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CcBinary.java
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CcBinary.java
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// Copyright 2014 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.
package com.google.devtools.build.lib.rules.cpp;
import static com.google.common.collect.ImmutableList.toImmutableList;
import static com.google.devtools.build.lib.rules.cpp.CppRuleClasses.DYNAMIC_LINKING_MODE;
import static com.google.devtools.build.lib.rules.cpp.CppRuleClasses.IS_CC_TEST_FEATURE_NAME;
import static com.google.devtools.build.lib.rules.cpp.CppRuleClasses.LEGACY_IS_CC_TEST_FEATURE_NAME;
import static com.google.devtools.build.lib.rules.cpp.CppRuleClasses.STATIC_LINKING_MODE;
import com.google.auto.value.AutoValue;
import com.google.common.annotations.VisibleForTesting;
import com.google.common.base.Function;
import com.google.common.base.Joiner;
import com.google.common.collect.ImmutableCollection;
import com.google.common.collect.ImmutableList;
import com.google.common.collect.ImmutableMap;
import com.google.common.collect.ImmutableSet;
import com.google.common.collect.Iterables;
import com.google.devtools.build.docgen.annot.DocCategory;
import com.google.devtools.build.lib.actions.Artifact;
import com.google.devtools.build.lib.actions.ExecutionRequirements;
import com.google.devtools.build.lib.actions.MutableActionGraph.ActionConflictException;
import com.google.devtools.build.lib.actions.ParamFileInfo;
import com.google.devtools.build.lib.actions.ParameterFile.ParameterFileType;
import com.google.devtools.build.lib.analysis.AnalysisUtils;
import com.google.devtools.build.lib.analysis.ConfiguredTarget;
import com.google.devtools.build.lib.analysis.FileProvider;
import com.google.devtools.build.lib.analysis.FilesToRunProvider;
import com.google.devtools.build.lib.analysis.MakeVariableSupplier.MapBackedMakeVariableSupplier;
import com.google.devtools.build.lib.analysis.OutputGroupInfo;
import com.google.devtools.build.lib.analysis.RuleConfiguredTargetBuilder;
import com.google.devtools.build.lib.analysis.RuleConfiguredTargetFactory;
import com.google.devtools.build.lib.analysis.RuleContext;
import com.google.devtools.build.lib.analysis.Runfiles;
import com.google.devtools.build.lib.analysis.RunfilesProvider;
import com.google.devtools.build.lib.analysis.RunfilesSupport;
import com.google.devtools.build.lib.analysis.TransitiveInfoCollection;
import com.google.devtools.build.lib.analysis.actions.Compression;
import com.google.devtools.build.lib.analysis.actions.CustomCommandLine;
import com.google.devtools.build.lib.analysis.actions.FileWriteAction;
import com.google.devtools.build.lib.analysis.actions.SpawnAction;
import com.google.devtools.build.lib.analysis.actions.SymlinkAction;
import com.google.devtools.build.lib.analysis.test.AnalysisFailure;
import com.google.devtools.build.lib.analysis.test.AnalysisFailureInfo;
import com.google.devtools.build.lib.analysis.test.ExecutionInfo;
import com.google.devtools.build.lib.analysis.test.InstrumentedFilesInfo;
import com.google.devtools.build.lib.collect.nestedset.Depset;
import com.google.devtools.build.lib.collect.nestedset.NestedSet;
import com.google.devtools.build.lib.collect.nestedset.NestedSetBuilder;
import com.google.devtools.build.lib.collect.nestedset.Order;
import com.google.devtools.build.lib.packages.BuiltinProvider;
import com.google.devtools.build.lib.packages.NativeInfo;
import com.google.devtools.build.lib.packages.Rule;
import com.google.devtools.build.lib.packages.StructImpl;
import com.google.devtools.build.lib.packages.TargetUtils;
import com.google.devtools.build.lib.packages.Type;
import com.google.devtools.build.lib.packages.semantics.BuildLanguageOptions;
import com.google.devtools.build.lib.rules.apple.ApplePlatform;
import com.google.devtools.build.lib.rules.cpp.CcCommon.CcFlagsSupplier;
import com.google.devtools.build.lib.rules.cpp.CcCommon.Language;
import com.google.devtools.build.lib.rules.cpp.CcCompilationHelper.CompilationInfo;
import com.google.devtools.build.lib.rules.cpp.CcLinkingContext.LinkOptions;
import com.google.devtools.build.lib.rules.cpp.CcToolchainFeatures.FeatureConfiguration;
import com.google.devtools.build.lib.rules.cpp.CppConfiguration.DynamicMode;
import com.google.devtools.build.lib.rules.cpp.CppConfiguration.Tool;
import com.google.devtools.build.lib.rules.cpp.Link.LinkTargetType;
import com.google.devtools.build.lib.rules.cpp.Link.LinkingMode;
import com.google.devtools.build.lib.util.Pair;
import com.google.devtools.build.lib.vfs.FileSystemUtils;
import com.google.devtools.build.lib.vfs.PathFragment;
import java.util.ArrayDeque;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.HashSet;
import java.util.List;
import java.util.Map;
import java.util.Queue;
import java.util.Set;
import javax.annotation.Nullable;
import net.starlark.java.annot.StarlarkBuiltin;
import net.starlark.java.annot.StarlarkMethod;
import net.starlark.java.eval.EvalException;
import net.starlark.java.eval.Sequence;
import net.starlark.java.eval.Starlark;
import net.starlark.java.eval.StarlarkThread;
import net.starlark.java.eval.Tuple;
/**
* A ConfiguredTarget for <code>cc_binary</code> rules.
*/
public abstract class CcBinary implements RuleConfiguredTargetFactory {
private final CppSemantics semantics;
protected CcBinary(CppSemantics semantics) {
this.semantics = semantics;
}
/**
* The maximum number of inputs for any single .dwp generating action. For cases where
* this value is exceeded, the action is split up into "batches" that fall under the limit.
* See {@link #createDebugPackagerActions} for details.
*/
@VisibleForTesting
public static final int MAX_INPUTS_PER_DWP_ACTION = 100;
/**
* Intermediate dwps are written to this subdirectory under the main dwp's output path.
*/
@VisibleForTesting
public static final String INTERMEDIATE_DWP_DIR = "_dwps";
/**
* A string constant for the dynamic_link_test_srcs feature.
*
* <p>Enabling this feature forces srcs of test executables to be linked dynamically in
* DYNAMIC_MODE=AUTO.
*/
public static final String DYNAMIC_LINK_TEST_SRCS = "dynamic_link_test_srcs";
/**
* Provider that signals that rules that use launchers can use this target as the launcher.
*
* @deprecated This is google internal provider and it will be replaced with a more generally
* useful provider in Bazel. Do not use to implement support for launchers in new rules. It's
* only supported to be used in existing rules (PyBinary, JavaBinary, JavaTest).
*/
@Deprecated()
@StarlarkBuiltin(
name = "CcLauncherInfo",
documented = false,
doc =
"Provider that signals that rules that use launchers can use this target as "
+ "the launcher.",
category = DocCategory.TOP_LEVEL_TYPE)
public static class CcLauncherInfo extends NativeInfo {
private static final String RESTRICTION_ERROR_MESSAGE =
"This provider is restricted to native.java_binary, native.py_binary and native.java_test. "
+ "This is a ";
public static final String PROVIDER_NAME = "CcLauncherInfo";
public static final Provider PROVIDER = new Provider();
private final CcCompilationOutputs ccCompilationOutputs;
private final CcInfo ccInfo;
public CcLauncherInfo(CcInfo ccInfo, CcCompilationOutputs ccCompilationOutputs) {
this.ccInfo = ccInfo;
this.ccCompilationOutputs = ccCompilationOutputs;
}
@Override
public Provider getProvider() {
return PROVIDER;
}
public CcCompilationOutputs getCcCompilationOutputs(RuleContext ruleContext) {
checkRestrictedUsage(ruleContext);
return ccCompilationOutputs;
}
@VisibleForTesting
public CcCompilationOutputs getCcCompilationOutputsForTesting() {
return ccCompilationOutputs;
}
@StarlarkMethod(name = "compilation_outputs", documented = false, useStarlarkThread = true)
public CcCompilationOutputs getCcCompilationOutputsStarlark(StarlarkThread thread)
throws EvalException {
CcModule.checkPrivateStarlarkificationAllowlist(thread);
return ccCompilationOutputs;
}
public CcInfo getCcInfo(RuleContext ruleContext) {
checkRestrictedUsage(ruleContext);
return ccInfo;
}
@StarlarkMethod(name = "cc_info", documented = false, useStarlarkThread = true)
public CcInfo getCcInfoForStarlark(StarlarkThread thread) throws EvalException {
CcModule.checkPrivateStarlarkificationAllowlist(thread);
return ccInfo;
}
private void checkRestrictedUsage(RuleContext ruleContext) {
Rule rule = ruleContext.getRule();
if (rule.getRuleClassObject().isStarlark()
|| (!rule.getRuleClass().equals("java_binary")
&& !rule.getRuleClass().equals("java_test")
&& !rule.getRuleClass().equals("py_binary")
&& !rule.getRuleClass().equals("py_test"))) {
throw new IllegalStateException(RESTRICTION_ERROR_MESSAGE + rule.getRuleClass());
}
}
/** Provider class for {@link CcLauncherInfo} objects. */
public static class Provider extends BuiltinProvider<CcLauncherInfo> {
private Provider() {
super(PROVIDER_NAME, CcLauncherInfo.class);
}
}
}
private static RuntimeFiles collectRunfiles(
RuleContext ruleContext,
FeatureConfiguration featureConfiguration,
CcToolchainProvider toolchain,
List<LibraryToLink> libraries,
CcLinkingOutputs ccLibraryLinkingOutputs,
Link.LinkingMode linkingMode,
NestedSet<Artifact> transitiveArtifacts,
boolean linkCompileOutputSeparately)
throws RuleErrorException {
ImmutableList.Builder<Artifact> runtimeObjectsForCoverage = ImmutableList.builder();
Runfiles.Builder builder =
new Runfiles.Builder(
ruleContext.getWorkspaceName(),
ruleContext.getConfiguration().legacyExternalRunfiles());
Function<TransitiveInfoCollection, Runfiles> runfilesMapping =
CppHelper.runfilesFunction(ruleContext, linkingMode != Link.LinkingMode.DYNAMIC);
builder.add(ruleContext, runfilesMapping);
Runfiles.Builder coverageRuntimeObjectsBuilder =
new Runfiles.Builder(
ruleContext.getWorkspaceName(),
ruleContext.getConfiguration().legacyExternalRunfiles());
coverageRuntimeObjectsBuilder.add(ruleContext, runfilesMapping);
runtimeObjectsForCoverage.addAll(
coverageRuntimeObjectsBuilder.build().getAllArtifacts().toList());
runtimeObjectsForCoverage.addAll(LibraryToLink.getDynamicLibrariesForRuntime(true, libraries));
builder.addTransitiveArtifacts(transitiveArtifacts);
// Add the shared libraries to the runfiles. This adds any shared libraries that are in the
// srcs of this target.
builder.addArtifacts(LibraryToLink.getDynamicLibrariesForRuntime(true, libraries));
builder.addRunfiles(ruleContext, RunfilesProvider.DEFAULT_RUNFILES);
// TODO(plf): Why do we need .so files produced by cc_library in data dependencies of cc_binary?
// This can probably be removed safely.
for (TransitiveInfoCollection transitiveInfoCollection : ruleContext.getPrerequisites("data")) {
builder.merge(
CppHelper.runfilesFunction(ruleContext, /* linkingStatically= */ true)
.apply(transitiveInfoCollection));
builder.merge(
CppHelper.runfilesFunction(ruleContext, /* linkingStatically= */ false)
.apply(transitiveInfoCollection));
runtimeObjectsForCoverage.addAll(
CppHelper.runfilesFunction(ruleContext, /* linkingStatically= */ true)
.apply(transitiveInfoCollection)
.getAllArtifacts()
.toList());
runtimeObjectsForCoverage.addAll(
CppHelper.runfilesFunction(ruleContext, /* linkingStatically= */ false)
.apply(transitiveInfoCollection)
.getAllArtifacts()
.toList());
}
for (TransitiveInfoCollection transitiveInfoCollection :
ruleContext.getPrerequisites("dynamic_deps")) {
builder.merge(
transitiveInfoCollection.getProvider(RunfilesProvider.class).getDefaultRunfiles());
}
// Add the C++ runtime libraries if linking them dynamically.
if (linkingMode == Link.LinkingMode.DYNAMIC) {
try {
builder.addTransitiveArtifacts(toolchain.getDynamicRuntimeLinkInputs(featureConfiguration));
runtimeObjectsForCoverage.addAll(
toolchain.getDynamicRuntimeLinkInputs(featureConfiguration).toList());
} catch (EvalException e) {
throw ruleContext.throwWithRuleError(e);
}
}
if (linkCompileOutputSeparately) {
if (!ccLibraryLinkingOutputs.isEmpty()
&& ccLibraryLinkingOutputs.getLibraryToLink().getDynamicLibrary() != null) {
builder.addArtifact(ccLibraryLinkingOutputs.getLibraryToLink().getDynamicLibrary());
runtimeObjectsForCoverage.add(
ccLibraryLinkingOutputs.getLibraryToLink().getDynamicLibrary());
}
}
// For cc_binary and cc_test rules, there is an implicit dependency on
// the malloc library package, which is specified by the "malloc" attribute.
// As the BUILD encyclopedia says, the "malloc" attribute should be ignored
// if linkshared=1.
boolean linkshared = isLinkShared(ruleContext);
if (!linkshared) {
TransitiveInfoCollection malloc = CppHelper.mallocForTarget(ruleContext);
builder.addTarget(malloc, RunfilesProvider.DEFAULT_RUNFILES);
builder.addTarget(malloc, runfilesMapping);
}
return RuntimeFiles.create(builder.build(), runtimeObjectsForCoverage.build());
}
@AutoValue
abstract static class RuntimeFiles {
static RuntimeFiles create(
Runfiles runfiles, ImmutableList<Artifact> runtimeObjectsForCoverage) {
return new AutoValue_CcBinary_RuntimeFiles(runfiles, runtimeObjectsForCoverage);
}
abstract Runfiles runfiles();
abstract ImmutableList<Artifact> runtimeObjectsForCoverage();
}
@Override
@Nullable
public ConfiguredTarget create(RuleContext context)
throws InterruptedException, RuleErrorException, ActionConflictException {
RuleConfiguredTargetBuilder ruleBuilder = new RuleConfiguredTargetBuilder(context);
CcBinary.init(semantics, ruleBuilder, context);
return ruleBuilder.build();
}
public static void init(
CppSemantics semantics, RuleConfiguredTargetBuilder ruleBuilder, RuleContext ruleContext)
throws InterruptedException, RuleErrorException {
semantics.validateDeps(ruleContext);
if (ruleContext.attributes().isAttributeValueExplicitlySpecified("dynamic_deps")) {
if (!ruleContext
.getAnalysisEnvironment()
.getStarlarkSemantics()
.getBool(BuildLanguageOptions.EXPERIMENTAL_CC_SHARED_LIBRARY)) {
ruleContext.ruleError(
"The attribute 'dynamic_deps' can only be used with the flag"
+ " --experimental_cc_shared_library.");
} else if (ruleContext.attributes().isAttributeValueExplicitlySpecified("linkshared")) {
ruleContext.ruleError(
"Do not use `linkshared` to build a shared library. Use cc_shared_library instead.");
}
}
if (ruleContext.hasErrors()) {
fillInRequiredProviders(ruleBuilder, ruleContext);
return;
}
CcCommon common = new CcCommon(ruleContext);
common.reportInvalidOptions(ruleContext);
CcToolchainProvider ccToolchain = common.getToolchain();
ImmutableMap.Builder<String, String> toolchainMakeVariables = ImmutableMap.builder();
ccToolchain.addGlobalMakeVariables(toolchainMakeVariables);
ruleContext.initConfigurationMakeVariableContext(
new MapBackedMakeVariableSupplier(toolchainMakeVariables.buildOrThrow()),
new CcFlagsSupplier(ruleContext));
CppConfiguration cppConfiguration = ruleContext.getFragment(CppConfiguration.class);
PrecompiledFiles precompiledFiles = new PrecompiledFiles(ruleContext);
LinkTargetType linkType =
isLinkShared(ruleContext) ? LinkTargetType.DYNAMIC_LIBRARY : LinkTargetType.EXECUTABLE;
semantics.validateAttributes(ruleContext);
if (ruleContext.hasErrors()) {
fillInRequiredProviders(ruleBuilder, ruleContext);
return;
}
// if cc_binary includes "linkshared=1", then gcc will be invoked with
// linkopt "-shared", which causes the result of linking to be a shared
// library.
final Artifact binary;
// For linkshared=1 we used to force users to specify the file extension manually, as part of
// the target name.
// This is no longer necessary, the toolchain can figure out the correct file extension.
String targetName = ruleContext.getTarget().getName();
boolean hasLegacyLinkSharedName =
isLinkShared(ruleContext)
&& (CppFileTypes.SHARED_LIBRARY.matches(targetName)
|| CppFileTypes.VERSIONED_SHARED_LIBRARY.matches(targetName));
if (hasLegacyLinkSharedName) {
binary = ruleContext.getBinArtifact(PathFragment.create(targetName));
} else {
binary =
CppHelper.getLinkedArtifact(
ruleContext, ccToolchain, ruleContext.getConfiguration(), linkType);
}
LinkingMode linkingMode = getLinkStaticness(ruleContext, cppConfiguration);
ImmutableSet.Builder<String> requestedFeaturesBuilder = new ImmutableSet.Builder<>();
requestedFeaturesBuilder
.addAll(ruleContext.getFeatures())
.add(linkingMode == Link.LinkingMode.DYNAMIC ? DYNAMIC_LINKING_MODE : STATIC_LINKING_MODE);
ImmutableSet.Builder<String> disabledFeaturesBuilder = new ImmutableSet.Builder<>();
disabledFeaturesBuilder.addAll(ruleContext.getDisabledFeatures());
if (TargetUtils.isTestRule(ruleContext.getRule()) && cppConfiguration.useCcTestFeature()) {
requestedFeaturesBuilder.add(IS_CC_TEST_FEATURE_NAME);
disabledFeaturesBuilder.add(LEGACY_IS_CC_TEST_FEATURE_NAME);
}
FdoContext fdoContext = common.getFdoContext();
FeatureConfiguration featureConfiguration =
CcCommon.configureFeaturesOrReportRuleError(
ruleContext,
requestedFeaturesBuilder.build(),
/* unsupportedFeatures= */ disabledFeaturesBuilder.build(),
Language.CPP,
ccToolchain,
semantics);
ImmutableList<TransitiveInfoCollection> deps =
ImmutableList.<TransitiveInfoCollection>builder()
.addAll(ruleContext.getPrerequisites("deps"))
.add(CppHelper.mallocForTarget(ruleContext))
.build();
if (ruleContext.hasErrors()) {
fillInRequiredProviders(ruleBuilder, ruleContext);
return;
}
CcCompilationHelper compilationHelper =
new CcCompilationHelper(
ruleContext,
ruleContext,
ruleContext.getLabel(),
CppHelper.getGrepIncludes(ruleContext),
semantics,
featureConfiguration,
ccToolchain,
fdoContext,
TargetUtils.getExecutionInfo(
ruleContext.getRule(), ruleContext.isAllowTagsPropagation()),
/* shouldProcessHeaders= */ true)
.fromCommon(common, /* additionalCopts= */ ImmutableList.of())
.addPrivateHeaders(common.getPrivateHeaders())
.addSources(common.getSources())
.addCcCompilationContexts(CppHelper.getCompilationContextsFromDeps(deps))
.addCcCompilationContexts(
ImmutableList.of(CcCompilationHelper.getStlCcCompilationContext(ruleContext)))
.setHeadersCheckingMode(semantics.determineHeadersCheckingMode(ruleContext))
.setCodeCoverageEnabled(CcCompilationHelper.isCodeCoverageEnabled(ruleContext));
CompilationInfo compilationInfo = compilationHelper.compile(ruleContext);
CcCompilationContext ccCompilationContext = compilationInfo.getCcCompilationContext();
CcCompilationOutputs precompiledFileObjects =
CcCompilationOutputs.builder()
.addObjectFiles(precompiledFiles.getObjectFiles(/* usePic= */ false))
.addPicObjectFiles(precompiledFiles.getObjectFiles(/* usePic= */ true))
.build();
CcCompilationOutputs ccCompilationOutputs =
CcCompilationOutputs.builder()
.merge(precompiledFileObjects)
.merge(compilationInfo.getCcCompilationOutputs())
.build();
List<Artifact> additionalLinkerInputs = common.getAdditionalLinkerInputs();
// Allows the dynamic library generated for code of test targets to be linked separately.
boolean linkCompileOutputSeparately =
ruleContext.isTestTarget()
&& linkingMode == LinkingMode.DYNAMIC
&& cppConfiguration.getDynamicModeFlag() == DynamicMode.DEFAULT
&& ruleContext.getFeatures().contains(DYNAMIC_LINK_TEST_SRCS);
// When linking the object files directly into the resulting binary, we do not need
// library-level link outputs; thus, we do not let CcCompilationHelper produce link outputs
// (either shared object files or archives) for a non-library link type [*], and add
// the object files explicitly in determineLinkerArguments.
//
// When linking the object files into their own library, we want CcCompilationHelper to
// take care of creating the library link outputs for us, so we need to set the link
// type to STATIC_LIBRARY.
//
// [*] The only library link type is STATIC_LIBRARY. EXECUTABLE specifies a normal
// cc_binary output, while DYNAMIC_LIBRARY is a cc_binary rules that produces an
// output matching a shared object, for example cc_binary(name="foo.so", ...) on linux.
CcLinkingOutputs ccLinkingOutputs = CcLinkingOutputs.EMPTY;
if (linkCompileOutputSeparately && !ccCompilationOutputs.isEmpty()) {
CcLinkingHelper linkingHelper =
new CcLinkingHelper(
ruleContext,
ruleContext.getLabel(),
ruleContext,
ruleContext,
semantics,
featureConfiguration,
ccToolchain,
fdoContext,
ruleContext.getConfiguration(),
cppConfiguration,
ruleContext.getSymbolGenerator(),
TargetUtils.getExecutionInfo(
ruleContext.getRule(), ruleContext.isAllowTagsPropagation()))
.fromCommon(ruleContext, common)
.setGrepIncludes(CppHelper.getGrepIncludes(ruleContext))
.setIsStampingEnabled(AnalysisUtils.isStampingEnabled(ruleContext))
.setTestOrTestOnlyTarget(ruleContext.isTestTarget() || ruleContext.isTestOnlyTarget())
.addCcLinkingContexts(
CppHelper.getLinkingContextsFromDeps(
ImmutableList.of(CppHelper.mallocForTarget(ruleContext))))
.emitInterfaceSharedLibraries(true)
.setAlwayslink(false);
ccLinkingOutputs = linkingHelper.link(ccCompilationOutputs);
}
boolean isStaticMode = linkingMode != LinkingMode.DYNAMIC;
CcLinkingContext depsCcLinkingContext = collectCcLinkingContext(ruleContext);
Artifact generatedDefFile = null;
Artifact winDefFile = null;
if (isLinkShared(ruleContext)) {
if (featureConfiguration.isEnabled(CppRuleClasses.TARGETS_WINDOWS)) {
ImmutableList.Builder<Artifact> objectFiles = ImmutableList.builder();
objectFiles.addAll(ccCompilationOutputs.getObjectFiles(false));
for (LibraryToLink library : depsCcLinkingContext.getLibraries().toList()) {
if (isStaticMode
|| (library.getDynamicLibrary() == null && library.getInterfaceLibrary() == null)) {
if (library.getPicStaticLibrary() != null) {
if (library.getPicObjectFiles() != null) {
objectFiles.addAll(library.getPicObjectFiles());
}
} else if (library.getStaticLibrary() != null) {
if (library.getObjectFiles() != null) {
objectFiles.addAll(library.getObjectFiles());
}
}
}
}
Artifact defParser = common.getDefParser();
if (defParser != null) {
generatedDefFile =
CppHelper.createDefFileActions(
ruleContext, defParser, objectFiles.build(), binary.getFilename());
}
winDefFile =
CppHelper.getWindowsDefFileForLinking(
ruleContext, common.getWinDefFile(), generatedDefFile, featureConfiguration);
}
}
boolean usePic = usePic(ruleContext, ccToolchain, cppConfiguration, featureConfiguration);
// On Windows, if GENERATE_PDB_FILE feature is enabled
// then a pdb file will be built along with the executable.
Artifact pdbFile = null;
if (featureConfiguration.isEnabled(CppRuleClasses.GENERATE_PDB_FILE)) {
pdbFile =
ruleContext.getRelatedArtifact(
binary.getOutputDirRelativePath(
ruleContext.getConfiguration().isSiblingRepositoryLayout()),
".pdb");
}
NestedSetBuilder<CcLinkingContext.LinkerInput> extraLinkTimeLibrariesNestedSet =
NestedSetBuilder.linkOrder();
NestedSetBuilder<Artifact> extraLinkTimeRuntimeLibraries = NestedSetBuilder.linkOrder();
ExtraLinkTimeLibraries extraLinkTimeLibraries =
depsCcLinkingContext.getExtraLinkTimeLibraries();
if (extraLinkTimeLibraries != null) {
ExtraLinkTimeLibrary.BuildLibraryOutput extraLinkBuildLibraryOutput =
extraLinkTimeLibraries.buildLibraries(
ruleContext, linkingMode != LinkingMode.DYNAMIC, isLinkShared(ruleContext));
extraLinkTimeLibrariesNestedSet.addTransitive(extraLinkBuildLibraryOutput.getLinkerInputs());
extraLinkTimeRuntimeLibraries.addTransitive(
extraLinkBuildLibraryOutput.getRuntimeLibraries());
}
Pair<CcLinkingOutputs, CcLauncherInfo> ccLinkingOutputsAndCcLinkingInfo =
createTransitiveLinkingActions(
ruleContext,
ruleBuilder,
ccToolchain,
featureConfiguration,
fdoContext,
common,
precompiledFiles,
ccCompilationOutputs,
additionalLinkerInputs,
ccLinkingOutputs,
ccCompilationContext,
binary,
depsCcLinkingContext,
extraLinkTimeLibrariesNestedSet.build(),
linkCompileOutputSeparately,
semantics,
linkingMode,
cppConfiguration,
linkType,
pdbFile,
winDefFile);
if (ruleContext.hasErrors()) {
fillInRequiredProviders(ruleBuilder, ruleContext);
return;
}
CcLinkingOutputs ccLinkingOutputsBinary = ccLinkingOutputsAndCcLinkingInfo.first;
CcLauncherInfo ccLauncherInfo = ccLinkingOutputsAndCcLinkingInfo.second;
LibraryToLink ccLinkingOutputsBinaryLibrary = ccLinkingOutputsBinary.getLibraryToLink();
ImmutableList.Builder<LibraryToLink> librariesBuilder = ImmutableList.builder();
if (isLinkShared(ruleContext)) {
if (ccLinkingOutputsBinaryLibrary != null) {
librariesBuilder.add(ccLinkingOutputsBinaryLibrary);
}
}
// Also add all shared libraries from srcs.
for (Artifact library : precompiledFiles.getSharedLibraries()) {
Artifact symlink = common.getDynamicLibrarySymlink(library, true);
LibraryToLink libraryToLink =
LibraryToLink.builder()
.setLibraryIdentifier(CcLinkingOutputs.libraryIdentifierOf(library))
.setDynamicLibrary(symlink)
.setResolvedSymlinkDynamicLibrary(library)
.build();
librariesBuilder.add(libraryToLink);
}
ImmutableList<LibraryToLink> libraries = librariesBuilder.build();
NestedSet<Artifact> filesToBuild = NestedSetBuilder.create(Order.STABLE_ORDER, binary);
// Create the stripped binary, but don't add it to filesToBuild; it's only built when requested.
Artifact strippedFile = ruleContext.getImplicitOutputArtifact(
CppRuleClasses.CC_BINARY_STRIPPED);
CppHelper.createStripAction(
ruleContext, ccToolchain, cppConfiguration, binary, strippedFile, featureConfiguration);
NestedSet<Artifact> dwoFiles =
collectTransitiveDwoArtifacts(
ccCompilationOutputs,
CppHelper.mergeCcDebugInfoContexts(
compilationInfo.getCcCompilationOutputs(),
AnalysisUtils.getProviders(deps, CcInfo.PROVIDER)),
linkingMode,
usePic,
ccLinkingOutputsBinary.getAllLtoArtifacts());
Artifact dwpFile =
ruleContext.getImplicitOutputArtifact(CppRuleClasses.CC_BINARY_DEBUG_PACKAGE);
createDebugPackagerActions(ruleContext, ccToolchain, dwpFile, dwoFiles);
// The debug package should include the dwp file only if it was explicitly requested.
Artifact explicitDwpFile = dwpFile;
if (!ccToolchain.shouldCreatePerObjectDebugInfo(featureConfiguration, cppConfiguration)) {
explicitDwpFile = null;
} else {
// For cc_test rules, include the dwp in the runfiles if Fission is enabled and the test was
// built statically.
if (TargetUtils.isTestRule(ruleContext.getRule())
&& linkingMode != Link.LinkingMode.DYNAMIC
&& cppConfiguration.buildTestDwpIsActivated()) {
filesToBuild = NestedSetBuilder.fromNestedSet(filesToBuild).add(dwpFile).build();
}
}
// If the binary is linked dynamically and COPY_DYNAMIC_LIBRARIES_TO_BINARY is enabled, collect
// all the dynamic libraries we need at runtime. Then copy these libraries next to the binary.
NestedSet<Artifact> copiedRuntimeDynamicLibraries = null;
if (featureConfiguration.isEnabled(CppRuleClasses.COPY_DYNAMIC_LIBRARIES_TO_BINARY)) {
copiedRuntimeDynamicLibraries =
createDynamicLibrariesCopyActions(
ruleContext,
LibraryToLink.getDynamicLibrariesForRuntime(
isStaticMode, depsCcLinkingContext.getLibraries().toList()));
}
// TODO(bazel-team): Do we need to put original shared libraries (along with
// mangled symlinks) into the RunfilesSupport object? It does not seem
// logical since all symlinked libraries will be linked anyway and would
// not require manual loading but if we do, then we would need to collect
// their names and use a different constructor below.
NestedSetBuilder<Artifact> transitiveArtifacts =
NestedSetBuilder.<Artifact>stableOrder()
.addTransitive(filesToBuild)
.addTransitive(extraLinkTimeRuntimeLibraries.build());
if (featureConfiguration.isEnabled(CppRuleClasses.COPY_DYNAMIC_LIBRARIES_TO_BINARY)) {
transitiveArtifacts.addTransitive(copiedRuntimeDynamicLibraries);
}
ImmutableList.Builder<Artifact> runtimeObjectsForCoverage =
ImmutableList.<Artifact>builder().add(binary);
RuntimeFiles runtimeFiles =
collectRunfiles(
ruleContext,
featureConfiguration,
ccToolchain,
libraries,
ccLinkingOutputs,
linkingMode,
transitiveArtifacts.build(),
linkCompileOutputSeparately);
runtimeObjectsForCoverage.addAll(runtimeFiles.runtimeObjectsForCoverage());
RunfilesSupport runfilesSupport =
RunfilesSupport.withExecutable(ruleContext, runtimeFiles.runfiles(), binary);
addTransitiveInfoProviders(
ruleContext,
ccToolchain,
cppConfiguration,
featureConfiguration,
common,
ruleBuilder,
filesToBuild,
ccCompilationOutputs,
ccCompilationContext,
libraries,
runtimeObjectsForCoverage.build());
// Support test execution on darwin.
if (ApplePlatform.isApplePlatform(ccToolchain.getTargetCpu())
&& TargetUtils.isTestRule(ruleContext.getRule())) {
ruleBuilder.addNativeDeclaredProvider(
new ExecutionInfo(ImmutableMap.of(ExecutionRequirements.REQUIRES_DARWIN, "")));
}
// If PDB file is generated by the link action, we add it to pdb_file output group
if (pdbFile != null) {
ruleBuilder.addOutputGroup("pdb_file", pdbFile);
}
if (generatedDefFile != null) {
ruleBuilder.addOutputGroup("def_file", generatedDefFile);
}
if (!ccLinkingOutputsBinary.isEmpty()) {
LibraryToLink libraryToLink = ccLinkingOutputsBinary.getLibraryToLink();
Artifact dynamicLibraryForLinking = null;
if (libraryToLink.getInterfaceLibrary() != null) {
if (libraryToLink.getResolvedSymlinkInterfaceLibrary() != null) {
dynamicLibraryForLinking = libraryToLink.getResolvedSymlinkInterfaceLibrary();
} else {
dynamicLibraryForLinking = libraryToLink.getInterfaceLibrary();
}
} else if (libraryToLink.getDynamicLibrary() != null) {
if (libraryToLink.getResolvedSymlinkDynamicLibrary() != null) {
dynamicLibraryForLinking = libraryToLink.getResolvedSymlinkDynamicLibrary();
} else {
dynamicLibraryForLinking = libraryToLink.getDynamicLibrary();
}
}
if (dynamicLibraryForLinking != null) {
ruleBuilder.addOutputGroup("interface_library", dynamicLibraryForLinking);
}
}
if (copiedRuntimeDynamicLibraries != null) {
ruleBuilder.addOutputGroup("runtime_dynamic_libraries", copiedRuntimeDynamicLibraries);
}
CcStarlarkApiProvider.maybeAdd(ruleContext, ruleBuilder);
ruleBuilder
.addProvider(RunfilesProvider.class,
RunfilesProvider.simple(ruleContext, runtimeFiles.runfiles()))
.addNativeDeclaredProvider(
new DebugPackageProvider(ruleContext.getLabel(), strippedFile, binary, explicitDwpFile))
.setRunfilesSupport(runfilesSupport, binary)
.addNativeDeclaredProvider(ccLauncherInfo);
}
@Nullable
private static Pair<CcLinkingOutputs, CcLauncherInfo> createTransitiveLinkingActions(
RuleContext ruleContext,
RuleConfiguredTargetBuilder ruleBuilder,
CcToolchainProvider ccToolchain,
FeatureConfiguration featureConfiguration,
FdoContext fdoContext,
CcCommon common,
PrecompiledFiles precompiledFiles,
CcCompilationOutputs ccCompilationOutputs,
List<Artifact> additionalLinkerInputs,
CcLinkingOutputs ccLinkingOutputs,
CcCompilationContext ccCompilationContext,
Artifact binary,
CcLinkingContext depsCcLinkingContext,
NestedSet<CcLinkingContext.LinkerInput> extraLinkTimeLibraries,
boolean linkCompileOutputSeparately,
CppSemantics cppSemantics,
LinkingMode linkingMode,
CppConfiguration cppConfiguration,
LinkTargetType linkType,
Artifact pdbFile,
Artifact winDefFile)
throws InterruptedException, RuleErrorException {
CcCompilationOutputs.Builder ccCompilationOutputsBuilder =
CcCompilationOutputs.builder()
.addPicObjectFiles(ccCompilationOutputs.getObjectFiles(/* usePic= */ true))
.addObjectFiles(ccCompilationOutputs.getObjectFiles(/* usePic= */ false))
.addLtoCompilationContext(ccCompilationOutputs.getLtoCompilationContext());
CcCompilationOutputs ccCompilationOutputsWithOnlyObjects = ccCompilationOutputsBuilder.build();
CcLinkingHelper ccLinkingHelper =
new CcLinkingHelper(
ruleContext,
ruleContext.getLabel(),
ruleContext,
ruleContext,
cppSemantics,
featureConfiguration,
ccToolchain,
fdoContext,
ruleContext.getConfiguration(),
cppConfiguration,
ruleContext.getSymbolGenerator(),
TargetUtils.getExecutionInfo(
ruleContext.getRule(), ruleContext.isAllowTagsPropagation()))
.setGrepIncludes(CppHelper.getGrepIncludes(ruleContext))
.setIsStampingEnabled(AnalysisUtils.isStampingEnabled(ruleContext))
.setTestOrTestOnlyTarget(ruleContext.isTestTarget() || ruleContext.isTestOnlyTarget())
.addNonCodeLinkerInputs(additionalLinkerInputs);
CcInfo depsCcInfo = CcInfo.builder().setCcLinkingContext(depsCcLinkingContext).build();
CcLinkingContext.Builder currentCcLinkingContextBuilder = CcLinkingContext.builder();
if (linkCompileOutputSeparately) {
if (!ccLinkingOutputs.isEmpty()) {
currentCcLinkingContextBuilder.addLibrary(ccLinkingOutputs.getLibraryToLink());
}
ccCompilationOutputsWithOnlyObjects = CcCompilationOutputs.builder().build();
}
// Determine the libraries to link in.
// First libraries from srcs. Shared library artifacts here are substituted with mangled symlink
// artifacts generated by getDynamicLibraryLink(). This is done to minimize number of -rpath
// entries during linking process.
ImmutableList.Builder<LibraryToLink> precompiledLibraries = ImmutableList.builder();
for (Artifact library : precompiledFiles.getLibraries()) {
if (Link.SHARED_LIBRARY_FILETYPES.matches(library.getFilename())) {
LibraryToLink libraryToLink =
LibraryToLink.builder()
.setLibraryIdentifier(CcLinkingOutputs.libraryIdentifierOf(library))
.setDynamicLibrary(
common.getDynamicLibrarySymlink(library, /* preserveName= */ true))
.setResolvedSymlinkDynamicLibrary(library)
.build();
precompiledLibraries.add(libraryToLink);
} else if (Link.LINK_LIBRARY_FILETYPES.matches(library.getFilename())) {
LibraryToLink libraryToLink =
LibraryToLink.builder()
.setLibraryIdentifier(CcLinkingOutputs.libraryIdentifierOf(library))
.setStaticLibrary(library)
.setAlwayslink(true)
.build();
precompiledLibraries.add(libraryToLink);
} else if (Link.ARCHIVE_FILETYPES.matches(library.getFilename())) {
LibraryToLink libraryToLink =
LibraryToLink.builder()
.setLibraryIdentifier(CcLinkingOutputs.libraryIdentifierOf(library))
.setStaticLibrary(library)
.build();
precompiledLibraries.add(libraryToLink);
} else {
throw new IllegalStateException();
}
}
currentCcLinkingContextBuilder.addLibraries(precompiledLibraries.build());
ImmutableList.Builder<String> userLinkflags = ImmutableList.builder();
userLinkflags.addAll(common.getLinkopts());
currentCcLinkingContextBuilder
.setOwner(ruleContext.getLabel())
.addNonCodeInputs(ccCompilationContext.getTransitiveCompilationPrerequisites().toList())
.addNonCodeInputs(common.getLinkerScripts())
.addUserLinkFlags(
ImmutableList.of(
LinkOptions.of(userLinkflags.build(), ruleContext.getSymbolGenerator())));
CcInfo ccInfoWithoutExtraLinkTimeLibraries =
CcInfo.merge(
ImmutableList.of(
CcInfo.builder()
.setCcLinkingContext(currentCcLinkingContextBuilder.build())
.build(),
depsCcInfo));
CcInfo extraLinkTimeLibrariesCcInfo =
CcInfo.builder()
.setCcLinkingContext(
CcLinkingContext.builder()
.setOwner(ruleContext.getLabel())
.addTransitiveLinkerInputs(extraLinkTimeLibraries)
.build())
.build();
CcInfo ccInfo =
CcInfo.merge(
ImmutableList.of(ccInfoWithoutExtraLinkTimeLibraries, extraLinkTimeLibrariesCcInfo));
CcLinkingContext ccLinkingContext =
ruleContext.attributes().isAttributeValueExplicitlySpecified("dynamic_deps")
? filterLibrariesThatAreLinkedDynamically(
ruleContext, ruleBuilder, ccInfo.getCcLinkingContext(), cppSemantics)
: ccInfo.getCcLinkingContext();
if (ruleContext.hasErrors()) {
return null;
}
ccLinkingHelper
.addCcLinkingContexts(ImmutableList.of(ccLinkingContext))
.setUseTestOnlyFlags(ruleContext.isTestTarget())
.setShouldCreateStaticLibraries(false)
.setLinkingMode(linkingMode)
.setDynamicLinkType(linkType)
.setLinkerOutputArtifact(binary)
.setNeverLink(true)
.emitInterfaceSharedLibraries(
isLinkShared(ruleContext)
&& featureConfiguration.isEnabled(CppRuleClasses.TARGETS_WINDOWS)
&& CppHelper.useInterfaceSharedLibraries(
cppConfiguration, ccToolchain, featureConfiguration))
.setPdbFile(pdbFile);
ccLinkingHelper.setDefFile(winDefFile);
return Pair.of(
ccLinkingHelper.link(ccCompilationOutputsWithOnlyObjects),
new CcLauncherInfo(
ccInfoWithoutExtraLinkTimeLibraries, ccCompilationOutputsWithOnlyObjects));
}
/**
* Returns "true" if the {@code linkshared} attribute exists and is set.
*/
private static final boolean isLinkShared(RuleContext context) {
return context.attributes().has("linkshared", Type.BOOLEAN)
&& context.attributes().get("linkshared", Type.BOOLEAN);
}
private static final LinkingMode getLinkStaticness(
RuleContext context, CppConfiguration cppConfiguration) {
if (cppConfiguration.getDynamicModeFlag() == DynamicMode.FULLY) {
return LinkingMode.DYNAMIC;
} else if (cppConfiguration.getDynamicModeFlag() == DynamicMode.OFF
|| context.attributes().get("linkstatic", Type.BOOLEAN)) {
return LinkingMode.STATIC;
} else {
return LinkingMode.DYNAMIC;
}
}
/**
* Collects .dwo artifacts either transitively or directly, depending on the link type.
*
* <p>For a cc_binary, we only include the .dwo files corresponding to the .o files that are
* passed into the link. For static linking, this includes all transitive dependencies. But for
* dynamic linking, dependencies are separately linked into their own shared libraries, so we
* don't need them here.
*/
private static NestedSet<Artifact> collectTransitiveDwoArtifacts(
CcCompilationOutputs compilationOutputs,
CcDebugInfoContext ccDebugInfoContext,
LinkingMode linkingMode,
boolean usePic,
Iterable<LtoBackendArtifacts> ltoBackendArtifacts) {
NestedSetBuilder<Artifact> dwoFiles = NestedSetBuilder.stableOrder();
dwoFiles.addAll(
usePic ? compilationOutputs.getPicDwoFiles() : compilationOutputs.getDwoFiles());
if (ltoBackendArtifacts != null) {
for (LtoBackendArtifacts ltoBackendArtifact : ltoBackendArtifacts) {
if (ltoBackendArtifact.getDwoFile() != null) {
dwoFiles.add(ltoBackendArtifact.getDwoFile());
}
}
}
if (linkingMode != LinkingMode.DYNAMIC) {
dwoFiles.addTransitive(
usePic
? ccDebugInfoContext.getTransitivePicDwoFiles()
: ccDebugInfoContext.getTransitiveDwoFiles());
}
return dwoFiles.build();
}
/**
* Creates the actions needed to generate this target's "debug info package" (i.e. its .dwp file).
*/
private static void createDebugPackagerActions(
RuleContext context,
CcToolchainProvider toolchain,
Artifact dwpOutput,
NestedSet<Artifact> dwoFiles)
throws RuleErrorException {
// No inputs? Just generate a trivially empty .dwp.
//
// Note this condition automatically triggers for any build where fission is disabled.
// Because rules referencing .dwp targets may be invoked with or without fission, we need
// to support .dwp generation even when fission is disabled. Since no actual functionality
// is expected then, an empty file is appropriate.
if (dwoFiles.isEmpty()) {
context.registerAction(FileWriteAction.create(context, dwpOutput, "", false));
return;
}
// We apply a hierarchical action structure to limit the maximum number of inputs to any
// single action.
//
// While the dwp tool consumes .dwo files, it can also consume intermediate .dwp files,
// allowing us to split a large input set into smaller batches of arbitrary size and order.
// Aside from the parallelism performance benefits this offers, this also reduces input
// size requirements: if a.dwo, b.dwo, c.dwo, and e.dwo are each 1 KB files, we can apply
// two intermediate actions DWP(a.dwo, b.dwo) --> i1.dwp and DWP(c.dwo, e.dwo) --> i2.dwp.