cc_common

Utilities for C++ compilation, linking, and command line generation.

Members

action_is_enabled
CcToolchainInfo
compile
configure_features
create_cc_toolchain_config_info
create_compilation_context
create_compilation_outputs
create_compile_variables
create_library_to_link
create_link_variables
create_linker_input
create_linking_context
create_linking_context_from_compilation_outputs
do_not_use_tools_cpp_compiler_present
get_environment_variables
get_execution_requirements
get_memory_inefficient_command_line
get_tool_for_action
is_enabled
link
merge_cc_infos
merge_compilation_outputs

action_is_enabled

bool cc_common.action_is_enabled(feature_configuration, action_name)

Returns True if given action_config is enabled in the feature configuration.

Parameters

Parameter Description

Parameter	Description
`feature_configuration`	`FeatureConfiguration` Feature configuration to be queried.
`action_name`	Name of the action_config.

feature_configuration

FeatureConfiguration

Feature configuration to be queried.

action_name

Name of the action_config.

CcToolchainInfo

Provider cc_common.CcToolchainInfo

The key used to retrieve the provider that contains information about the C++ toolchain being used

compile

tuple cc_common.compile(actions, feature_configuration, cc_toolchain, srcs=[], public_hdrs=[], private_hdrs=[], includes=[], quote_includes=[], system_includes=[], framework_includes=[], defines=[], local_defines=[], include_prefix='', strip_include_prefix='', user_compile_flags=[], compilation_contexts=[], name, disallow_pic_outputs=False, disallow_nopic_outputs=False, additional_inputs=[])

Should be used for C++ compilation. Returns tuple of (CompilationContext, CcCompilationOutputs).

Parameters

Parameter	Description
`actions`	`actions` `actions` object.
`feature_configuration`	`FeatureConfiguration` `feature_configuration` to be queried.
`cc_toolchain`	`CcToolchainInfo` `CcToolchainInfo` provider to be used.
`srcs`	`sequence` The list of source files to be compiled.
`public_hdrs`	`sequence` List of headers needed for compilation of srcs and may be included by dependent rules transitively.
`private_hdrs`	`sequence` List of headers needed for compilation of srcs and NOT to be included by dependent rules.
`includes`	`sequence` Search paths for header files referenced both by angle bracket and quotes. Usually passed with -I. Propagated to dependents transitively.
`quote_includes`	`sequence` Search paths for header files referenced by quotes, e.g. #include "foo/bar/header.h". They can be either relative to the exec root or absolute. Usually passed with -iquote. Propagated to dependents transitively.
`system_includes`	`sequence` Search paths for header files referenced by angle brackets, e.g. #include <foo/bar/header.h>. They can be either relative to the exec root or absolute. Usually passed with -isystem. Propagated to dependents transitively.
`framework_includes`	`sequence` Search paths for header files from Apple frameworks. They can be either relative to the exec root or absolute. Usually passed with -F. Propagated to dependents transitively.
`defines`	`sequence` Set of defines needed to compile this target. Each define is a string. Propagated to dependents transitively.
`local_defines`	`sequence` Set of defines needed to compile this target. Each define is a string. Not propagated to dependents transitively.
`include_prefix`	`string` The prefix to add to the paths of the headers of this rule. When set, the headers in the hdrs attribute of this rule are accessible at is the value of this attribute prepended to their repository-relative path. The prefix in the strip_include_prefix attribute is removed before this prefix is added.
`strip_include_prefix`	`string` The prefix to strip from the paths of the headers of this rule. When set, the headers in the hdrs attribute of this rule are accessible at their path with this prefix cut off. If it's a relative path, it's taken as a package-relative one. If it's an absolute one, it's understood as a repository-relative path. The prefix in the include_prefix attribute is added after this prefix is stripped.
`user_compile_flags`	`sequence` Additional list of compilation options.
`compilation_contexts`	`sequence` Headers from dependencies used for compilation.
`name`	`string` This is used for naming the output artifacts of actions created by this method.
`disallow_pic_outputs`	`bool` Whether PIC outputs should be created.
`disallow_nopic_outputs`	`bool` Whether NOPIC outputs should be created.
`additional_inputs`	`sequence` List of additional files needed for compilation of srcs

configure_features

FeatureConfiguration cc_common.configure_features(ctx=None, cc_toolchain, requested_features=[], unsupported_features=[])

Creates a feature_configuration instance. Requires the cpp configuration fragment.

Parameters

Parameter	Description
`ctx`	`ctx` The rule context.
`cc_toolchain`	`CcToolchainInfo` cc_toolchain for which we configure features.
`requested_features`	`sequence` List of features to be enabled.
`unsupported_features`	`sequence` List of features that are unsupported by the current rule.

create_cc_toolchain_config_info

CcToolchainConfigInfo cc_common.create_cc_toolchain_config_info(ctx, features=[], action_configs=[], artifact_name_patterns=[], cxx_builtin_include_directories=[], toolchain_identifier, host_system_name, target_system_name, target_cpu, target_libc, compiler, abi_version, abi_libc_version, tool_paths=[], make_variables=[], builtin_sysroot=None, cc_target_os=None)

Creates a CcToolchainConfigInfo provider

Parameters

Parameter	Description
`ctx`	`ctx` The rule context.
`features`	`sequence` A list of features.
`action_configs`	`sequence` A list of action_configs.
`artifact_name_patterns`	`sequence` A list of artifact_name_patterns.
`cxx_builtin_include_directories`	`sequence` Built-in include directories for C++ compilation. These should be the exact paths used by the compiler, and are generally relative to the exec root. The paths used by the compiler can be determined by 'gcc -E -xc++ - -v'. We currently use the C++ paths also for C compilation, which is safe as long as there are no name clashes between C++ and C header files. Relative paths are resolved relative to the configuration file directory. If the compiler has --sysroot support, then these paths should use %sysroot% rather than the include path, and specify the sysroot attribute in order to give bazel the information necessary to make the correct replacements.
`toolchain_identifier`	`string` The unique identifier of the toolchain within the crosstool release. It must be possible to use this as a directory name in a path. It has to match the following regex: [a-zA-Z_][\.\- \w]*
`host_system_name`	`string` The system name which is required by the toolchain to run.
`target_system_name`	`string` The GNU System Name.
`target_cpu`	`string` The target architecture string.
`target_libc`	`string` The libc version string (e.g. "glibc-2.2.2").
`compiler`	`string` The compiler version string (e.g. "gcc-4.1.1").
`abi_version`	`string` The abi in use, which is a gcc version. E.g.: "gcc-3.4"
`abi_libc_version`	`string` The glibc version used by the abi we're using.
`tool_paths`	`sequence` A list of tool_paths.
`make_variables`	`sequence` A list of make_variables.
`builtin_sysroot`	`string; or None` The built-in sysroot. If this attribute is not present, Bazel does not allow using a different sysroot, i.e. through the --grte_top option.
`cc_target_os`	`string; or None` Internal purpose only, do not use.

create_compilation_context

CompilationContext cc_common.create_compilation_context(headers=unbound, system_includes=unbound, includes=unbound, quote_includes=unbound, framework_includes=unbound, defines=unbound, local_defines=unbound)

Creates a CompilationContext.

Parameters

Parameter	Description
`headers`	Set of headers needed to compile this target
`system_includes`	Set of search paths for header files referenced by angle brackets, i.e. #include <foo/bar/header.h>. They can be either relative to the exec root or absolute. Usually passed with -isystem
`includes`	Set of search paths for header files referenced both by angle bracket and quotes.Usually passed with -I
`quote_includes`	Set of search paths for header files referenced by quotes, i.e. #include "foo/bar/header.h". They can be either relative to the exec root or absolute. Usually passed with -iquote
`framework_includes`	Set of framework search paths for header files (Apple platform only)
`defines`	Set of defines needed to compile this target. Each define is a string. Propagated transitively to dependents.
`local_defines`	Set of defines needed to compile this target. Each define is a string. Not propagated transitively to dependents.

create_compilation_outputs

CcCompilationOutputs cc_common.create_compilation_outputs(objects=None, pic_objects=None)

Create compilation outputs object.

Parameters

Parameter Description

Parameter	Description
`objects`	`depset; or None` List of object files.
`pic_objects`	`depset; or None` List of pic object files.

objects

depset; or None

List of object files.

pic_objects

depset; or None

List of pic object files.

create_compile_variables

Variables cc_common.create_compile_variables(cc_toolchain, feature_configuration, source_file=None, output_file=None, user_compile_flags=None, include_directories=None, quote_include_directories=None, system_include_directories=None, framework_include_directories=None, preprocessor_defines=None, thinlto_index=None, thinlto_input_bitcode_file=None, thinlto_output_object_file=None, use_pic=False, add_legacy_cxx_options=False)

Returns variables used for compilation actions.

Parameters

Parameter	Description
`cc_toolchain`	`CcToolchainInfo` cc_toolchain for which we are creating build variables.
`feature_configuration`	`FeatureConfiguration` Feature configuration to be queried.
`source_file`	Optional source file for the compilation. Please prefer passing source_file here over appending it to the end of the command line generated from cc_common.get_memory_inefficient_command_line, as then it's in the power of the toolchain author to properly specify and position compiler flags.
`output_file`	Optional output file of the compilation. Please prefer passing output_file here over appending it to the end of the command line generated from cc_common.get_memory_inefficient_command_line, as then it's in the power of the toolchain author to properly specify and position compiler flags.
`user_compile_flags`	`None; or sequence` List of additional compilation flags (copts).
`include_directories`	`None; or depset` Depset of include directories.
`quote_include_directories`	`None; or depset` Depset of quote include directories.
`system_include_directories`	`None; or depset` Depset of system include directories.
`framework_include_directories`	`None; or depset` Depset of framework include directories.
`preprocessor_defines`	`None; or depset` Depset of preprocessor defines.
`thinlto_index`	`None; or string` LTO index file path.
`thinlto_input_bitcode_file`	`None; or string` Bitcode file that is input to LTO backend.
`thinlto_output_object_file`	`None; or string` Object file that is output by LTO backend.
`use_pic`	When true the compilation will generate position independent code.
`add_legacy_cxx_options`	Unused.

create_library_to_link

LibraryToLink cc_common.create_library_to_link(actions, feature_configuration, cc_toolchain, static_library=None, pic_static_library=None, dynamic_library=None, interface_library=None, pic_objects=unbound, objects=unbound, alwayslink=False, dynamic_library_symlink_path='', interface_library_symlink_path='')

Creates LibraryToLink

Parameters

Parameter	Description
`actions`	`actions` `actions` object.
`feature_configuration`	`FeatureConfiguration` `feature_configuration` to be queried.
`cc_toolchain`	`CcToolchainInfo` `CcToolchainInfo` provider to be used.
`static_library`	`File` `File` of static library to be linked.
`pic_static_library`	`File` `File` of pic static library to be linked.
`dynamic_library`	`File` `File` of dynamic library to be linked. Always used for runtime and used for linking if `interface_library` is not passed.
`interface_library`	`File` `File` of interface library to be linked.
`pic_objects`	`sequence of Files` Experimental, do not use
`objects`	`sequence of Files` Experimental, do not use
`alwayslink`	Whether to link the static library/objects in the --whole_archive block.
`dynamic_library_symlink_path`	`string` Override the default path of the dynamic library link in the solib directory. Empty string to use the default.
`interface_library_symlink_path`	`string` Override the default path of the interface library link in the solib directory. Empty string to use the default.

create_link_variables

Variables cc_common.create_link_variables(cc_toolchain, feature_configuration, library_search_directories=None, runtime_library_search_directories=None, user_link_flags=None, output_file=None, param_file=None, def_file=None, is_using_linker=True, is_linking_dynamic_library=False, must_keep_debug=True, use_test_only_flags=False, is_static_linking_mode=True)

Returns link variables used for linking actions.

Parameters

Parameter	Description
`cc_toolchain`	`CcToolchainInfo` cc_toolchain for which we are creating build variables.
`feature_configuration`	`FeatureConfiguration` Feature configuration to be queried.
`library_search_directories`	`None; or depset` Depset of directories where linker will look for libraries at link time.
`runtime_library_search_directories`	`None; or depset` Depset of directories where loader will look for libraries at runtime.
`user_link_flags`	`None; or sequence` List of additional link flags (linkopts).
`output_file`	Optional output file path.
`param_file`	Optional param file path.
`def_file`	Optional .def file path.
`is_using_linker`	True when using linker, False when archiver. Caller is responsible for keeping this in sync with action name used (is_using_linker = True for linking executable or dynamic library, is_using_linker = False for archiving static library).
`is_linking_dynamic_library`	True when creating dynamic library, False when executable or static library. Caller is responsible for keeping this in sync with action name used. This field will be removed once b/65151735 is fixed.
`must_keep_debug`	When set to True, bazel will expose 'strip_debug_symbols' variable, which is usually used to use the linker to strip debug symbols from the output file.
`use_test_only_flags`	When set to true, 'is_cc_test' variable will be set.
`is_static_linking_mode`	Unused.

create_linker_input

LinkerInput cc_common.create_linker_input(owner, libraries=None, user_link_flags=None, additional_inputs=None)

Creates a LinkingContext.

Parameters

Parameter	Description
`owner`	`Label` The label of the target that produced all files used in this input.
`libraries`	`None; or depset` List of `LibraryToLink`.
`user_link_flags`	`None; or depset` List of user link flags passed as strings.
`additional_inputs`	`None; or depset` For additional inputs to the linking action, e.g.: linking scripts.

create_linking_context

LinkingContext cc_common.create_linking_context(linker_inputs=None, libraries_to_link=None, user_link_flags=None, additional_inputs=None)

Creates a LinkingContext.

Parameters

Parameter	Description
`linker_inputs`	`None; or depset` Depset of `LinkerInput`.
`libraries_to_link`	`None; or sequence` Deprecated. This parameter is deprecated and will be removed soon. Please do not depend on it. It is disabled with `---incompatible_require_linker_input_cc_api`. Use this flag to verify your code is compatible with its imminent removal. List of `LibraryToLink`.
`user_link_flags`	`None; or sequence` Deprecated. This parameter is deprecated and will be removed soon. Please do not depend on it. It is disabled with `---incompatible_require_linker_input_cc_api`. Use this flag to verify your code is compatible with its imminent removal. List of user link flags passed as strings.
`additional_inputs`	`None; or sequence` Deprecated. This parameter is deprecated and will be removed soon. Please do not depend on it. It is disabled with `---incompatible_require_linker_input_cc_api`. Use this flag to verify your code is compatible with its imminent removal. For additional inputs to the linking action, e.g.: linking scripts.

create_linking_context_from_compilation_outputs

tuple cc_common.create_linking_context_from_compilation_outputs(actions, feature_configuration, cc_toolchain, compilation_outputs, user_link_flags=[], linking_contexts=[], name, language='c++', alwayslink=False, additional_inputs=[], disallow_static_libraries=False, disallow_dynamic_library=False, grep_includes=None)

Should be used for creating library rules that can propagate information downstream in order to be linked later by a top level rule that does transitive linking to create an executable or dynamic library. Returns tuple of (CcLinkingContext, CcLinkingOutputs).

Parameters

Parameter	Description
`actions`	`actions` `actions` object.
`feature_configuration`	`FeatureConfiguration` `feature_configuration` to be queried.
`cc_toolchain`	`CcToolchainInfo` `CcToolchainInfo` provider to be used.
`compilation_outputs`	`CcCompilationOutputs` Compilation outputs containing object files to link.
`user_link_flags`	`sequence` Additional list of linking options.
`linking_contexts`	`sequence` Libraries from dependencies. These libraries will be linked into the output artifact of the link() call, be it a binary or a library.
`name`	`string` This is used for naming the output artifacts of actions created by this method.
`language`	`string` Only C++ supported for now. Do not use this parameter.
`alwayslink`	`bool` Whether this library should always be linked.
`additional_inputs`	`sequence` For additional inputs to the linking action, e.g.: linking scripts.
`disallow_static_libraries`	`bool` Whether static libraries should be created.
`disallow_dynamic_library`	`bool` Whether a dynamic library should be created.
`grep_includes`	`File; or None`

do_not_use_tools_cpp_compiler_present

None cc_common.do_not_use_tools_cpp_compiler_present

Do not use this field, its only puprose is to help with migration from config_setting.values{'compiler') to config_settings.flag_values{'@bazel_tools//tools/cpp:compiler'}

get_environment_variables

dict cc_common.get_environment_variables(feature_configuration, action_name, variables)

Returns environment variables to be set for given action.

Parameters

Parameter Description

Parameter	Description
`feature_configuration`	`FeatureConfiguration` Feature configuration to be queried.
`action_name`	Name of the action. Has to be one of the names in @bazel_tools//tools/build_defs/cc:action_names.bzl (https://github.com/bazelbuild/bazel/blob/master/tools/build_defs/cc/action_names.bzl)
`variables`	`Variables` Build variables to be used for template expansion.

feature_configuration

FeatureConfiguration

Feature configuration to be queried.

action_name

Name of the action. Has to be one of the names in @bazel_tools//tools/build_defs/cc:action_names.bzl (https://github.com/bazelbuild/bazel/blob/master/tools/build_defs/cc/action_names.bzl)

variables

Variables

Build variables to be used for template expansion.

get_execution_requirements

sequence cc_common.get_execution_requirements(feature_configuration, action_name)

Returns execution requirements for given action.

Parameters

Parameter Description

Parameter	Description
`feature_configuration`	`FeatureConfiguration` Feature configuration to be queried.
`action_name`	Name of the action. Has to be one of the names in @bazel_tools//tools/build_defs/cc:action_names.bzl (https://github.com/bazelbuild/bazel/blob/master/tools/build_defs/cc/action_names.bzl)

feature_configuration

FeatureConfiguration

Feature configuration to be queried.

action_name

Name of the action. Has to be one of the names in @bazel_tools//tools/build_defs/cc:action_names.bzl (https://github.com/bazelbuild/bazel/blob/master/tools/build_defs/cc/action_names.bzl)

get_memory_inefficient_command_line

sequence cc_common.get_memory_inefficient_command_line(feature_configuration, action_name, variables)

Returns flattened command line flags for given action, using given variables for expansion. Flattens nested sets and ideally should not be used, or at least should not outlive analysis. Work on memory efficient function returning Args is ongoing.

Parameters

Parameter Description

Parameter	Description
`feature_configuration`	`FeatureConfiguration` Feature configuration to be queried.
`action_name`	Name of the action. Has to be one of the names in @bazel_tools//tools/build_defs/cc:action_names.bzl (https://github.com/bazelbuild/bazel/blob/master/tools/build_defs/cc/action_names.bzl)
`variables`	`Variables` Build variables to be used for template expansions.

feature_configuration

FeatureConfiguration

Feature configuration to be queried.

action_name

Name of the action. Has to be one of the names in @bazel_tools//tools/build_defs/cc:action_names.bzl (https://github.com/bazelbuild/bazel/blob/master/tools/build_defs/cc/action_names.bzl)

variables

Variables

Build variables to be used for template expansions.

get_tool_for_action

string cc_common.get_tool_for_action(feature_configuration, action_name)

Returns tool path for given action.

Parameters

Parameter Description

Parameter	Description
`feature_configuration`	`FeatureConfiguration` Feature configuration to be queried.
`action_name`	Name of the action. Has to be one of the names in @bazel_tools//tools/build_defs/cc:action_names.bzl (https://github.com/bazelbuild/bazel/blob/master/tools/build_defs/cc/action_names.bzl)

feature_configuration

FeatureConfiguration

Feature configuration to be queried.

action_name

Name of the action. Has to be one of the names in @bazel_tools//tools/build_defs/cc:action_names.bzl (https://github.com/bazelbuild/bazel/blob/master/tools/build_defs/cc/action_names.bzl)

is_enabled

bool cc_common.is_enabled(feature_configuration, feature_name)

Returns True if given feature is enabled in the feature configuration.

Parameters

Parameter Description

Parameter	Description
`feature_configuration`	`FeatureConfiguration` Feature configuration to be queried.
`feature_name`	Name of the feature.

feature_configuration

FeatureConfiguration

Feature configuration to be queried.

feature_name

Name of the feature.

link

CcLinkingOutputs cc_common.link(actions, feature_configuration, cc_toolchain, compilation_outputs=None, user_link_flags=[], linking_contexts=[], name, language='c++', output_type='executable', link_deps_statically=True, stamp=0, additional_inputs=[], grep_includes=None)

Should be used for C++ transitive linking.

Parameters

Parameter	Description
`actions`	`actions` `actions` object.
`feature_configuration`	`FeatureConfiguration` `feature_configuration` to be queried.
`cc_toolchain`	`CcToolchainInfo` `CcToolchainInfo` provider to be used.
`compilation_outputs`	`CcCompilationOutputs; or None` Compilation outputs containing object files to link.
`user_link_flags`	`sequence` Additional list of linker options.
`linking_contexts`	`sequence` Linking contexts from dependencies to be linked into the linking context generated by this rule.
`name`	`string` This is used for naming the output artifacts of actions created by this method.
`language`	`string` Only C++ supported for now. Do not use this parameter.
`output_type`	`string` Can be either 'executable' or 'dynamic_library'.
`link_deps_statically`	`bool` True to link dependencies statically, False dynamically.
`stamp`	`int` Whether to include build information in the linked executable, if output_type is 'executable'. If 1, build information is always included. If 0 (the default build information is always excluded. If -1, uses the default behavior, which may be overridden by the --[no]stamp flag. This should be unset (or set to 0) when generating the executable output for test rules.
`additional_inputs`	`sequence` For additional inputs to the linking action, e.g.: linking scripts.
`grep_includes`	`File; or None`

merge_cc_infos

CcInfo cc_common.merge_cc_infos(direct_cc_infos=[], cc_infos=[])

Merges multiple CcInfos into one.

Parameters

Parameter Description

Parameter	Description
`direct_cc_infos`	`sequence` List of `CcInfo`s to be merged, whose headers will be exported by the direct fields in the returned provider.
`cc_infos`	`sequence` List of `CcInfo`s to be merged, whose headers will not be exported by the direct fields in the returned provider.

direct_cc_infos

sequence

List of CcInfos to be merged, whose headers will be exported by the direct fields in the returned provider.

cc_infos

sequence

List of CcInfos to be merged, whose headers will not be exported by the direct fields in the returned provider.

merge_compilation_outputs

CcCompilationOutputs cc_common.merge_compilation_outputs(compilation_outputs=[])

Merge compilation outputs.

Parameters

Parameter Description

Parameter	Description
`compilation_outputs`	`sequence`

compilation_outputs

sequence