Support for C++ source compatibility

subprojects/language-native/src/integTest/groovy/org/gradle/language/cpp/CppApplicationIntegrationTest.groovy

@@ -26,6 +26,7 @@ import org.gradle.nativeplatform.fixtures.app.CppAppWithLibraryAndOptionalFeatur
 import org.gradle.nativeplatform.fixtures.app.CppAppWithOptionalFeature
 import org.gradle.nativeplatform.fixtures.app.CppCompilerDetectingTestApp
 import org.gradle.nativeplatform.fixtures.app.SourceElement
+import spock.lang.Unroll
 
 import static org.gradle.util.Matchers.containsText
 
@@ -1033,4 +1034,85 @@ class CppApplicationIntegrationTest extends AbstractCppIntegrationTest implement
         executable("build/exe/main/debug/app").assertExists()
         installation("build/install/main/debug").exec().out == app.expectedOutput(toolChain)
     }
+
+    @RequiresInstalledToolChain(ToolChainRequirement.GCC_COMPATIBLE)
+    @Unroll
+    def "build fails when cpp source uses language features outside the requested source compatibility"() {
+        given:
+        buildFile << """
+            apply plugin: 'cpp-application'
+
+            application {
+                binaries.configureEach {
+                    sourceCompatibility = CppSourceCompatibility.${sourceCompatibility}
+                }
+            }
+         """
+
+        and:
+        file("src/main/cpp/cpp11.cpp") << """
+            #include <iostream>
+            #include <ctime>
+            #include <chrono>
+            int main () {
+              using namespace std::chrono;
+              system_clock::time_point today = system_clock::now();
+              time_t tt;
+              tt = system_clock::to_time_t ( today );
+              std::cout << "today is: " << ctime(&tt);
+              return 0;
+            }
+"""
+
+        expect:
+        if (shouldFail) {
+            fails "assemble"
+            failure.assertHasDescription("Execution failed for task ':compileDebugCpp'.")
+            failure.assertHasCause("A build operation failed.")
+            failure.assertThatCause(containsText("C++ compiler failed while compiling cpp11.cpp"))
+        } else {
+            succeeds "assemble"
+        }
+
+        where:
+        sourceCompatibility || shouldFail 
+        'Cpp11'             || false
+        'Cpp98'             || true
+    }
+
+    @RequiresInstalledToolChain(ToolChainRequirement.GCC_COMPATIBLE)
+    def "recompile when source compatibility changes"() {
+        when:
+        buildFile << """
+            apply plugin: 'cpp-application'
+
+            application {
+                binaries.configureEach {
+                    sourceCompatibility = CppSourceCompatibility.Cpp98
+                }
+            }
+         """
+
+        and:
+        file("src/main/cpp/main.cpp") << """
+            int main () {
+              return 0;
+            }
+"""
+
+        then:
+        succeeds "assemble"
+
+        when:
+        buildFile << """
+            application {
+                binaries.configureEach {
+                    sourceCompatibility = CppSourceCompatibility.Cpp11
+                }
+            }
+         """
+
+        then:
+        executedAndNotSkipped(":assemble")
+    }
 }

subprojects/language-native/src/integTest/groovy/org/gradle/language/cpp/CppLibraryIntegrationTest.groovy

@@ -24,6 +24,7 @@ import org.gradle.nativeplatform.fixtures.app.CppGreeterWithOptionalFeature
 import org.gradle.nativeplatform.fixtures.app.CppLib
 import org.gradle.nativeplatform.fixtures.app.SourceElement
 import org.hamcrest.Matchers
+import spock.lang.Unroll
 
 import static org.gradle.util.Matchers.containsText
 
@@ -569,4 +570,49 @@ project(':greeter') {
         result.assertTasksExecuted(tasks.debug.allToLink, ":assemble")
         sharedLibrary("build/lib/main/debug/hello").assertExists()
     }
+
+    @RequiresInstalledToolChain(ToolChainRequirement.GCC_COMPATIBLE)
+    @Unroll
+    def "build fails when cpp source uses language features outside the requested source compatibility"() {
+        given:
+        buildFile << """
+            apply plugin: 'cpp-library'
+
+            library {
+                binaries.configureEach {
+                    sourceCompatibility = CppSourceCompatibility.${sourceCompatibility}
+                }
+            }
+         """
+
+        and:
+        file("src/main/cpp/cpp11.cpp") << """
+            #include <iostream>
+            #include <ctime>
+            #include <chrono>
+            int main () {
+              using namespace std::chrono;
+              system_clock::time_point today = system_clock::now();
+              time_t tt;
+              tt = system_clock::to_time_t ( today );
+              std::cout << "today is: " << ctime(&tt);
+              return 0;
+            }
+"""
+
+        expect:
+        if (shouldFail) {
+            fails "assemble"
+            failure.assertHasDescription("Execution failed for task ':compileDebugCpp'.")
+            failure.assertHasCause("A build operation failed.")
+            failure.assertThatCause(containsText("C++ compiler failed while compiling cpp11.cpp"))
+        } else {
+            succeeds "assemble"
+        }
+
+        where:
+        sourceCompatibility || shouldFail 
+        'Cpp11'             || false
+        'Cpp98'             || true
+    }
 }

subprojects/language-native/src/main/java/org/gradle/language/cpp/CppBinary.java

@@ -18,12 +18,13 @@
 
 import org.gradle.api.Incubating;
 import org.gradle.api.attributes.Attribute;
+import org.gradle.api.component.BuildableComponent;
 import org.gradle.api.file.FileCollection;
 import org.gradle.api.provider.Provider;
-import org.gradle.api.component.BuildableComponent;
 import org.gradle.language.ComponentWithDependencies;
 import org.gradle.language.cpp.tasks.CppCompile;
 import org.gradle.language.nativeplatform.ComponentWithObjectFiles;
+import org.gradle.nativeplatform.CppSourceCompatibility;
 import org.gradle.nativeplatform.Linkage;
 
 /**
@@ -85,4 +86,11 @@ public interface CppBinary extends ComponentWithObjectFiles, ComponentWithDepend
      * @since 4.5
      */
     Provider<CppCompile> getCompileTask();
+
+    /**
+     * Returns the C++ source compatibility to use to compile the source files.
+     *
+     * @since 5.2
+     */
+    Provider<CppSourceCompatibility> getSourceCompatibility();
 }

subprojects/language-native/src/main/java/org/gradle/language/cpp/CppComponent.java

@@ -27,6 +27,7 @@
 import org.gradle.language.BinaryCollection;
 import org.gradle.language.ComponentWithBinaries;
 import org.gradle.language.ComponentWithDependencies;
+import org.gradle.nativeplatform.CppSourceCompatibility;
 import org.gradle.nativeplatform.TargetMachine;
 
 /**
@@ -107,4 +108,11 @@ public interface CppComponent extends ComponentWithBinaries, ComponentWithDepend
      * @since 5.1
      */
     SetProperty<TargetMachine> getTargetMachines();
+
+    /**
+     * Returns the C++ source compatibility for this component.
+     *
+     * @since 5.2
+     */
+    Property<CppSourceCompatibility> getSourceCompatibility();
 }

subprojects/language-native/src/main/java/org/gradle/language/cpp/internal/DefaultCppBinary.java

@@ -37,6 +37,7 @@
 import org.gradle.language.cpp.tasks.CppCompile;
 import org.gradle.language.internal.DefaultNativeBinary;
 import org.gradle.language.nativeplatform.internal.Names;
+import org.gradle.nativeplatform.CppSourceCompatibility;
 import org.gradle.nativeplatform.MachineArchitecture;
 import org.gradle.nativeplatform.OperatingSystemFamily;
 import org.gradle.nativeplatform.toolchain.internal.NativeToolChainInternal;
@@ -59,6 +60,7 @@ public class DefaultCppBinary extends DefaultNativeBinary implements CppBinary {
     private final Configuration includePathConfiguration;
     private final Property<CppCompile> compileTaskProperty;
     private final NativeVariantIdentity identity;
+    private final Property<CppSourceCompatibility> sourceCompatibility;
 
     public DefaultCppBinary(Names names, ObjectFactory objects, Provider<String> baseName, FileCollection sourceFiles, FileCollection componentHeaderDirs, ConfigurationContainer configurations, Configuration componentImplementation, CppPlatform targetPlatform, NativeToolChainInternal toolChain, PlatformToolProvider platformToolProvider, NativeVariantIdentity identity) {
         super(names, objects, componentImplementation);
@@ -69,6 +71,7 @@ public DefaultCppBinary(Names names, ObjectFactory objects, Provider<String> bas
         this.platformToolProvider = platformToolProvider;
         this.compileTaskProperty = objects.property(CppCompile.class);
         this.identity = identity;
+        this.sourceCompatibility = objects.property(CppSourceCompatibility.class);
 
         // TODO - reduce duplication with Swift binary
 
@@ -178,6 +181,11 @@ public Property<CppCompile> getCompileTask() {
         return compileTaskProperty;
     }
 
+    @Override
+    public Property<CppSourceCompatibility> getSourceCompatibility() {
+        return sourceCompatibility;
+    }
+
     public PlatformToolProvider getPlatformToolProvider() {
         return platformToolProvider;
     }

subprojects/language-native/src/main/java/org/gradle/language/cpp/internal/DefaultCppComponent.java

@@ -32,6 +32,7 @@
 import org.gradle.language.nativeplatform.internal.ComponentWithNames;
 import org.gradle.language.nativeplatform.internal.DefaultNativeComponent;
 import org.gradle.language.nativeplatform.internal.Names;
+import org.gradle.nativeplatform.CppSourceCompatibility;
 import org.gradle.nativeplatform.TargetMachine;
 
 import javax.inject.Inject;
@@ -48,6 +49,7 @@ public abstract class DefaultCppComponent extends DefaultNativeComponent impleme
     private final Names names;
     private final DefaultBinaryCollection<CppBinary> binaries;
     private final SetProperty<TargetMachine> targetMachines;
+    private final Property<CppSourceCompatibility> srcCompat;
 
     @Inject
     public DefaultCppComponent(String name, FileOperations fileOperations, ObjectFactory objectFactory) {
@@ -61,6 +63,7 @@ public DefaultCppComponent(String name, FileOperations fileOperations, ObjectFac
         names = Names.of(name);
         binaries = Cast.uncheckedCast(objectFactory.newInstance(DefaultBinaryCollection.class, CppBinary.class));
         targetMachines = objectFactory.setProperty(TargetMachine.class);
+        srcCompat = objectFactory.property(CppSourceCompatibility.class);
     }
 
     @Override
@@ -128,4 +131,9 @@ public DefaultBinaryCollection<CppBinary> getBinaries() {
     public SetProperty<TargetMachine> getTargetMachines() {
         return targetMachines;
     }
+
+    @Override
+    public Property<CppSourceCompatibility> getSourceCompatibility() {
+        return srcCompat;
+    }
 }

subprojects/language-native/src/main/java/org/gradle/language/cpp/plugins/CppBasePlugin.java

@@ -37,13 +37,19 @@
 import org.gradle.language.cpp.tasks.CppCompile;
 import org.gradle.language.nativeplatform.internal.Names;
 import org.gradle.language.plugins.NativeBasePlugin;
+import org.gradle.nativeplatform.CppSourceCompatibility;
 import org.gradle.nativeplatform.platform.NativePlatform;
 import org.gradle.nativeplatform.toolchain.internal.NativeToolChainInternal;
 import org.gradle.nativeplatform.toolchain.internal.PlatformToolProvider;
 import org.gradle.nativeplatform.toolchain.internal.ToolType;
+import org.gradle.nativeplatform.toolchain.internal.clang.ClangVersionCppSourceCompatibilitySupport;
+import org.gradle.nativeplatform.toolchain.internal.gcc.GccVersionCppSourceCompatibilitySupport;
+import org.gradle.nativeplatform.toolchain.internal.gcc.metadata.GccMetadata;
+import org.gradle.nativeplatform.toolchain.internal.metadata.CompilerMetadata;
 import org.gradle.nativeplatform.toolchain.internal.plugins.StandardToolChainsPlugin;
 import org.gradle.swiftpm.internal.NativeProjectPublication;
 import org.gradle.swiftpm.internal.SwiftPmTarget;
+import org.gradle.util.VersionNumber;
 
 import javax.inject.Inject;
 import java.io.File;
@@ -112,6 +118,7 @@ public void execute(CppCompile compile) {
                         compile.getTargetPlatform().set(currentPlatform);
                         compile.getToolChain().set(toolChain);
                         compile.getObjectFileDir().set(buildDirectory.dir("obj/" + names.getDirName()));
+                        compile.getSourceCompatibility().set(binary.getSourceCompatibility());
 
                         if (binary instanceof CppSharedLibrary) {
                             compile.setPositionIndependentCode(true);
@@ -129,6 +136,39 @@ public Provider<? extends Directory> transform(CppCompile cppCompile) {
             }
         });
 
+        project.getComponents().withType(DefaultCppComponent.class, new Action<DefaultCppComponent>() {
+            @Override
+            public void execute(DefaultCppComponent component) {
+                component.getBinaries().whenElementKnown(DefaultCppBinary.class, new Action<DefaultCppBinary>() {
+                    @Override
+                    public void execute(DefaultCppBinary binary) {
+                        Provider<CppSourceCompatibility> cppSourceCompatibilityProvider = project.provider(new Callable<CppSourceCompatibility>() {
+                            @Override
+                            public CppSourceCompatibility call() throws Exception {
+                                component.getSourceCompatibility().finalizeValue();
+                                CppSourceCompatibility cppSourceCompatibility = component.getSourceCompatibility().getOrNull();
+                                if (cppSourceCompatibility == null) {
+                                    CompilerMetadata compilerMetadata = binary.getPlatformToolProvider().getCompilerMetadata(ToolType.CPP_COMPILER);
+                                    if (compilerMetadata instanceof GccMetadata) {
+                                        VersionNumber version = compilerMetadata.getVersion();
+                                        String vendor = compilerMetadata.getVendor().toLowerCase();
+                                        if (vendor.contains("clang")) {
+                                            return ClangVersionCppSourceCompatibilitySupport.getDefaultSourceCompatibility();
+                                        }
+                                        return GccVersionCppSourceCompatibilitySupport.getDefaultSourceCompatibility(version);
+                                    }
+                                    // TODO: VisualStudio support for CppSourceCompatibility
+                                }
+                                return cppSourceCompatibility;
+                            }
+                        });
+
+                        binary.getSourceCompatibility().set(cppSourceCompatibilityProvider);
+                    }
+                });
+            }
+        });
+
         project.getComponents().withType(ProductionCppComponent.class, new Action<ProductionCppComponent>() {
             @Override
             public void execute(final ProductionCppComponent component) {

subprojects/language-native/src/main/java/org/gradle/language/cpp/tasks/CppCompile.java

@@ -16,20 +16,47 @@
 package org.gradle.language.cpp.tasks;
 
 import org.gradle.api.Incubating;
+import org.gradle.api.model.ObjectFactory;
+import org.gradle.api.provider.Property;
 import org.gradle.api.tasks.CacheableTask;
+import org.gradle.api.tasks.Input;
+import org.gradle.api.tasks.Optional;
 import org.gradle.language.cpp.tasks.internal.DefaultCppCompileSpec;
 import org.gradle.language.nativeplatform.tasks.AbstractNativeSourceCompileTask;
+import org.gradle.nativeplatform.CppSourceCompatibility;
 import org.gradle.nativeplatform.toolchain.internal.NativeCompileSpec;
 
+import javax.inject.Inject;
+
 /**
  * Compiles C++ source files into object files.
  */
 @Incubating
 @CacheableTask
 public class CppCompile extends AbstractNativeSourceCompileTask {
+    private final Property<CppSourceCompatibility> srcCompat;
+
+    @Inject
+    public CppCompile(ObjectFactory objectFactory) {
+        srcCompat = objectFactory.property(CppSourceCompatibility.class);
+    }
+
+    /**
+     * Returns the source compatibility that augments the C++ compilers arguments.
+     *
+     * @return C++ source compatibility.
+     * @since 5.2
+     */
+    @Input
+    @Optional
+    public Property<CppSourceCompatibility> getSourceCompatibility() {
+        return srcCompat;
+    }
+
     @Override
     protected NativeCompileSpec createCompileSpec() {
-        return new DefaultCppCompileSpec();
+        DefaultCppCompileSpec defaultCppCompileSpec = new DefaultCppCompileSpec();
+        defaultCppCompileSpec.setSourceCompatibility(srcCompat.getOrNull());
+        return defaultCppCompileSpec;
     }
-
 }