recent java segvs, in exception code

[Tom Tromey <tromey at redhat dot com>]

Today I updated the gcc 3.0 branch and did a complete rebuild from
scratch.  I'm using x86 Red Hat Linux 6.2.

Certain programs crash like this:

#0  0x4050455a in next_stack_level (pc=0x40165839, udata=0xbf7ffa7c, 
    caller_udata=0xbf7ff9fc, saved_regs=0xbf7ff92c)
   from /x1/gcc3/build/gcc/libgcc_s.so.0
#1  0x405046aa in throw_helper (eh=0x80c86a0, pc=0x40165839, 
    my_udata=0xbf7ffb3c, offset_p=0xbf7ffb38)
   from /x1/gcc3/build/gcc/libgcc_s.so.0
#2  0x40504a0a in __throw () from /x1/gcc3/build/gcc/libgcc_s.so.0
#3  0x4016583a in _Jv_Throw (value=0x8062e40)
    at ../../../gcc/libjava/exception.cc:160
#4  0x4019058b in java.lang.StringBuffer.insert(int, java.lang.String) (
    this=0x809dc48, offset=-2, str=0x809ddc8)
    at ../../../gcc/libjava/java/lang/StringBuffer.java:432
#5  0x080493b7 in StringBuffer_1.main(java.lang.String[]) ()
    at StringBuffer_1.java:54
#6  0x401727db in gnu::gcj::runtime::FirstThread::run() (this=0x8065f00)
    at ../../../gcc/libjava/gnu/gcj/runtime/natFirstThread.cc:146
#7  0x4017daeb in java::lang::Thread::run_(java::lang::Object*) (obj=0x8065f00)
    at ../../../gcc/libjava/java/lang/natThread.cc:276
#8  0x40292025 in really_start(void*) (x=0x80caff8)
    at ../../../gcc/libjava/posix-threads.cc:349
#9  0x4051964c in GC_start_routine (arg=0x807efc0)
    at ../../../gcc/boehm-gc/linux_threads.c:633
#10 0x40531b85 in pthread_start_thread (arg=0xbf7ffe40) at manager.c:241
#11 0x4053254c in pthread_start_thread_event (arg=0xbf7ffe40) at manager.c:264


The problem seems to be here:

(gdb) p caller_udata->base_offset
$7 = 135038872
(gdb) p caller_udata->cfa + caller_udata->base_offset
$8 = (void *) 0xc78c837c
(gdb) p *(int*) $
Cannot access memory at address 0xc78c837c


This problem only seems to happen when I run `make
check-target-libjava'.  If I copy the failing program (in this case,
StringBuffer_1.java) elsewhere and compile it with the installed
gcj, then it works.

Tom