[patch] Fix oddity in personality routine

Tue Dec 1 23:29:00 GMT 2009

On Tue, Dec 01, 2009 at 05:24:29PM +0000, Andrew Haley wrote:
> Jack Howarth wrote:
> > On Tue, Dec 01, 2009 at 09:29:36AM +0000, Andrew Haley wrote:
> >> Jack Howarth wrote:
> >>
> >>> (gdb) 
> >>> 54	 (*real_main) (args);
> >>> (gdb) 
> >>>
> >>> Program received signal EXC_BAD_ACCESS, Could not access memory.
> >>> Reason: KERN_PROTECTION_FAILURE at address: 0x0000000103f05db0
> >>> 0x0000000103f05db0 in ?? () at RowSetEvent.java:51
> >>> 51	RowSetEvent.java: No such file or directory.
> >>> 	in RowSetEvent.java
> >>> (gdb) 
> >>>
> >>> A backtrace only shows...
> >>>
> >>> (gdb) bt
> >>> #0 0x0000000103f05db0 in ?? () at RowSetEvent.java:51
> >>> #1 0x00000001000485be in gnu::java::lang::MainThread::call_main (this=0x104875dc0) at ../../../gcc-4.5-20091128/libjava/gnu/java/lang/natMainThread.cc:54
> >>> Previous frame inner to this frame (gdb could not unwind past this frame)
> >>>
> >>> Let me know if you have any suggestions for debugging this further.
> >> Disassemble the first 10 or so instructions at the instruction where the
> >> EXC_BAD_ACCESS occurs. I think this is a libffi bug.
> >>
> >> Andrew.
> > 
> > Andrew,
> > So just to clarify, for the instance of...
> > 
> > -------------------
> > 
> > (gdb) 
> > 0x00000001004168df in _ZN4java4lang7reflect8Modifier8isPublicEJbi (mod=9) at Modifier.java:258
> > 258	 return (mod & PUBLIC) != 0;
> > (gdb) 
> > gnu::java::lang::MainThread::call_main (this=0x104875dc0) at ../../../gcc-4.5-20091128/libjava/gnu/java/lang/natMainThread.cc:46
> > 46	 msg = "`main' must be public";
> > (gdb) 
> > 45	 else if (! ::java::lang::reflect::Modifier::isPublic(meth->accflags))
> > (gdb) 
> > 54	 (*real_main) (args);
> > (gdb) 
> > 
> > Program received signal EXC_BAD_ACCESS, Could not access memory.
> > Reason: KERN_PROTECTION_FAILURE at address: 0x0000000103f05db0
> > 0x0000000103f05db0 in ?? () at RowSetEvent.java:51
> > 51	RowSetEvent.java: No such file or directory.
> > 	in RowSetEvent.java
> > (gdb) 
> > 
> > A backtrace only shows...
> > 
> > (gdb) bt
> > #0 0x0000000103f05db0 in ?? () at RowSetEvent.java:51
> > #1 0x00000001000485be in gnu::java::lang::MainThread::call_main (this=0x104875dc0) at ../../../gcc-4.5-20091128/libjava/gnu/java/lang/natMainThread.cc:54
> > Previous frame inner to this frame (gdb could not unwind past this frame)
> > 
> > -----------------
> > 
> > I want to disassemble from 0x00000001000485be, right?
>> 0x0000000103f05db0, where the fault happens. I think it's a libffi stub,
> and I think its page permissions are not correctly set.
>> But let's see.
>> What I would do is, at
>> > 54	 (*real_main) (args);
>> disassemble the call instruction, it's probably call ($rax) or somesuch.
> look in $rax with
>> p $rax
>> and disassemble from the address that's in there.
>> Andrew.

Andrew,
 I can't disassemble 0x0000000103f05db0...
(gdb) disassemble 0x0000000103f05db0
No function contains specified address.
Disassembling 0x00000001000485be shows...
(gdb) disassemble 0x00000001000485be
Dump of assembler code for function _ZN3gnu4java4lang10MainThread9call_mainEJvv:
0x00000001000484f0 <_ZN3gnu4java4lang10MainThread9call_mainEJvv+0>:	mov %rbx,-0x18(%rsp)
0x00000001000484f5 <_ZN3gnu4java4lang10MainThread9call_mainEJvv+5>:	mov %rdi,%rbx
0x00000001000484f8 <_ZN3gnu4java4lang10MainThread9call_mainEJvv+8>:	lea 0x94f508(%rip),%rdi # 0x100997a07 <dyld_stub_write+10609>
0x00000001000484ff <_ZN3gnu4java4lang10MainThread9call_mainEJvv+15>:	mov %rbp,-0x10(%rsp)
0x0000000100048504 <_ZN3gnu4java4lang10MainThread9call_mainEJvv+20>:	mov %r12,-0x8(%rsp)
0x0000000100048509 <_ZN3gnu4java4lang10MainThread9call_mainEJvv+25>:	mov 0ドルx16,%esi
0x000000010004850e <_ZN3gnu4java4lang10MainThread9call_mainEJvv+30>:	sub 0ドルx18,%rsp
0x0000000100048512 <_ZN3gnu4java4lang10MainThread9call_mainEJvv+34>:	callq 0x100005a50 <_Z17_Jv_makeUtf8ConstPKci>
0x0000000100048517 <_ZN3gnu4java4lang10MainThread9call_mainEJvv+39>:	lea 0x94f500(%rip),%rdi # 0x100997a1e <dyld_stub_write+10632>
0x000000010004851e <_ZN3gnu4java4lang10MainThread9call_mainEJvv+46>:	mov 0ドルx4,%esi
0x0000000100048523 <_ZN3gnu4java4lang10MainThread9call_mainEJvv+51>:	mov %rax,%r12
0x0000000100048526 <_ZN3gnu4java4lang10MainThread9call_mainEJvv+54>:	callq 0x100005a50 <_Z17_Jv_makeUtf8ConstPKci>
0x000000010004852b <_ZN3gnu4java4lang10MainThread9call_mainEJvv+59>:	mov 0x80(%rbx),%rdi
0x0000000100048532 <_ZN3gnu4java4lang10MainThread9call_mainEJvv+66>:	mov 0ドルx3,%esi
0x0000000100048537 <_ZN3gnu4java4lang10MainThread9call_mainEJvv+71>:	mov %rax,%rbp
0x000000010004853a <_ZN3gnu4java4lang10MainThread9call_mainEJvv+74>:	callq 0x100016830 <_ZN10_Jv_Linker14wait_for_stateEPN4java4lang5ClassEi>
0x000000010004853f <_ZN3gnu4java4lang10MainThread9call_mainEJvv+79>:	mov 0x80(%rbx),%rdi
0x0000000100048546 <_ZN3gnu4java4lang10MainThread9call_mainEJvv+86>:	xor %ecx,%ecx
0x0000000100048548 <_ZN3gnu4java4lang10MainThread9call_mainEJvv+88>:	mov %rbp,%rsi
0x000000010004854b <_ZN3gnu4java4lang10MainThread9call_mainEJvv+91>:	mov %r12,%rdx
0x000000010004854e <_ZN3gnu4java4lang10MainThread9call_mainEJvv+94>:	callq 0x100051b10 <_Z24_Jv_LookupDeclaredMethodPN4java4lang5ClassEP13_Jv_Utf8ConstS4_PS2_>
0x0000000100048553 <_ZN3gnu4java4lang10MainThread9call_mainEJvv+99>:	test %rax,%rax
0x0000000100048556 <_ZN3gnu4java4lang10MainThread9call_mainEJvv+102>:	mov %rax,%rbp
0x0000000100048559 <_ZN3gnu4java4lang10MainThread9call_mainEJvv+105>:	je 0x1000485f0 <_ZN3gnu4java4lang10MainThread9call_mainEJvv+256>
0x000000010004855f <_ZN3gnu4java4lang10MainThread9call_mainEJvv+111>:	movzwl 0x10(%rax),%edi
0x0000000100048563 <_ZN3gnu4java4lang10MainThread9call_mainEJvv+115>:	callq 0x1004168b0 <_ZN4java4lang7reflect8Modifier8isStaticEJbi>
0x0000000100048568 <_ZN3gnu4java4lang10MainThread9call_mainEJvv+120>:	test %al,%al
0x000000010004856a <_ZN3gnu4java4lang10MainThread9call_mainEJvv+122>:	lea 0x94f46a(%rip),%rdx # 0x1009979db <dyld_stub_write+10565>
0x0000000100048571 <_ZN3gnu4java4lang10MainThread9call_mainEJvv+129>:	jne 0x1000485a0 <_ZN3gnu4java4lang10MainThread9call_mainEJvv+176>
0x0000000100048573 <_ZN3gnu4java4lang10MainThread9call_mainEJvv+131>:	mov 0x1329a96(%rip),%rax # 0x101372010 <ffi_type_longdouble+48>
0x000000010004857a <_ZN3gnu4java4lang10MainThread9call_mainEJvv+138>:	lea 0x94f4a2(%rip),%rsi # 0x100997a23 <dyld_stub_write+10637>
0x0000000100048581 <_ZN3gnu4java4lang10MainThread9call_mainEJvv+145>:	mov (%rax),%rdi
0x0000000100048584 <_ZN3gnu4java4lang10MainThread9call_mainEJvv+148>:	xor %eax,%eax
0x0000000100048586 <_ZN3gnu4java4lang10MainThread9call_mainEJvv+150>:	callq 0x100994d4e <dyld_stub_fprintf>
0x000000010004858b <_ZN3gnu4java4lang10MainThread9call_mainEJvv+155>:	mov 0ドルx1,%edi
0x0000000100048590 <_ZN3gnu4java4lang10MainThread9call_mainEJvv+160>:	callq 0x100994d1e <dyld_stub_exit>
0x0000000100048595 <_ZN3gnu4java4lang10MainThread9call_mainEJvv+165>:	nopl 0x0(%rax,%rax,1)
0x000000010004859a <_ZN3gnu4java4lang10MainThread9call_mainEJvv+170>:	nopw 0x0(%rax,%rax,1)
0x00000001000485a0 <_ZN3gnu4java4lang10MainThread9call_mainEJvv+176>:	movzwl 0x10(%rbp),%edi
0x00000001000485a4 <_ZN3gnu4java4lang10MainThread9call_mainEJvv+180>:	callq 0x1004168d0 <_ZN4java4lang7reflect8Modifier8isPublicEJbi>
0x00000001000485a9 <_ZN3gnu4java4lang10MainThread9call_mainEJvv+185>:	test %al,%al
0x00000001000485ab <_ZN3gnu4java4lang10MainThread9call_mainEJvv+187>:	lea 0x94f43f(%rip),%rdx # 0x1009979f1 <dyld_stub_write+10587>
0x00000001000485b2 <_ZN3gnu4java4lang10MainThread9call_mainEJvv+194>:	je 0x100048573 <_ZN3gnu4java4lang10MainThread9call_mainEJvv+131>
0x00000001000485b4 <_ZN3gnu4java4lang10MainThread9call_mainEJvv+196>:	mov 0x90(%rbx),%rdi
0x00000001000485bb <_ZN3gnu4java4lang10MainThread9call_mainEJvv+203>:	callq *0x18(%rbp)
0x00000001000485be <_ZN3gnu4java4lang10MainThread9call_mainEJvv+206>:	callq 0x100062450 <_Z14_Jv_ThreadWaitv>
0x00000001000485c3 <_ZN3gnu4java4lang10MainThread9call_mainEJvv+211>:	lea 0x1629dde(%rip),%rax # 0x1016723a8 <_ZN4java4lang11ThreadGroup22had_uncaught_exceptionE>
0x00000001000485ca <_ZN3gnu4java4lang10MainThread9call_mainEJvv+218>:	mov (%rsp),%rbx
0x00000001000485ce <_ZN3gnu4java4lang10MainThread9call_mainEJvv+222>:	mov 0x8(%rsp),%rbp
0x00000001000485d3 <_ZN3gnu4java4lang10MainThread9call_mainEJvv+227>:	mov 0x10(%rsp),%r12
0x00000001000485d8 <_ZN3gnu4java4lang10MainThread9call_mainEJvv+232>:	movzbl (%rax),%edi
0x00000001000485db <_ZN3gnu4java4lang10MainThread9call_mainEJvv+235>:	add 0ドルx18,%rsp
0x00000001000485df <_ZN3gnu4java4lang10MainThread9call_mainEJvv+239>:	jmpq 0x100409600 <_ZN4java4lang7Runtime20exitNoChecksAccessorEJvi>
0x00000001000485e4 <_ZN3gnu4java4lang10MainThread9call_mainEJvv+244>:	nopw 0x0(%rax,%rax,1)
0x00000001000485ea <_ZN3gnu4java4lang10MainThread9call_mainEJvv+250>:	nopw 0x0(%rax,%rax,1)
0x00000001000485f0 <_ZN3gnu4java4lang10MainThread9call_mainEJvv+256>:	lea 0x94f3c1(%rip),%rdx # 0x1009979b8 <dyld_stub_write+10530>
0x00000001000485f7 <_ZN3gnu4java4lang10MainThread9call_mainEJvv+263>:	jmpq 0x100048573 <_ZN3gnu4java4lang10MainThread9call_mainEJvv+131>
Do I need to actually stop the process of stepping through the code before I hit
the crash in order to disassemble real_main? I tried...
(gdb) break ../../../gcc-4.5-20091128/libjava/gnu/java/lang/natMainThread.cc:46
Breakpoint 1 at 0x20c49ba4b0a5ab: file ../../../gcc-4.5-20091128/libjava/gnu/java/lang/natMainThread.cc, line 46.
(gdb) r testme.java -fbootclasspath=/sw/share/java/ecj/ecj.jar:./:/sw/lib/gcc4.5/share/java/libgcj-4.5.0.jar -fsource=1.5 -ftarget=1.5 -fzip-dependency /var/folders/1C/1CdoNxmNFHyOIjNBLNuJh++++TM/-Tmp-//ccQOWl1c.zip -fzip-target /var/folders/1C/1CdoNxmNFHyOIjNBLNuJh++++TM/-Tmp-//cc4p4DHj.jar
Starting program: /sw/lib/gcc4.5/libexec/gcc/x86_64-apple-darwin9.8.0/4.5.0/ecj1 testme.java -fbootclasspath=/sw/share/java/ecj/ecj.jar:./:/sw/lib/gcc4.5/share/java/libgcj-4.5.0.jar -fsource=1.5 -ftarget=1.5 -fzip-dependency /var/folders/1C/1CdoNxmNFHyOIjNBLNuJh++++TM/-Tmp-//ccQOWl1c.zip -fzip-target /var/folders/1C/1CdoNxmNFHyOIjNBLNuJh++++TM/-Tmp-//cc4p4DHj.jar
warning: posix_spawn failed, trying execvp, error: 86
Reading symbols for shared libraries +++++.. done
Breakpoint 1 at 0x1000485ab: file ../../../gcc-4.5-20091128/libjava/gnu/java/lang/natMainThread.cc, line 46.
Breakpoint 1, gnu::java::lang::MainThread::call_main (this=0x104875dc0) at ../../../gcc-4.5-20091128/libjava/gnu/java/lang/natMainThread.cc:46
46	 msg = "`main' must be public";
(gdb) s
Current language: auto; currently c++
45	 else if (! ::java::lang::reflect::Modifier::isPublic(meth->accflags))
(gdb) s
54	 (*real_main) (args);
(gdb) bt 
#0 gnu::java::lang::MainThread::call_main (this=0x104875dc0) at ../../../gcc-4.5-20091128/libjava/gnu/java/lang/natMainThread.cc:54
#1 0x0000000104875dc0 in ?? () at ClassHelper.java:106
#2 0x0000000104875f00 in ?? () at ClassHelper.java:106
#3 0x000000010493e980 in ?? () at ClassHelper.java:106
#4 0x00000001000b1b74 in _ZN3gnu4java4lang10MainThread3runEJvv (this=0x104875dc0) at MainThread.java:106
Previous frame inner to this frame (gdb could not unwind past this frame)
(gdb) info line 54
Line 54 of "../../../gcc-4.5-20091128/libjava/gnu/java/lang/natMainThread.cc" starts at address 0x1000485b4 <_ZN3gnu4java4lang10MainThread9call_mainEJvv+196> and ends at 0x1000485be <_ZN3gnu4java4lang10MainThread9call_mainEJvv+206>.
(gdb) disassemble 0x1000485b4 0x1000485be
Dump of assembler code from 0x1000485b4 to 0x1000485be:
0x00000001000485b4 <_ZN3gnu4java4lang10MainThread9call_mainEJvv+196>:	mov 0x90(%rbx),%rdi
0x00000001000485bb <_ZN3gnu4java4lang10MainThread9call_mainEJvv+203>:	callq *0x18(%rbp)
End of assembler dump.
(gdb) 
I'm not sure what to do at this point to disassemble the call destination...
(gdb) disassemble *0x18(%rbp)
A syntax error in expression, near `%rbp)'.
(gdb) disassemble 0x18(%rbp)
A syntax error in expression, near `%rbp)'.
(gdb) disassemble %rbp 
A syntax error in expression, near `%rbp'.
I am at the correct spot though since the next step causes the crash. Also I do
notice that the output from "disassemble 0x1000485b4 0x1000485be" is listed in
the longer disassembly from 0x00000001000485be.
 Jack