JVM: allow -jvm-target 1.8 with -Xjdk-release=1.6

#KT-59098

compiler/cli/src/org/jetbrains/kotlin/cli/jvm/jvmArguments.kt

@@ -41,7 +41,7 @@ fun CompilerConfiguration.setupJvmSpecificArguments(arguments: K2JVMCompilerArgu
             if (value != getJavaVersion() || arguments.jdkHome != null) {
                 put(JVMConfigurationKeys.JDK_RELEASE, value)
             }
-            if (jvmTargetArg != null && jvmTargetArg != releaseTargetArg) {
+            if (jvmTargetArg != null && !isCompatibleJvmTargetAndRelease(jvmTargetArg, releaseTargetArg)) {
                 messageCollector.report(
                     ERROR,
                     "'-Xjdk-release=$releaseTargetArg' option conflicts with '-jvm-target $jvmTargetArg'. " +
@@ -110,6 +110,15 @@ fun CompilerConfiguration.setupJvmSpecificArguments(arguments: K2JVMCompilerArgu
     addAll(JVMConfigurationKeys.ADDITIONAL_JAVA_MODULES, arguments.additionalJavaModules?.asList())
 }
 
+private fun isCompatibleJvmTargetAndRelease(jvmTarget: String, release: String): Boolean {
+    if (jvmTarget == "1.8") {
+        // This is needed to be able to compile stdlib with -jvm-target 1.8 and -Xjdk-release=1.6/1.7.
+        return release in listOf("6", "1.6", "8", "1.8")
+    }
+
+    return jvmTarget == release
+}
+
 private fun CompilerConfiguration.handleClosureGenerationSchemeArgument(
     flag: String,
     value: String?,

compiler/testData/cli/jvm/jdkRelease.kt

@@ -1 +1,5 @@
-fun clear(byteByffer: java.nio.ByteBuffer) = byteByffer.clear()
+fun clear(byteByffer: java.nio.ByteBuffer) = byteByffer.clear()
+
+fun path(): java.nio.file.Path? = null
+
+fun stream() = java.util.stream.Stream.of(42)

compiler/testData/cli/jvm/jdkRelease6WithJvmTarget8Jdk11.args

@@ -0,0 +1,8 @@
+-Xjdk-release=1.6
+-jvm-target
+1.8
+-jdk-home
+$JDK_11_0
+$TESTDATA_DIR$/jdkRelease.kt
+-d
+$TEMP_DIR$

compiler/testData/cli/jvm/jdkRelease6WithJvmTarget8Jdk11.out

@@ -0,0 +1,7 @@
+compiler/testData/cli/jvm/jdkRelease.kt:3:22: error: unresolved reference 'file'.
+fun path(): java.nio.file.Path? = null
+                     ^^^^
+compiler/testData/cli/jvm/jdkRelease.kt:5:26: error: unresolved reference 'stream'.
+fun stream() = java.util.stream.Stream.of(42)
+                         ^^^^^^
+COMPILATION_ERROR

compiler/testData/cli/jvm/jdkRelease6WithJvmTarget8Jdk8.args

@@ -0,0 +1,8 @@
+-Xjdk-release=1.6
+-jvm-target
+1.8
+-jdk-home
+$JDK_1_8
+$TESTDATA_DIR$/jdkRelease.kt
+-d
+$TEMP_DIR$

compiler/testData/cli/jvm/jdkRelease6WithJvmTarget8Jdk8.out

@@ -0,0 +1,2 @@
+error: '-Xjdk-release=6' option is not supported by used JDK: $JDK_1_8
+COMPILATION_ERROR

compiler/tests-common/tests/org/jetbrains/kotlin/cli/AbstractCliTest.java

@@ -251,6 +251,9 @@ public abstract class AbstractCliTest extends TestCaseWithTmpdir {
             return null;
         }
 
+        if (arg.equals("$JDK_1_8")) return KtTestUtil.getJdk8Home().getAbsolutePath();
+        if (arg.equals("$JDK_11_0")) return KtTestUtil.getJdk11Home().getAbsolutePath();
+
         String argWithColonsReplaced = arg
                 .replace("\\:", "$COLON$")
                 .replace(":", File.pathSeparator)

compiler/tests-gen/org/jetbrains/kotlin/cli/CliTestGenerated.java

@@ -755,6 +755,16 @@ public class CliTestGenerated extends AbstractCliTest {
       runTest("compiler/testData/cli/jvm/jdkRelease.args");
     }
 
+    @TestMetadata("jdkRelease6WithJvmTarget8Jdk11.args")
+    public void testJdkRelease6WithJvmTarget8Jdk11() {
+      runTest("compiler/testData/cli/jvm/jdkRelease6WithJvmTarget8Jdk11.args");
+    }
+
+    @TestMetadata("jdkRelease6WithJvmTarget8Jdk8.args")
+    public void testJdkRelease6WithJvmTarget8Jdk8() {
+      runTest("compiler/testData/cli/jvm/jdkRelease6WithJvmTarget8Jdk8.args");
+    }
+
     @TestMetadata("jdkRelease6WithoutExplicitJvmTarget.args")
     public void testJdkRelease6WithoutExplicitJvmTarget() {
       runTest("compiler/testData/cli/jvm/jdkRelease6WithoutExplicitJvmTarget.args");