libgcj/7709: NullPointerException in _Jv_ResolvePoolEntry

[jmr@ugcs.caltech.edu]

>Number:         7709
>Category:       libgcj
>Synopsis:       NullPointerException in _Jv_ResolvePoolEntry
>Confidential:   no
>Severity:       non-critical
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Sat Aug 24 00:26:02 PDT 2002
>Closed-Date:
>Last-Modified:
>Originator:     Jesse Rosenstock
>Release:        3.3 20020820 (experimental)
>Organization:
>Environment:
System: Linux churchill 2.4.3-12 #1 Fri Jun 8 15:05:56 EDT 2001 i686 unknown
Architecture: i686

	
host: i686-pc-linux-gnu
build: i686-pc-linux-gnu
target: i686-pc-linux-gnu
configured with: ../gcc/configure --prefix=/home/user/jmr/app/gcc --enable-langs=c++,java --enable-shared --enable-threads=posix --with-as=/home/user/jmr/app/binutils/bin/as --with-ld=/home/user/jmr/app/binutils/bin/ld
>Description:
	In _Jv_ResolvePoolEntry, if no method is found in the 
	JV_CONSTANT_Methodref/JV_CONSTANT_InterfaceMethodref case,
	_Jv_DetermineVTableIndex may be called with found_class == NULL,
	causing a NullPointerException when _Jv_DetermineVTableIndex
	calls getSuperclass().
>How-To-Repeat:
	I haven't reduced it to a small test case yet, but it is clear
	that some error other than NullPointerException should be reported.
>Fix:
I'm not sure about this, but it does get rid of the NullPointerException,
and since the_method is not modified by the code I moved, perhaps the
author intended the the_method == 0 check to go first.

Index: resolve.cc
===================================================================
RCS file: /cvsroot/gcc/gcc/libjava/resolve.cc,v
retrieving revision 1.29
diff -c -r1.29 resolve.cc
*** resolve.cc  20 Jun 2002 15:10:49 -0000      1.29
--- resolve.cc  24 Aug 2002 06:07:08 -0000
***************
*** 300,315 ****
        // with either loader should produce the same result,
        // i.e., exactly the same jclass object. JVMS 5.4.3.3    
      
-       if (pool->tags[index] == JV_CONSTANT_InterfaceMethodref)
-       vtable_index = -1;
-       else
-       vtable_index = _Jv_DetermineVTableIndex
-         (found_class, method_name, method_signature);
- 
-       if (vtable_index == METHOD_NOT_THERE)
-       throw_incompatible_class_change_error
-         (JvNewStringLatin1 ("method not found"));
- 
        if (the_method == 0)
        {
          jstring msg = JvNewStringLatin1 ("method ");
--- 300,305 ----
***************
*** 320,325 ****
--- 310,325 ----
          throw new java::lang::NoSuchMethodError (msg);
        }
        
+       if (pool->tags[index] == JV_CONSTANT_InterfaceMethodref)
+       vtable_index = -1;
+       else
+       vtable_index = _Jv_DetermineVTableIndex
+         (found_class, method_name, method_signature);
+ 
+       if (vtable_index == METHOD_NOT_THERE)
+       throw_incompatible_class_change_error
+         (JvNewStringLatin1 ("method not found"));
+ 
        pool->data[index].rmethod = 
        _Jv_BuildResolvedMethod(the_method,
                                found_class,
>Release-Note:
>Audit-Trail:
>Unformatted: