Lots has changed since we forked Android's libcore, so merging the
latest upstream code has required extensive changes to the
Avian/Android port.
One big change is that we now use Avian's versions of
java.lang.Object, java.lang.Class, java.lang.ClassLoader, some
java.lang.reflect.* classes, etc. instead of the Android versions.
The main reason is that the Android versions have become very
Dex/Dalvik-specific, and since Avian is based on Java class files, not
dex archives, that code doesn't make sense here. This has the side
benefit that we can share more native code with classpath-avian.cpp
and reduce the amount of Java/C++ code duplication.
So there I was, planning to just fix one little bug: Thread.holdsLock
and Thread.yield were missing for the Android class library. Easy
enough, right? So, I added a test, got it passing, and figured I'd go
ahead and run ci.sh with all three class libraries. Big mistake.
Here's the stuff I found:
* minor inconsistency in README.md about OpenSSL version
* untested, broken Class.getEnclosingMethod (reported by Josh)
* JNI test failed for tails=true Android build
* Runtime.nativeExit missing for Android build
* obsolete assertion in CallEvent broke tails=true Android build
* obsolete superclass field offset padding broke bootimage=true Android build
* runtime annotation parsing broke bootimage=true Android build
(because we couldn't modify Addendum.annotationTable for classes in
the heap image)
* ci.sh tried building with both android=... and openjdk=..., which
the makefile rightfully balked at
Sorry this is all in a single commit; I didn't expect so many
unrelated issues, and I'm too lazy to break them apart.
617bd85 broke the Android build by creating an unresolvable
order-of-operations bug in classpath-android.cpp's
MyClasspath::preBoot method.
The problem is that, while JNIEnv::FindClass is supposed to initialize
the class that it finds, this causes JniConstants::init to indirectly
invoke native methods which are not registered until JNI_OnLoad is
called (which happens after JniConstants::init is called). However,
if we call JNI_OnLoad first, that causes methods to be invoked which
rely on JniConstants::init having already been run.
I haven't checked to see how Dalvik handles this, but I don't see any
way around the problem besides disabling initialization by
JNIEnv::FindClass until the preBoot phase is complete. Moreover, it's
dangerous to allow Java code to be invoked so early anyway, since the
VM is not yet fully initialized.
There's more work to do to derive all the properties of a given class
from its code source (e.g. JAR file), but this at least ensures that
ClassLoader.getPackage will actually return something non-null when
appropriate.
An inner class has two sets of modifier flags: one is declared in the
usual place in the class file and the other is part of the
InnerClasses attribute. Not only is that redundant, but they can
contradict, and the VM can't just pick one and roll with it. Instead,
Class.getModifiers must return the InnerClasses version, whereas
reflection must check the top-level version. So even if
Class.getModifiers says the class is protected, it might still be
public for the purpose of reflection depending on what the
InnerClasses attribute says. Crazy? Yes.
Android's class library uses this to find out whether the VM supports
compareAndSwapLong natively. Avian does on all platforms, so we just
return true.
