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Utility functions that replace old C++ Starlark API using the new API.
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| # Copyright 2019 The Bazel Authors. All rights reserved. | |
| # | |
| # Licensed under the Apache License, Version 2.0 (the "License"); | |
| # you may not use this file except in compliance with the License. | |
| # You may obtain a copy of the License at | |
| # | |
| # http://www.apache.org/licenses/LICENSE-2.0 | |
| # | |
| # Unless required by applicable law or agreed to in writing, software | |
| # distributed under the License is distributed on an "AS IS" BASIS, | |
| # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. | |
| # See the License for the specific language governing permissions and | |
| # limitations under the License. | |
| """ | |
| Utility functions that replace old C++ Starlark API using the new API. | |
| See migration instructions in https://github.com/bazelbuild/bazel/issues/7036 | |
| Replacements: | |
| dep.cc.transitive_headers -> dep[CcInfo].compilation_context.headers | |
| dep.cc.defines -> dep[CcInfo].compilation_context.defines.to_list() | |
| dep.cc.system_include_directories -> dep[CcInfo].compilation_context.system_includes.to_list() | |
| dep.cc.include_directories -> dep[CcInfo].compilation_context.includes.to_list() | |
| dep.cc.quote_include_directories -> dep[CcInfo].compilation_context.quote_includes.to_list() | |
| dep.cc.link_flags = dep[CcInfo].linking_context.user_link_flags | |
| dep.cc.libs = get_libs_for_static_executable(dep) | |
| dep.cc.compile_flags = get_compile_flags(dep) | |
| """ | |
| def get_libs_for_static_executable(dep): | |
| """ | |
| Finds the libraries used for linking an executable statically. | |
| This replaces the old API dep.cc.libs | |
| Args: | |
| dep: Target | |
| Returns: | |
| A list of File instances, these are the libraries used for linking. | |
| """ | |
| libraries_to_link = dep[CcInfo].linking_context.libraries_to_link | |
| libs = [] | |
| for library_to_link in libraries_to_link: | |
| if library_to_link.static_library != None: | |
| libs.append(library_to_link.static_library) | |
| elif library_to_link.pic_static_library != None: | |
| libs.append(library_to_link.pic_static_library) | |
| elif library_to_link.interface_library != None: | |
| libs.append(library_to_link.interface_library) | |
| elif library_to_link.dynamic_library != None: | |
| libs.append(library_to_link.dynamic_library) | |
| return depset(libs) | |
| def get_compile_flags(dep): | |
| """ | |
| Builds compilation flags. This replaces the old API dep.cc.compile_flags | |
| This is not the command line that C++ rules will use. For that the toolchain API should be | |
| used (feature configuration and variables). | |
| Args: | |
| dep: Target | |
| Returns: | |
| A list of strings | |
| """ | |
| options = [] | |
| compilation_context = dep[CcInfo].compilation_context | |
| for define in compilation_context.defines.to_list(): | |
| options.append("-D{}".format(define)) | |
| for system_include in compilation_context.system_includes.to_list(): | |
| if len(system_include) == 0: | |
| system_include = "." | |
| options.append("-isystem {}".format(system_include)) | |
| for include in compilation_context.includes.to_list(): | |
| if len(include) == 0: | |
| include = "." | |
| options.append("-I {}".format(include)) | |
| for quote_include in compilation_context.quote_includes.to_list(): | |
| if len(quote_include) == 0: | |
| quote_include = "." | |
| options.append("-iquote {}".format(quote_include)) | |
| return options |
Author
Sure. I specified the same license as other Bazel files.
Is there a recommend way to handle the alwayslink attribute?
Granted, it looks like this function would be deprecated with --incompatible_require_linker_input_cc_api per bazelbuild/bazel#10860
Author
Hi David,
This gist is for an old C++ Starlark provider that is no longer supported. I added the code here as guidance but it's not maintained. As you mention, once --incompatible_require_linker_input_cc_api is flipped, it will stop working.
Regarding the "alwayslink" attribute, as far as I can tell, it is not mentioned here because the old API didn't have it, therefore, there was no need to mention it in the shim.
Hi! Nice work @oquenchil 👍
Just one note: in get_compile_flags you are missing local_defines
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I would like to use the content of this gist. However, as there is no license specified, all rights are retained and I am unable to do so. Could you kindly specify a license for this gist?