Comment 7 for bug 1157109

I have reproduced the issue with the binary you have attached.

Thanks!

On 20 September 2013 15:00, Omair Javaid <email address hidden> wrote:
> I recompiled the code with no changes on a pandaboard. (Linux
> 3.5.0-213-omap4 #20-Ubuntu SMP PREEMPT)
>
> GCC version: 4.7.2
>
> Let me recheck this with your binaries.
>
> thanks!
>
> On 20 September 2013 14:47, Christophe Lyon <email address hidden> wrote:
>> Did you re-compile the C source I attached or did you use the binary I
>> supplied?
>>
>> Your disassembly does not match the contents of test1.thumb I supplied.
>>
>> --
>> You received this bug notification because you are a bug assignee.
>> https://bugs.launchpad.net/bugs/1157109
>>
>> Title:
>> record mode confuses disassembler
>>
>> Status in GNU Debugger:
>> New
>> Status in Linaro GDB:
>> Incomplete
>>
>> Bug description:
>> As of current GDB trunk (2013-03-18), using record mode can confuse
>> the disassembler.
>>
>> I attach test1.c and test1.thumb (compiled in the default thumb mode
>> with gcc -g -o test1.thumb test1.c).
>>
>> $ gdb test1.thumb
>> GNU gdb (GDB) 7.6.50.20130317-cvs
>> [...]
>> (gdb) b main
>> Breakpoint 1 at 0x8396: file test1.c, line 5.
>> (gdb) b test1.c:8
>> Breakpoint 2 at 0x83b0: file test1.c, line 8.
>> (gdb) r
>> Starting program: /home/lyon/test1.thumb
>>
>> Breakpoint 1, main () at test1.c:5
>> 5 int i=0;
>> (gdb) target record-full
>> (gdb) disassemble main
>> Dump of assembler code for function main:
>> 0x00008390 <+0>: push {r7, lr}
>> 0x00008392 <+2>: sub sp, #8
>> 0x00008394 <+4>: add r7, sp, #0
>> => 0x00008396 <+6>: mov.w r3, #0
>> 0x0000839a <+10>: str r3, [r7, #4]
>> 0x0000839c <+12>: movw r0, #33808 ; 0x8410
>> 0x000083a0 <+16>: movt r0, #0
>> 0x000083a4 <+20>: blx 0x82e4 <puts>
>> 0x000083a8 <+24>: ldr r3, [r7, #4]
>> 0x000083aa <+26>: add.w r3, r3, #1
>> 0x000083ae <+30>: str r3, [r7, #4]
>> 0x000083b0 <+32>: mov r0, r3
>> 0x000083b2 <+34>: add.w r7, r7, #8
>> 0x000083b6 <+38>: mov sp, r7
>> 0x000083b8 <+40>: pop {r7, pc}
>> End of assembler dump.
>> (gdb) c
>> Continuing.
>> Process record doesnt support thumb32 instruction 0x300f04f at address 0x8396.
>> main () at test1.c:5
>> 5 int i=0;
>> Process record: failed to record execution log.
>> (gdb) disassemble main
>> Dump of assembler code for function main:
>> 0x00008390 <+0>: push {r7, lr}
>> 0x00008392 <+2>: sub sp, #8
>> 0x00008394 <+4>: add r7, sp, #0
>> => 0x00008396 <+6>: mov.w r3, #0
>> 0x0000839a <+10>: ; <UNDEFINED> instruction: 0xde01
>> 0x0000839c <+12>: movw r0, #33808 ; 0x8410
>> 0x000083a0 <+16>: movt r0, #0
>> 0x000083a4 <+20>: blx 0x82e4 <puts>
>> 0x000083a8 <+24>: ldr r3, [r7, #4]
>> 0x000083aa <+26>: add.w r3, r3, #1
>> 0x000083ae <+30>: str r3, [r7, #4]
>> 0x000083b0 <+32>: mov r0, r3
>> 0x000083b2 <+34>: add.w r7, r7, #8
>> 0x000083b6 <+38>: mov sp, r7
>> 0x000083b8 <+40>: pop {r7, pc}
>> End of assembler dump.
>>
>>
>> Notice how instruction at 0x8396 became UNDEFINED.
>>
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