriptionTypeMandatoryDefault
nameA unique name for this target.Namerequired
additional_inputsOptional additional inputs to be declared as needed for the shell script action.Not used by the shell script part in cc_external_rule_impl.List of labelsoptional[]
additional_toolsOptional additional tools needed for the building. Not used by the shell script part in cc_external_rule_impl.List of labelsoptional[]
alwayslinkOptional. if true, link all the object files from the static library, even if they are not used.BooleanoptionalFalse
argsA list of arguments to pass to the call to makeList of stringsoptional[]
autoconfSet to True if 'autoconf' should be invoked before 'configure', currently requires configure_in_place to be True.BooleanoptionalFalse
autoconf_env_varsEnvironment variables to be set for 'autoconf' invocation.Dictionary: String -> Stringoptional{}
autoconf_optionsAny options to be put in the 'autoconf.sh' command line.List of stringsoptional[]
autogenSet to True if 'autogen.sh' should be invoked before 'configure', currently requires configure_in_place to be True.BooleanoptionalFalse
autogen_commandThe name of the autogen script file, default: autogen.sh. Many projects use autogen.sh however the Autotools FAQ recommends bootstrap so we provide this option to support that.Stringoptional"autogen.sh"
autogen_env_varsEnvironment variables to be set for 'autogen' invocation.Dictionary: String -> Stringoptional{}
autogen_optionsAny options to be put in the 'autogen.sh' command line.List of stringsoptional[]
autoreconfSet to True if 'autoreconf' should be invoked before 'configure.', currently requires configure_in_place to be True.BooleanoptionalFalse
autoreconf_env_varsEnvironment variables to be set for 'autoreconf' invocation.Dictionary: String -> Stringoptional{}
autoreconf_optionsAny options to be put in the 'autoreconf.sh' command line.List of stringsoptional[]
configure_commandThe name of the configuration script file, default: configure. The file must be in the root of the source directory.Stringoptional"configure"
configure_env_varsEnvironment variables to be set for the 'configure' invocation.Dictionary: String -> Stringoptional{}
configure_in_placeSet to True if 'configure' should be invoked in place, i.e. from its enclosing directory.BooleanoptionalFalse
configure_optionsAny options to be put on the 'configure' command line.List of stringsoptional[]
dataFiles needed by this rule at runtime. May list file or rule targets. Generally allows any target.List of labelsoptional[]
definesOptional compilation definitions to be passed to the dependencies of this library. They are NOT passed to the compiler, you should duplicate them in the configuration options.List of stringsoptional[]
depsOptional dependencies to be copied into the directory structure. Typically those directly required for the external building of the library/binaries. (i.e. those that the external buidl system will be looking for and paths to which are provided by the calling rule)List of labelsoptional[]
envEnvironment variables to set during the build. $(execpath) macros may be used to point at files which are listed as data deps, tools_deps, or additional_tools, but unlike with other rules, these will be replaced with absolute paths to those files, because the build does not run in the exec root. No other macros are supported.Dictionary: String -> Stringoptional{}
install_prefixInstall prefix, i.e. relative path to where to install the result of the build. Passed to the 'configure' script with --prefix flag.Stringoptional""
lib_nameLibrary name. Defines the name of the install directory and the name of the static library, if no output files parameters are defined (any of static_libraries, shared_libraries, interface_libraries, binaries_names) Optional. If not defined, defaults to the target's name.Stringoptional""
lib_sourceLabel with source code to build. Typically a filegroup for the source of remote repository. Mandatory.Labelrequired
linkoptsOptional link options to be passed up to the dependencies of this libraryList of stringsoptional[]
make_commandsOptional make commands.List of stringsoptional["make", "make install"]
out_bin_dirOptional name of the output subdirectory with the binary files, defaults to 'bin'.Stringoptional"bin"
out_binariesOptional names of the resulting binaries.List of stringsoptional[]
out_headers_onlyFlag variable to indicate that the library produces only headersBooleanoptionalFalse
out_include_dirOptional name of the output subdirectory with the header files, defaults to 'include'.Stringoptional"include"
out_interface_libsOptional names of the resulting interface libraries.List of stringsoptional[]
out_lib_dirOptional name of the output subdirectory with the library files, defaults to 'lib'.Stringoptional"lib"
out_shared_libsOptional names of the resulting shared libraries.List of stringsoptional[]
out_static_libsOptional names of the resulting static libraries. Note that if out_headers_only, out_static_libs, out_shared_libs, and out_binaries are not set, default lib_name.a/lib_name.lib static library is assumedList of stringsoptional[]
postfix_scriptOptional part of the shell script to be added after the make commandsStringoptional""
targetsA list of targets within the foreign build system to produce. An empty string ("") will result in a call to the underlying build system with no explicit target setList of stringsoptional["", "install"]
tools_depsOptional tools to be copied into the directory structure. Similar to deps, those directly required for the external building of the library/binaries.List of labelsoptional[]

A rule for building projects using the GNU Make build tool

make

make(name, additional_inputs, additional_tools, alwayslink, args, data, defines, deps, env,
     lib_name, lib_source, linkopts, out_bin_dir, out_binaries, out_headers_only, out_include_dir,
     out_interface_libs, out_lib_dir, out_shared_libs, out_static_libs, postfix_script, targets,
     tools_deps)

Rule for building external libraries with GNU Make. GNU Make commands (make and make install by default) are invoked with prefix="install" (by default), and other environment variables for compilation and linking, taken from Bazel C/C++ toolchain and passed dependencies.

ATTRIBUTES

NameDescriptionTypeMandatoryDefault
nameA unique name for this target.Namerequired
additional_inputsOptional additional inputs to be declared as needed for the shell script action.Not used by the shell script part in cc_external_rule_impl.List of labelsoptional[]
additional_toolsOptional additional tools needed for the building. Not used by the shell script part in cc_external_rule_impl.List of labelsoptional[]
alwayslinkOptional. if true, link all the object files from the static library, even if they are not used.BooleanoptionalFalse
argsA list of arguments to pass to the call to makeList of stringsoptional[]
dataFiles needed by this rule at runtime. May list file or rule targets. Generally allows any target.List of labelsoptional[]
definesOptional compilation definitions to be passed to the dependencies of this library. They are NOT passed to the compiler, you should duplicate them in the configuration options.List of stringsoptional[]
depsOptional dependencies to be copied into the directory structure. Typically those directly required for the external building of the library/binaries. (i.e. those that the external buidl system will be looking for and paths to which are provided by the calling rule)List of labelsoptional[]
envEnvironment variables to set during the build. $(execpath) macros may be used to point at files which are listed as data deps, tools_deps, or additional_tools, but unlike with other rules, these will be replaced with absolute paths to those files, because the build does not run in the exec root. No other macros are supported.Dictionary: String -> Stringoptional{}
lib_nameLibrary name. Defines the name of the install directory and the name of the static library, if no output files parameters are defined (any of static_libraries, shared_libraries, interface_libraries, binaries_names) Optional. If not defined, defaults to the target's name.Stringoptional""
lib_sourceLabel with source code to build. Typically a filegroup for the source of remote repository. Mandatory.Labelrequired
linkoptsOptional link options to be passed up to the dependencies of this libraryList of stringsoptional[]
out_bin_dirOptional name of the output subdirectory with the binary files, defaults to 'bin'.Stringoptional"bin"
out_binariesOptional names of the resulting binaries.List of stringsoptional[]
out_headers_onlyFlag variable to indicate that the library produces only headersBooleanoptionalFalse
out_include_dirOptional name of the output subdirectory with the header files, defaults to 'include'.Stringoptional"include"
out_interface_libsOptional names of the resulting interface libraries.List of stringsoptional[]
out_lib_dirOptional name of the output subdirectory with the library files, defaults to 'lib'.Stringoptional"lib"
out_shared_libsOptional names of the resulting shared libraries.List of stringsoptional[]
out_static_libsOptional names of the resulting static libraries. Note that if out_headers_only, out_static_libs, out_shared_libs, and out_binaries are not set, default lib_name.a/lib_name.lib static library is assumedList of stringsoptional[]
postfix_scriptOptional part of the shell script to be added after the make commandsStringoptional""
targetsA list of targets within the foreign build system to produce. An empty string ("") will result in a call to the underlying build system with no explicit target setList of stringsoptional["", "install"]
tools_depsOptional tools to be copied into the directory structure. Similar to deps, those directly required for the external building of the library/binaries.List of labelsoptional[]

A rule for building projects using the Ninja build tool

ninja

ninja(name, additional_inputs, additional_tools, alwayslink, args, data, defines, deps, directory,
      env, lib_name, lib_source, linkopts, out_bin_dir, out_binaries, out_headers_only,
      out_include_dir, out_interface_libs, out_lib_dir, out_shared_libs, out_static_libs,
      postfix_script, targets, tools_deps)

Rule for building external libraries with Ninja.

ATTRIBUTES

NameDescriptionTypeMandatoryDefault
nameA unique name for this target.Namerequired
additional_inputsOptional additional inputs to be declared as needed for the shell script action.Not used by the shell script part in cc_external_rule_impl.List of labelsoptional[]
additional_toolsOptional additional tools needed for the building. Not used by the shell script part in cc_external_rule_impl.List of labelsoptional[]
alwayslinkOptional. if true, link all the object files from the static library, even if they are not used.BooleanoptionalFalse
argsA list of arguments to pass to the call to ninjaList of stringsoptional[]
dataFiles needed by this rule at runtime. May list file or rule targets. Generally allows any target.List of labelsoptional[]
definesOptional compilation definitions to be passed to the dependencies of this library. They are NOT passed to the compiler, you should duplicate them in the configuration options.List of stringsoptional[]
depsOptional dependencies to be copied into the directory structure. Typically those directly required for the external building of the library/binaries. (i.e. those that the external buidl system will be looking for and paths to which are provided by the calling rule)List of labelsoptional[]
directoryA directory to pass as the -C argument. The rule will always use the root directory of the lib_sources attribute if this attribute is not setStringoptional""
envEnvironment variables to set during the build. $(execpath) macros may be used to point at files which are listed as data deps, tools_deps, or additional_tools, but unlike with other rules, these will be replaced with absolute paths to those files, because the build does not run in the exec root. No other macros are supported.Dictionary: String -> Stringoptional{}
lib_nameLibrary name. Defines the name of the install directory and the name of the static library, if no output files parameters are defined (any of static_libraries, shared_libraries, interface_libraries, binaries_names) Optional. If not defined, defaults to the target's name.Stringoptional""
lib_sourceLabel with source code to build. Typically a filegroup for the source of remote repository. Mandatory.Labelrequired
linkoptsOptional link options to be passed up to the dependencies of this libraryList of stringsoptional[]
out_bin_dirOptional name of the output subdirectory with the binary files, defaults to 'bin'.Stringoptional"bin"
out_binariesOptional names of the resulting binaries.List of stringsoptional[]
out_headers_onlyFlag variable to indicate that the library produces only headersBooleanoptionalFalse
out_include_dirOptional name of the output subdirectory with the header files, defaults to 'include'.Stringoptional"include"
out_interface_libsOptional names of the resulting interface libraries.List of stringsoptional[]
out_lib_dirOptional name of the output subdirectory with the library files, defaults to 'lib'.Stringoptional"lib"
out_shared_libsOptional names of the resulting shared libraries.List of stringsoptional[]
out_static_libsOptional names of the resulting static libraries. Note that if out_headers_only, out_static_libs, out_shared_libs, and out_binaries are not set, default lib_name.a/lib_name.lib static library is assumedList of stringsoptional[]
postfix_scriptOptional part of the shell script to be added after the make commandsStringoptional""
targetsA list of targets with in the foreign build system to produce. An empty string ("") will result in a call to the underlying build system with no explicit target setList of stringsoptional[]
tools_depsOptional tools to be copied into the directory structure. Similar to deps, those directly required for the external building of the library/binaries.List of labelsoptional[]

Rules Foreign CC

boost_build

boost_build(name, additional_inputs, additional_tools, alwayslink, bootstrap_options, data, defines,
            deps, env, lib_name, lib_source, linkopts, out_bin_dir, out_binaries, out_headers_only,
            out_include_dir, out_interface_libs, out_lib_dir, out_shared_libs, out_static_libs,
            postfix_script, tools_deps, user_options)

Rule for building Boost. Invokes bootstrap.sh and then b2 install.

ATTRIBUTES

NameDescriptionTypeMandatoryDefault
nameA unique name for this target.Namerequired
additional_inputsOptional additional inputs to be declared as needed for the shell script action.Not used by the shell script part in cc_external_rule_impl.List of labelsoptional[]
additional_toolsOptional additional tools needed for the building. Not used by the shell script part in cc_external_rule_impl.List of labelsoptional[]
alwayslinkOptional. if true, link all the object files from the static library, even if they are not used.BooleanoptionalFalse
bootstrap_optionsany additional flags to pass to bootstrap.shList of stringsoptional[]
dataFiles needed by this rule at runtime. May list file or rule targets. Generally allows any target.List of labelsoptional[]
definesOptional compilation definitions to be passed to the dependencies of this library. They are NOT passed to the compiler, you should duplicate them in the configuration options.List of stringsoptional[]
depsOptional dependencies to be copied into the directory structure. Typically those directly required for the external building of the library/binaries. (i.e. those that the external buidl system will be looking for and paths to which are provided by the calling rule)List of labelsoptional[]
envEnvironment variables to set during the build. $(execpath) macros may be used to point at files which are listed as data deps, tools_deps, or additional_tools, but unlike with other rules, these will be replaced with absolute paths to those files, because the build does not run in the exec root. No other macros are supported.Dictionary: String -> Stringoptional{}
lib_nameLibrary name. Defines the name of the install directory and the name of the static library, if no output files parameters are defined (any of static_libraries, shared_libraries, interface_libraries, binaries_names) Optional. If not defined, defaults to the target's name.Stringoptional""
lib_sourceLabel with source code to build. Typically a filegroup for the source of remote repository. Mandatory.Labelrequired
linkoptsOptional link options to be passed up to the dependencies of this libraryList of stringsoptional[]
out_bin_dirOptional name of the output subdirectory with the binary files, defaults to 'bin'.Stringoptional"bin"
out_binariesOptional names of the resulting binaries.List of stringsoptional[]
out_headers_onlyFlag variable to indicate that the library produces only headersBooleanoptionalFalse
out_include_dirOptional name of the output subdirectory with the header files, defaults to 'include'.Stringoptional"include"
out_interface_libsOptional names of the resulting interface libraries.List of stringsoptional[]
out_lib_dirOptional name of the output subdirectory with the library files, defaults to 'lib'.Stringoptional"lib"
out_shared_libsOptional names of the resulting shared libraries.List of stringsoptional[]
out_static_libsOptional names of the resulting static libraries. Note that if out_headers_only, out_static_libs, out_shared_libs, and out_binaries are not set, default lib_name.a/lib_name.lib static library is assumedList of stringsoptional[]
postfix_scriptOptional part of the shell script to be added after the make commandsStringoptional""
tools_depsOptional tools to be copied into the directory structure. Similar to deps, those directly required for the external building of the library/binaries.List of labelsoptional[]
user_optionsany additional flags to pass to b2List of stringsoptional[]

cmake

cmake(name, additional_inputs, additional_tools, alwayslink, build_args, cache_entries, data,
      defines, deps, env, env_vars, generate_args, generate_crosstool_file, install, install_args,
      lib_name, lib_source, linkopts, out_bin_dir, out_binaries, out_headers_only, out_include_dir,
      out_interface_libs, out_lib_dir, out_shared_libs, out_static_libs, postfix_script, targets,
      tools_deps, working_directory)

Rule for building external library with CMake.

ATTRIBUTES

NameDescriptionTypeMandatoryDefault
nameA unique name for this target.Namerequired
additional_inputsOptional additional inputs to be declared as needed for the shell script action.Not used by the shell script part in cc_external_rule_impl.List of labelsoptional[]
additional_toolsOptional additional tools needed for the building. Not used by the shell script part in cc_external_rule_impl.List of labelsoptional[]
alwayslinkOptional. if true, link all the object files from the static library, even if they are not used.BooleanoptionalFalse
build_argsArguments for the CMake build commandList of stringsoptional[]
cache_entriesCMake cache entries to initialize (they will be passed with -Dkey=value) Values, defined by the toolchain, will be joined with the values, passed here. (Toolchain values come first)Dictionary: String -> Stringoptional{}
dataFiles needed by this rule at runtime. May list file or rule targets. Generally allows any target.List of labelsoptional[]
definesOptional compilation definitions to be passed to the dependencies of this library. They are NOT passed to the compiler, you should duplicate them in the configuration options.List of stringsoptional[]
depsOptional dependencies to be copied into the directory structure. Typically those directly required for the external building of the library/binaries. (i.e. those that the external buidl system will be looking for and paths to which are provided by the calling rule)List of labelsoptional[]
envEnvironment variables to set during the build. $(execpath) macros may be used to point at files which are listed as data deps, tools_deps, or additional_tools, but unlike with other rules, these will be replaced with absolute paths to those files, because the build does not run in the exec root. No other macros are supported.Dictionary: String -> Stringoptional{}
env_varsCMake environment variable values to join with toolchain-defined. For example, additional CXXFLAGS.Dictionary: String -> Stringoptional{}
generate_argsArguments for CMake's generate command. Arguments should be passed as key/value pairs. eg: ["-G Ninja", "--debug-output", "-DFOO=bar"]. Note that unless a generator (-G) argument is provided, the default generators are Unix Makefiles for Linux and MacOS and Ninja for Windows.List of stringsoptional[]
generate_crosstool_fileWhen True, CMake crosstool file will be generated from the toolchain values, provided cache-entries and env_vars (some values will still be passed as -Dkey=value and environment variables). If CMAKE_TOOLCHAIN_FILE cache entry is passed, specified crosstool file will be used When using this option to cross-compile, it is required to specify CMAKE_SYSTEM_NAME in the cache_entriesBooleanoptionalTrue
installIf True, the cmake --install comand will be performed after a buildBooleanoptionalTrue
install_argsArguments for the CMake install commandList of stringsoptional[]
lib_nameLibrary name. Defines the name of the install directory and the name of the static library, if no output files parameters are defined (any of static_libraries, shared_libraries, interface_libraries, binaries_names) Optional. If not defined, defaults to the target's name.Stringoptional""
lib_sourceLabel with source code to build. Typically a filegroup for the source of remote repository. Mandatory.Labelrequired
linkoptsOptional link options to be passed up to the dependencies of this libraryList of stringsoptional[]
out_bin_dirOptional name of the output subdirectory with the binary files, defaults to 'bin'.Stringoptional"bin"
out_binariesOptional names of the resulting binaries.List of stringsoptional[]
out_headers_onlyFlag variable to indicate that the library produces only headersBooleanoptionalFalse
out_include_dirOptional name of the output subdirectory with the header files, defaults to 'include'.Stringoptional"include"
out_interface_libsOptional names of the resulting interface libraries.List of stringsoptional[]
out_lib_dirOptional name of the output subdirectory with the library files, defaults to 'lib'.Stringoptional"lib"
out_shared_libsOptional names of the resulting shared libraries.List of stringsoptional[]
out_static_libsOptional names of the resulting static libraries. Note that if out_headers_only, out_static_libs, out_shared_libs, and out_binaries are not set, default lib_name.a/lib_name.lib static library is assumedList of stringsoptional[]
postfix_scriptOptional part of the shell script to be added after the make commandsStringoptional""
targetsA list of targets with in the foreign build system to produce. An empty string ("") will result in a call to the underlying build system with no explicit target setList of stringsoptional[]
tools_depsOptional tools to be copied into the directory structure. Similar to deps, those directly required for the external building of the library/binaries.List of labelsoptional[]
working_directoryWorking directory, with the main CMakeLists.txt (otherwise, the top directory of the lib_source label files is used.)Stringoptional""

cmake_tool

cmake_tool(name, srcs)

Rule for building CMake. Invokes bootstrap script and make install.

ATTRIBUTES

NameDescriptionTypeMandatoryDefault
nameA unique name for this target.Namerequired
srcsThe target containing the build tool's sourcesLabelrequired

configure_make

configure_make(name, additional_inputs, additional_tools, alwayslink, args, autoconf,
               autoconf_env_vars, autoconf_options, autogen, autogen_command, autogen_env_vars,
               autogen_options, autoreconf, autoreconf_env_vars, autoreconf_options,
               configure_command, configure_env_vars, configure_in_place, configure_options, data,
               defines, deps, env, install_prefix, lib_name, lib_source, linkopts, make_commands,
               out_bin_dir, out_binaries, out_headers_only, out_include_dir, out_interface_libs,
               out_lib_dir, out_shared_libs, out_static_libs, postfix_script, targets, tools_deps)

Rule for building external libraries with configure-make pattern. Some 'configure' script is invoked with --prefix=install (by default), and other parameters for compilation and linking, taken from Bazel C/C++ toolchain and passed dependencies. After configuration, GNU Make is called.

ATTRIBUTES

NameDescriptionTypeMandatoryDefault
nameA unique name for this target.Namerequired
additional_inputsOptional additional inputs to be declared as needed for the shell script action.Not used by the shell script part in cc_external_rule_impl.List of labelsoptional[]
additional_toolsOptional additional tools needed for the building. Not used by the shell script part in cc_external_rule_impl.List of labelsoptional[]
alwayslinkOptional. if true, link all the object files from the static library, even if they are not used.BooleanoptionalFalse
argsA list of arguments to pass to the call to makeList of stringsoptional[]
autoconfSet to True if 'autoconf' should be invoked before 'configure', currently requires configure_in_place to be True.BooleanoptionalFalse
autoconf_env_varsEnvironment variables to be set for 'autoconf' invocation.Dictionary: String -> Stringoptional{}
autoconf_optionsAny options to be put in the 'autoconf.sh' command line.List of stringsoptional[]
autogenSet to True if 'autogen.sh' should be invoked before 'configure', currently requires configure_in_place to be True.BooleanoptionalFalse
autogen_commandThe name of the autogen script file, default: autogen.sh. Many projects use autogen.sh however the Autotools FAQ recommends bootstrap so we provide this option to support that.Stringoptional"autogen.sh"
autogen_env_varsEnvironment variables to be set for 'autogen' invocation.Dictionary: String -> Stringoptional{}
autogen_optionsAny options to be put in the 'autogen.sh' command line.List of stringsoptional[]
autoreconfSet to True if 'autoreconf' should be invoked before 'configure.', currently requires configure_in_place to be True.BooleanoptionalFalse
autoreconf_env_varsEnvironment variables to be set for 'autoreconf' invocation.Dictionary: String -> Stringoptional{}
autoreconf_optionsAny options to be put in the 'autoreconf.sh' command line.List of stringsoptional[]
configure_commandThe name of the configuration script file, default: configure. The file must be in the root of the source directory.Stringoptional"configure"
configure_env_varsEnvironment variables to be set for the 'configure' invocation.Dictionary: String -> Stringoptional{}
configure_in_placeSet to True if 'configure' should be invoked in place, i.e. from its enclosing directory.BooleanoptionalFalse
configure_optionsAny options to be put on the 'configure' command line.List of stringsoptional[]
dataFiles needed by this rule at runtime. May list file or rule targets. Generally allows any target.List of labelsoptional[]
definesOptional compilation definitions to be passed to the dependencies of this library. They are NOT passed to the compiler, you should duplicate them in the configuration options.List of stringsoptional[]
depsOptional dependencies to be copied into the directory structure. Typically those directly required for the external building of the library/binaries. (i.e. those that the external buidl system will be looking for and paths to which are provided by the calling rule)List of labelsoptional[]
envEnvironment variables to set during the build. $(execpath) macros may be used to point at files which are listed as data deps, tools_deps, or additional_tools, but unlike with other rules, these will be replaced with absolute paths to those files, because the build does not run in the exec root. No other macros are supported.Dictionary: String -> Stringoptional{}
install_prefixInstall prefix, i.e. relative path to where to install the result of the build. Passed to the 'configure' script with --prefix flag.Stringoptional""
lib_nameLibrary name. Defines the name of the install directory and the name of the static library, if no output files parameters are defined (any of static_libraries, shared_libraries, interface_libraries, binaries_names) Optional. If not defined, defaults to the target's name.Stringoptional""
lib_sourceLabel with source code to build. Typically a filegroup for the source of remote repository. Mandatory.Labelrequired
linkoptsOptional link options to be passed up to the dependencies of this libraryList of stringsoptional[]
make_commandsOptional make commands.List of stringsoptional["make", "make install"]
out_bin_dirOptional name of the output subdirectory with the binary files, defaults to 'bin'.Stringoptional"bin"
out_binariesOptional names of the resulting binaries.List of stringsoptional[]
out_headers_onlyFlag variable to indicate that the library produces only headersBooleanoptionalFalse
out_include_dirOptional name of the output subdirectory with the header files, defaults to 'include'.Stringoptional"include"
out_interface_libsOptional names of the resulting interface libraries.List of stringsoptional[]
out_lib_dirOptional name of the output subdirectory with the library files, defaults to 'lib'.Stringoptional"lib"
out_shared_libsOptional names of the resulting shared libraries.List of stringsoptional[]
out_static_libsOptional names of the resulting static libraries. Note that if out_headers_only, out_static_libs, out_shared_libs, and out_binaries are not set, default lib_name.a/lib_name.lib static library is assumedList of stringsoptional[]
postfix_scriptOptional part of the shell script to be added after the make commandsStringoptional""
targetsA list of targets within the foreign build system to produce. An empty string ("") will result in a call to the underlying build system with no explicit target setList of stringsoptional["", "install"]
tools_depsOptional tools to be copied into the directory structure. Similar to deps, those directly required for the external building of the library/binaries.List of labelsoptional[]

make

make(name, additional_inputs, additional_tools, alwayslink, args, data, defines, deps, env,
     lib_name, lib_source, linkopts, out_bin_dir, out_binaries, out_headers_only, out_include_dir,
     out_interface_libs, out_lib_dir, out_shared_libs, out_static_libs, postfix_script, targets,
     tools_deps)

Rule for building external libraries with GNU Make. GNU Make commands (make and make install by default) are invoked with prefix="install" (by default), and other environment variables for compilation and linking, taken from Bazel C/C++ toolchain and passed dependencies.

ATTRIBUTES

NameDescriptionTypeMandatoryDefault
nameA unique name for this target.Namerequired
additional_inputsOptional additional inputs to be declared as needed for the shell script action.Not used by the shell script part in cc_external_rule_impl.List of labelsoptional[]
additional_toolsOptional additional tools needed for the building. Not used by the shell script part in cc_external_rule_impl.List of labelsoptional[]
alwayslinkOptional. if true, link all the object files from the static library, even if they are not used.BooleanoptionalFalse
argsA list of arguments to pass to the call to makeList of stringsoptional[]
dataFiles needed by this rule at runtime. May list file or rule targets. Generally allows any target.List of labelsoptional[]
definesOptional compilation definitions to be passed to the dependencies of this library. They are NOT passed to the compiler, you should duplicate them in the configuration options.List of stringsoptional[]
depsOptional dependencies to be copied into the directory structure. Typically those directly required for the external building of the library/binaries. (i.e. those that the external buidl system will be looking for and paths to which are provided by the calling rule)List of labelsoptional[]
envEnvironment variables to set during the build. $(execpath) macros may be used to point at files which are listed as data deps, tools_deps, or additional_tools, but unlike with other rules, these will be replaced with absolute paths to those files, because the build does not run in the exec root. No other macros are supported.Dictionary: String -> Stringoptional{}
lib_nameLibrary name. Defines the name of the install directory and the name of the static library, if no output files parameters are defined (any of static_libraries, shared_libraries, interface_libraries, binaries_names) Optional. If not defined, defaults to the target's name.Stringoptional""
lib_sourceLabel with source code to build. Typically a filegroup for the source of remote repository. Mandatory.Labelrequired
linkoptsOptional link options to be passed up to the dependencies of this libraryList of stringsoptional[]
out_bin_dirOptional name of the output subdirectory with the binary files, defaults to 'bin'.Stringoptional"bin"
out_binariesOptional names of the resulting binaries.List of stringsoptional[]
out_headers_onlyFlag variable to indicate that the library produces only headersBooleanoptionalFalse
out_include_dirOptional name of the output subdirectory with the header files, defaults to 'include'.Stringoptional"include"
out_interface_libsOptional names of the resulting interface libraries.List of stringsoptional[]
out_lib_dirOptional name of the output subdirectory with the library files, defaults to 'lib'.Stringoptional"lib"
out_shared_libsOptional names of the resulting shared libraries.List of stringsoptional[]
out_static_libsOptional names of the resulting static libraries. Note that if out_headers_only, out_static_libs, out_shared_libs, and out_binaries are not set, default lib_name.a/lib_name.lib static library is assumedList of stringsoptional[]
postfix_scriptOptional part of the shell script to be added after the make commandsStringoptional""
targetsA list of targets within the foreign build system to produce. An empty string ("") will result in a call to the underlying build system with no explicit target setList of stringsoptional["", "install"]
tools_depsOptional tools to be copied into the directory structure. Similar to deps, those directly required for the external building of the library/binaries.List of labelsoptional[]

make_tool

make_tool(name, srcs)

Rule for building Make. Invokes configure script and make install.

ATTRIBUTES

NameDescriptionTypeMandatoryDefault
nameA unique name for this target.Namerequired
srcsThe target containing the build tool's sourcesLabelrequired

native_tool_toolchain

native_tool_toolchain(name, path, target)

Rule for defining the toolchain data of the native tools (cmake, ninja), to be used by rules_foreign_cc with toolchain types @rules_foreign_cc//toolchains:cmake_toolchain and @rules_foreign_cc//toolchains:ninja_toolchain.

ATTRIBUTES

NameDescriptionTypeMandatoryDefault
nameA unique name for this target.Namerequired
pathAbsolute path to the tool in case the tool is preinstalled on the machine. Relative path to the tool in case the tool is built as part of a build; the path should be relative to the bazel-genfiles, i.e. it should start with the name of the top directory of the built tree artifact. (Please see the example //examples:built_cmake_toolchain)Stringoptional""
targetIf the tool is preinstalled, must be None. If the tool is built as part of the build, the corresponding build target, which should produce the tree artifact with the binary to call.LabeloptionalNone

ninja

ninja(name, additional_inputs, additional_tools, alwayslink, args, data, defines, deps, directory,
      env, lib_name, lib_source, linkopts, out_bin_dir, out_binaries, out_headers_only,
      out_include_dir, out_interface_libs, out_lib_dir, out_shared_libs, out_static_libs,
      postfix_script, targets, tools_deps)

Rule for building external libraries with Ninja.

ATTRIBUTES

NameDescriptionTypeMandatoryDefault
nameA unique name for this target.Namerequired
additional_inputsOptional additional inputs to be declared as needed for the shell script action.Not used by the shell script part in cc_external_rule_impl.List of labelsoptional[]
additional_toolsOptional additional tools needed for the building. Not used by the shell script part in cc_external_rule_impl.List of labelsoptional[]
alwayslinkOptional. if true, link all the object files from the static library, even if they are not used.BooleanoptionalFalse
argsA list of arguments to pass to the call to ninjaList of stringsoptional[]
dataFiles needed by this rule at runtime. May list file or rule targets. Generally allows any target.List of labelsoptional[]
definesOptional compilation definitions to be passed to the dependencies of this library. They are NOT passed to the compiler, you should duplicate them in the configuration options.List of stringsoptional[]
depsOptional dependencies to be copied into the directory structure. Typically those directly required for the external building of the library/binaries. (i.e. those that the external buidl system will be looking for and paths to which are provided by the calling rule)List of labelsoptional[]
directoryA directory to pass as the -C argument. The rule will always use the root directory of the lib_sources attribute if this attribute is not setStringoptional""
envEnvironment variables to set during the build. $(execpath) macros may be used to point at files which are listed as data deps, tools_deps, or additional_tools, but unlike with other rules, these will be replaced with absolute paths to those files, because the build does not run in the exec root. No other macros are supported.Dictionary: String -> Stringoptional{}
lib_nameLibrary name. Defines the name of the install directory and the name of the static library, if no output files parameters are defined (any of static_libraries, shared_libraries, interface_libraries, binaries_names) Optional. If not defined, defaults to the target's name.Stringoptional""
lib_sourceLabel with source code to build. Typically a filegroup for the source of remote repository. Mandatory.Labelrequired
linkoptsOptional link options to be passed up to the dependencies of this libraryList of stringsoptional[]
out_bin_dirOptional name of the output subdirectory with the binary files, defaults to 'bin'.Stringoptional"bin"
out_binariesOptional names of the resulting binaries.List of stringsoptional[]
out_headers_onlyFlag variable to indicate that the library produces only headersBooleanoptionalFalse
out_include_dirOptional name of the output subdirectory with the header files, defaults to 'include'.Stringoptional"include"
out_interface_libsOptional names of the resulting interface libraries.List of stringsoptional[]
out_lib_dirOptional name of the output subdirectory with the library files, defaults to 'lib'.Stringoptional"lib"
out_shared_libsOptional names of the resulting shared libraries.List of stringsoptional[]
out_static_libsOptional names of the resulting static libraries. Note that if out_headers_only, out_static_libs, out_shared_libs, and out_binaries are not set, default lib_name.a/lib_name.lib static library is assumedList of stringsoptional[]
postfix_scriptOptional part of the shell script to be added after the make commandsStringoptional""
targetsA list of targets with in the foreign build system to produce. An empty string ("") will result in a call to the underlying build system with no explicit target setList of stringsoptional[]
tools_depsOptional tools to be copied into the directory structure. Similar to deps, those directly required for the external building of the library/binaries.List of labelsoptional[]

ninja_tool

ninja_tool(name, srcs)

Rule for building Ninja. Invokes configure script.

ATTRIBUTES

NameDescriptionTypeMandatoryDefault
nameA unique name for this target.Namerequired
srcsThe target containing the build tool's sourcesLabelrequired

ForeignCcArtifactInfo

ForeignCcArtifactInfo(bin_dir_name, gen_dir, include_dir_name, lib_dir_name)

Groups information about the external library install directory, and relative bin, include and lib directories.

Serves to pass transitive information about externally built artifacts up the dependency chain.

Can not be used as a top-level provider. Instances of ForeignCcArtifactInfo are encapsulated in a depset ForeignCcDepsInfo#artifacts.

FIELDS

NameDescription
bin_dir_nameBin directory, relative to install directory
gen_dirInstall directory
include_dir_nameInclude directory, relative to install directory
lib_dir_nameLib directory, relative to install directory

ForeignCcDepsInfo

ForeignCcDepsInfo(artifacts)

Provider to pass transitive information about external libraries.

FIELDS

NameDescription
artifactsDepset of ForeignCcArtifactInfo

ToolInfo

ToolInfo(path, target)

Information about the native tool

FIELDS

NameDescription
pathAbsolute path to the tool in case the tool is preinstalled on the machine. Relative path to the tool in case the tool is built as part of a build; the path should be relative to the bazel-genfiles, i.e. it should start with the name of the top directory of the built tree artifact. (Please see the example //examples:built_cmake_toolchain)
targetIf the tool is preinstalled, must be None. If the tool is built as part of the build, the corresponding build target, which should produce the tree artifact with the binary to call.

rules_foreign_cc_dependencies

rules_foreign_cc_dependencies(native_tools_toolchains, register_default_tools, cmake_version,
                              make_version, ninja_version, register_preinstalled_tools,
                              register_built_tools)

Call this function from the WORKSPACE file to initialize rules_foreign_cc dependencies and let neccesary code generation happen (Code generation is needed to support different variants of the C++ Starlark API.).

PARAMETERS

NameDescriptionDefault Value
native_tools_toolchainspass the toolchains for toolchain types '@rules_foreign_cc//toolchains:cmake_toolchain' and '@rules_foreign_cc//toolchains:ninja_toolchain' with the needed platform constraints. If you do not pass anything, registered default toolchains will be selected (see below).[]
register_default_toolsIf True, the cmake and ninja toolchains, calling corresponding preinstalled binaries by name (cmake, ninja) will be registered after 'native_tools_toolchains' without any platform constraints. The default is True.True
cmake_versionThe target version of the cmake toolchain if register_default_tools or register_built_tools is set to True."3.20.2"
make_versionThe target version of the default make toolchain if register_built_tools is set to True."4.3"
ninja_versionThe target version of the ninja toolchain if register_default_tools or register_built_tools is set to True."1.10.2"
register_preinstalled_toolsIf true, toolchains will be registered for the native built tools installed on the exec hostTrue
register_built_toolsIf true, toolchains that build the tools from source are registeredTrue