re PR java/18278 (JNI functions cannot return a weak reference)

gcc/java:
	PR java/18278:
	* expr.c (build_jni_stub): Unwrap the return value.
	* java-tree.h (soft_unwrapjni_node): New define.
	(enum java_tree_index): Added JTI_SOFT_UNWRAPJNI_NODE.
	* decl.c (java_init_decl_processing): Initialize
	soft_unwrapjni_node.
libjava:
	PR java/18278:
	* testsuite/libjava.jni/pr18278.out: New file.
	* testsuite/libjava.jni/pr18278.c: New file.
	* testsuite/libjava.jni/pr18278.java: New file.
	* include/jvm.h (_Jv_UnwrapJNIweakReference): Declare.
	* jni.cc (_Jv_UnwrapJNIweakReference): New function.
	(call): Unwrap return value if needed.

From-SVN: r107676

6 files changed, 50 insertions, 0 deletions

diff --git a/libjava/ChangeLog b/libjava/ChangeLog
index d303755..2d88d05 100644
--- a/libjava/ChangeLog
+++ b/libjava/ChangeLog
@@ -1,3 +1,13 @@
+2005-11-28  Tom Tromey  <tromey@redhat.com>
+
+	PR java/18278:
+	* testsuite/libjava.jni/pr18278.out: New file.
+	* testsuite/libjava.jni/pr18278.c: New file.
+	* testsuite/libjava.jni/pr18278.java: New file.
+	* include/jvm.h (_Jv_UnwrapJNIweakReference): Declare.
+	* jni.cc (_Jv_UnwrapJNIweakReference): New function.
+	(call): Unwrap return value if needed.
+
 2005-11-25  Mark Wielaard  <mark@klomp.org>
 
 	* standard.omit.in: Remove javax/rmi, org/omg, gnu/CORBA and
diff --git a/libjava/include/jvm.h b/libjava/include/jvm.h
index fc104d6..8d34059 100644
--- a/libjava/include/jvm.h
+++ b/libjava/include/jvm.h
@@ -459,6 +459,8 @@ extern "C" void _Jv_RegisterClasses_Counted (const jclass *classes,
 extern "C" void _Jv_RegisterResource (void *vptr);
 extern void _Jv_UnregisterClass (_Jv_Utf8Const*, java::lang::ClassLoader*);
 
+extern "C" jobject _Jv_UnwrapJNIweakReference (jobject);
+
 extern jclass _Jv_FindClass (_Jv_Utf8Const *name,
 			     java::lang::ClassLoader *loader);
 extern jclass _Jv_FindClassFromSignature (char *,
diff --git a/libjava/jni.cc b/libjava/jni.cc
index 13bb12c..fd82706 100644
--- a/libjava/jni.cc
+++ b/libjava/jni.cc
@@ -226,6 +226,12 @@ unwrap (T *obj)
   return reinterpret_cast<T *> (wr->get ());
 }
 
+jobject
+_Jv_UnwrapJNIweakReference (jobject obj)
+{
+  return unwrap (obj);
+}
+
 
 
 static jobject JNICALL
@@ -2304,6 +2310,13 @@ _Jv_JNIMethod::call (ffi_cif *, void *ret, ffi_raw *args, void *__this)
 		     ret, real_args);
 #endif
 
+  // We might need to unwrap a JNI weak reference here.
+  if (_this->jni_cif.rtype == &ffi_type_pointer)
+    {
+      _Jv_value *val = (_Jv_value *) ret;
+      val->object_value = unwrap (val->object_value);
+    }
+
   if (sync != NULL)
     _Jv_MonitorExit (sync);
 
diff --git a/libjava/testsuite/libjava.jni/pr18278.c b/libjava/testsuite/libjava.jni/pr18278.c
new file mode 100644
index 0000000..7ca73a4
--- /dev/null
+++ b/libjava/testsuite/libjava.jni/pr18278.c
@@ -0,0 +1,10 @@
+#include <jni.h>
+#include <stdio.h>
+
+#include "pr18278.h"
+
+jobject Java_pr18278_weakRef(JNIEnv *env, jclass cls, jobject data)
+{
+  jobject r =  (* env)->NewWeakGlobalRef(env, data);
+  return r;
+}
diff --git a/libjava/testsuite/libjava.jni/pr18278.java b/libjava/testsuite/libjava.jni/pr18278.java
new file mode 100644
index 0000000..8a39dde
--- /dev/null
+++ b/libjava/testsuite/libjava.jni/pr18278.java
@@ -0,0 +1,13 @@
+public class pr18278 {
+    public pr18278() {}
+
+    public static void main(String[] args) {
+        System.loadLibrary("pr18278");
+	String bob = "Bob";
+	Object o = weakRef("Bob");
+	System.out.println(o);
+	System.out.println(bob == o);
+    }
+
+    static native Object weakRef(Object o);
+}
diff --git a/libjava/testsuite/libjava.jni/pr18278.out b/libjava/testsuite/libjava.jni/pr18278.out
new file mode 100644
index 0000000..e01142a
--- /dev/null
+++ b/libjava/testsuite/libjava.jni/pr18278.out
@@ -0,0 +1,2 @@
+Bob
+true