Remove functionality to implement parse_headers via building a C++ mo…

…dule. This

has never been used and is not worth keeping around.

RELNOTES: None.
PiperOrigin-RevId: 351452688

src/main/java/com/google/devtools/build/lib/rules/cpp/CcCompilationContext.java

@@ -90,7 +90,6 @@ public final class CcCompilationContext implements CcCompilationContextApi<Artif
   private final NestedSet<Artifact> transitivePicModules;
 
   private final CppModuleMap cppModuleMap;
-  private final CppModuleMap verificationModuleMap;
 
   private final boolean propagateModuleMapAsActionInput;
 
@@ -129,7 +128,6 @@ public final class CcCompilationContext implements CcCompilationContextApi<Artif
       ImmutableList<Artifact> directModuleMaps,
       ImmutableList<CppModuleMap> exportingModuleMaps,
       CppModuleMap cppModuleMap,
-      @Nullable CppModuleMap verificationModuleMap,
       boolean propagateModuleMapAsActionInput,
       CppConfiguration.HeadersCheckingMode headersCheckingMode,
       NestedSet<Pair<String, String>> virtualToOriginalHeaders) {
@@ -144,7 +142,6 @@ public final class CcCompilationContext implements CcCompilationContextApi<Artif
     this.transitivePicModules = transitivePicModules;
     this.cppModuleMap = cppModuleMap;
     this.nonCodeInputs = nonCodeInputs;
-    this.verificationModuleMap = verificationModuleMap;
     this.compilationPrerequisites = compilationPrerequisites;
     this.propagateModuleMapAsActionInput = propagateModuleMapAsActionInput;
     this.headersCheckingMode = headersCheckingMode;
@@ -582,7 +579,6 @@ public static CcCompilationContext disallowUndeclaredHeaders(
         ccCompilationContext.directModuleMaps,
         ccCompilationContext.exportingModuleMaps,
         ccCompilationContext.cppModuleMap,
-        ccCompilationContext.verificationModuleMap,
         ccCompilationContext.propagateModuleMapAsActionInput,
         ccCompilationContext.headersCheckingMode,
         ccCompilationContext.virtualToOriginalHeaders);
@@ -593,11 +589,6 @@ public CppModuleMap getCppModuleMap() {
     return cppModuleMap;
   }
 
-  /** @return the C++ module map of the owner. */
-  public CppModuleMap getVerificationModuleMap() {
-    return verificationModuleMap;
-  }
-
   /** Returns the list of dependencies' C++ module maps re-exported by this compilation context. */
   public ImmutableList<CppModuleMap> getExportingModuleMaps() {
     return exportingModuleMaps;
@@ -689,7 +680,6 @@ public static class Builder {
     private final TransitiveSetHelper<String> defines = new TransitiveSetHelper<>();
     private final Set<String> localDefines = new LinkedHashSet<>();
     private CppModuleMap cppModuleMap;
-    private CppModuleMap verificationModuleMap;
     private boolean propagateModuleMapAsActionInput = true;
     private CppConfiguration.HeadersCheckingMode headersCheckingMode =
         CppConfiguration.HeadersCheckingMode.STRICT;
@@ -944,12 +934,6 @@ public Builder setCppModuleMap(CppModuleMap cppModuleMap) {
       return this;
     }
 
-    /** Sets the C++ module map used to verify that headers are modules compatible. */
-    public Builder setVerificationModuleMap(CppModuleMap verificationModuleMap) {
-      this.verificationModuleMap = verificationModuleMap;
-      return this;
-    }
-
     /** Causes the module map to be passed as an action input to dependant compilations. */
     public Builder setPropagateCppModuleMapAsActionInput(boolean propagateModuleMap) {
       this.propagateModuleMapAsActionInput = propagateModuleMap;
@@ -1020,7 +1004,6 @@ public CcCompilationContext build(ActionOwner owner, MiddlemanFactory middlemanF
           ImmutableList.copyOf(directModuleMaps),
           ImmutableList.copyOf(exportingModuleMaps),
           cppModuleMap,
-          verificationModuleMap,
           propagateModuleMapAsActionInput,
           headersCheckingMode,
           virtualToOriginalHeaders.build());

src/main/java/com/google/devtools/build/lib/rules/cpp/CcCompilationHelper.java

@@ -1049,8 +1049,7 @@ private CcCompilationContext initializeCcCompilationContext(RuleContext ruleCont
     if (featureConfiguration.isEnabled(CppRuleClasses.MODULE_MAPS)) {
       if (cppModuleMap == null) {
         cppModuleMap =
-            CppHelper.createDefaultCppModuleMap(
-                actionConstructionContext, configuration, label, /*suffix=*/ "");
+            CppHelper.createDefaultCppModuleMap(actionConstructionContext, configuration, label);
       }
 
       ccCompilationContextBuilder.setPropagateCppModuleMapAsActionInput(
@@ -1083,21 +1082,6 @@ private CcCompilationContext initializeCcCompilationContext(RuleContext ruleCont
       if (getGeneratesNoPicHeaderModule()) {
         ccCompilationContextBuilder.setHeaderModule(getHeaderModule(cppModuleMap.getArtifact()));
       }
-      if (!compiled
-          && featureConfiguration.isEnabled(CppRuleClasses.PARSE_HEADERS)
-          && featureConfiguration.isEnabled(CppRuleClasses.USE_HEADER_MODULES)
-          && cppConfiguration.getParseHeadersVerifiesModules()) {
-        // Here, we are creating a compiled module to verify that headers are self-contained and
-        // modules ready, but we don't use the corresponding module map or compiled file anywhere
-        // else.
-        CppModuleMap verificationMap =
-            CppHelper.createDefaultCppModuleMap(
-                actionConstructionContext, configuration, label, /*suffix=*/ ".verify");
-        actionRegistry.registerAction(
-            createModuleMapAction(
-                verificationMap, publicHeaders, dependentModuleMaps, /*compiledModule=*/ true));
-        ccCompilationContextBuilder.setVerificationModuleMap(verificationMap);
-      }
     }
     ccCompilationContextBuilder.setPurpose(purpose);
     return ccCompilationContextBuilder.build();
@@ -1352,12 +1336,6 @@ private CcCompilationOutputs createCcCompileActions() throws RuleErrorException
           createModuleCodegenAction(result, moduleMapLabel, module);
         }
       }
-    } else if (ccCompilationContext.getVerificationModuleMap() != null) {
-      Collection<Artifact> modules =
-          createModuleAction(result, ccCompilationContext.getVerificationModuleMap());
-      for (Artifact module : modules) {
-        result.addHeaderTokenFile(module);
-      }
     }
 
     ImmutableMap<Artifact, String> outputNameMap;

src/main/java/com/google/devtools/build/lib/rules/cpp/CcToolchainProvider.java

@@ -342,10 +342,7 @@ public boolean supportsHeaderParsing() {
    */
   public boolean shouldProcessHeaders(
       FeatureConfiguration featureConfiguration, CppConfiguration cppConfiguration) {
-    // If parse_headers_verifies_modules is switched on, we verify that headers are
-    // self-contained by building the module instead.
-    return !cppConfiguration.getParseHeadersVerifiesModules()
-        && featureConfiguration.isEnabled(CppRuleClasses.PARSE_HEADERS);
+    return featureConfiguration.isEnabled(CppRuleClasses.PARSE_HEADERS);
   }
 
   @Override

src/main/java/com/google/devtools/build/lib/rules/cpp/CppCompileActionBuilder.java

@@ -163,14 +163,12 @@ public String getActionName() {
       return CppActionNames.CPP_MODULE_COMPILE;
     } else if (CppFileTypes.CPP_HEADER.matches(sourcePath)) {
       // TODO(bazel-team): Handle C headers that probably don't work in C++ mode.
-      if (!cppConfiguration.getParseHeadersVerifiesModules()
-          && featureConfiguration.isEnabled(CppRuleClasses.PARSE_HEADERS)) {
+      if (featureConfiguration.isEnabled(CppRuleClasses.PARSE_HEADERS)) {
         return CppActionNames.CPP_HEADER_PARSING;
-      } else {
-        // CcCommon.collectCAndCppSources() ensures we do not add headers to
-        // the compilation artifacts unless 'parse_headers' is set.
-        throw new IllegalStateException();
       }
+      // CcCommon.collectCAndCppSources() ensures we do not add headers to
+      // the compilation artifacts unless 'parse_headers' is set.
+      throw new IllegalStateException();
     } else if (CppFileTypes.C_SOURCE.matches(sourcePath)) {
       return CppActionNames.C_COMPILE;
     } else if (CppFileTypes.CPP_SOURCE.matches(sourcePath)) {

src/main/java/com/google/devtools/build/lib/rules/cpp/CppConfiguration.java

@@ -441,10 +441,6 @@ public boolean getInmemoryDotdFiles() {
     return cppOptions.inmemoryDotdFiles;
   }
 
-  public boolean getParseHeadersVerifiesModules() {
-    return cppOptions.parseHeadersVerifiesModules;
-  }
-
   public boolean getParseHeadersSkippedIfCorrespondingSrcsFound() {
     return cppOptions.parseHeadersSkippedIfCorrespondingSrcsFound;
   }

src/main/java/com/google/devtools/build/lib/rules/cpp/CppHelper.java

@@ -567,14 +567,12 @@ public static boolean usePicForBinaries(
   public static CppModuleMap createDefaultCppModuleMap(
       ActionConstructionContext actionConstructionContext,
       BuildConfiguration configuration,
-      Label label,
-      String suffix) {
+      Label label) {
     // Create the module map artifact as a genfile.
     Artifact mapFile =
         actionConstructionContext.getPackageRelativeArtifact(
             PathFragment.create(
                 label.getName()
-                    + suffix
                     + Iterables.getOnlyElement(CppFileTypes.CPP_MODULE_MAP.getExtensions())),
             configuration.getGenfilesDirectory(label.getRepository()));
     return new CppModuleMap(mapFile, label.toString());

src/main/java/com/google/devtools/build/lib/rules/cpp/CppOptions.java

@@ -731,17 +731,6 @@ public Label getPropellerOptimizeLabel() {
   )
   public boolean inmemoryDotdFiles;
 
-  @Option(
-    name = "parse_headers_verifies_modules",
-    defaultValue = "false",
-    documentationCategory = OptionDocumentationCategory.BUILD_TIME_OPTIMIZATION,
-    effectTags = {OptionEffectTag.LOADING_AND_ANALYSIS, OptionEffectTag.CHANGES_INPUTS},
-    help =
-        "If enabled, the parse_headers feature verifies that a header module can be built for the "
-            + "target in question instead of doing a separate compile of the header."
-  )
-  public boolean parseHeadersVerifiesModules;
-
   @Option(
       name = "experimental_parse_headers_skipped_if_corresponding_srcs_found",
       defaultValue = "false",