Initial commit with full minimal test case

ParameterPrintingProcessor.java

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+import javax.annotation.processing.AbstractProcessor;
+import javax.annotation.processing.RoundEnvironment;
+import javax.annotation.processing.SupportedAnnotationTypes;
+import javax.annotation.processing.SupportedSourceVersion;
+import javax.lang.model.SourceVersion;
+import javax.lang.model.element.*;
+import javax.lang.model.type.DeclaredType;
+import javax.lang.model.type.TypeKind;
+import javax.lang.model.type.TypeMirror;
+import javax.tools.Diagnostic;
+import java.util.List;
+import java.util.Set;
+
+@SupportedAnnotationTypes("javax.annotation.processing.SupportedSourceVersion")
+public class ParameterPrintingProcessor extends AbstractProcessor {
+    @Override
+    public SourceVersion getSupportedSourceVersion() {
+        return SourceVersion.latestSupported();
+    }
+
+    @Override
+    public boolean process(final Set<? extends TypeElement> annotations, final RoundEnvironment roundEnv) {
+        if (annotations.isEmpty() || roundEnv.processingOver())
+            return false; // done
+        for (final Element element : roundEnv.getElementsAnnotatedWith(SupportedSourceVersion.class)) {
+            for(final Element method : ((TypeElement) element).getEnclosedElements()) {
+                if(method.getKind() != ElementKind.METHOD)
+                    continue;
+                final TypeMirror returnType = ((ExecutableElement)method).getReturnType();
+                if(returnType.getKind() != TypeKind.DECLARED)
+                    continue;
+                final List<? extends Element> methodsAndConstructors = ((TypeElement) ((DeclaredType) returnType).asElement()).getEnclosedElements();
+                processingEnv.getMessager().printMessage(Diagnostic.Kind.MANDATORY_WARNING,
+                        methodsAndConstructors.stream().filter(e -> e.getKind() == ElementKind.CONSTRUCTOR && e.getModifiers().contains(Modifier.PUBLIC)).map(e -> e.toString() +
+                                ": '" + ((ExecutableElement) e).getParameters().stream().map(param -> param.asType() + " " + param.getSimpleName().toString()).collect(java.util.stream.Collectors.joining(", ")) + "'"
+                        ).collect(java.util.stream.Collectors.joining(", ")));
+            }
+        }
+        return false;
+    }
+}

Person.java

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+public class Person {
+    public Person(long personNo, java.util.Date birthDate, String firstName, String lastName) {}
+}

PersonDao.java

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+import javax.annotation.processing.SupportedSourceVersion;
+import javax.lang.model.SourceVersion;
+@SupportedSourceVersion(SourceVersion.RELEASE_0)
+public interface PersonDao {
+    Person getPerson();
+}

readme.md

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+JDK-8184051 : jdk8 -parameters breaks annotation processor parameter names
+----------------------------------------------------------------------
+
+This is the test case showing the broken javac behavior reported in [JDK-8184051](http://bugs.java.com/bugdatabase/view_bug.do?bug_id=JDK-8184051)
+
+    $ ./show_bug.sh
+    javac 1.8.0_131
+    these are the correct argument names, compiled with and without -parameters argument, compiling both classes in a single invocation:
+    warning: Person(long,java.util.Date,java.lang.String,java.lang.String): 'long personNo, java.util.Date birthDate, java.lang.String firstName, java.lang.String lastName'
+    warning: Person(long,java.util.Date,java.lang.String,java.lang.String): 'long personNo, java.util.Date birthDate, java.lang.String firstName, java.lang.String lastName'
+
+    this shows expected missing parameter names when compiled in 2 steps, like in the case of libraries or multiple module projects, without -parameters:
+    warning: Person(long,java.util.Date,java.lang.String,java.lang.String): 'long arg0, java.util.Date arg1, java.lang.String arg2, java.lang.String arg3'
+
+    and finally the bug, same two step compilation as above, but -parameters passed into first step, shows shifted/incorrect parameter names:
+    warning: Person(long,java.util.Date,java.lang.String,java.lang.String): 'long personNo, java.util.Date firstName, java.lang.String lastName, java.lang.String arg3'
+
+This was discovered by Travis Burtrum on June 19th, 2017, when writing test cases for [JdbcMapper](https://code.moparisthebest.com/moparisthebest/JdbcMapper/src/68c1c0482e56c1a2a3ea842a6a71fea3e4444738/jdbcmapper/src/main/java/com/moparisthebest/jdbc/codegen/CompileTimeRowToObjectMapper.java#L88)
+
+it looks like the bug currently doesn't affect javac 9b177:
+
+    javac 9
+    these are the correct argument names, compiled with and without -parameters argument, compiling both classes in a single invocation:
+    warning: Person(long,java.util.Date,java.lang.String,java.lang.String): 'long personNo, java.util.Date birthDate, java.lang.String firstName, java.lang.String lastName'
+    warning: Person(long,java.util.Date,java.lang.String,java.lang.String): 'long personNo, java.util.Date birthDate, java.lang.String firstName, java.lang.String lastName'
+    
+    this shows expected missing parameter names when compiled in 2 steps, like in the case of libraries or multiple module projects, without -parameters:
+    warning: Person(long,java.util.Date,java.lang.String,java.lang.String): 'long arg0, java.util.Date arg1, java.lang.String arg2, java.lang.String arg3'
+    
+    and finally the bug, same two step compilation as above, but -parameters passed into first step, shows shifted/incorrect parameter names:
+    warning: Person(long,java.util.Date,java.lang.String,java.lang.String): 'long personNo, java.util.Date birthDate, java.lang.String firstName, java.lang.String lastName'

show_bug.sh

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+#!/bin/sh
+# delete all classes
+rm -f *.class
+
+javac -version 2>&1
+
+# compile our annotation processor once
+javac ParameterPrintingProcessor.java
+
+echo 'these are the correct argument names, compiled with and without -parameters argument, compiling both classes in a single invocation:'
+javac -parameters -processor ParameterPrintingProcessor Person.java PersonDao.java 2>&1 | head -n1
+rm Person.class PersonDao.class
+javac -processor ParameterPrintingProcessor Person.java PersonDao.java 2>&1 | head -n1
+
+echo
+echo 'this shows expected missing parameter names when compiled in 2 steps, like in the case of libraries or multiple module projects, without -parameters:'
+rm Person.class PersonDao.class
+javac Person.java
+javac -processor ParameterPrintingProcessor PersonDao.java 2>&1 | head -n1
+
+echo
+echo 'and finally the bug, same two step compilation as above, but -parameters passed into first step, shows shifted/incorrect parameter names:'
+rm Person.class PersonDao.class
+javac -parameters Person.java
+# below is the actual invocation of javac where the bug lives, somehow reads saved parameter names from step above incorrectly
+# they are saved correctly above, because you can read them at runtime correctly
+javac -processor ParameterPrintingProcessor PersonDao.java 2>&1 | head -n1
+
+# clean up by deleting all classes
+rm -f *.class