Re: [PATCH] gdb/elfread.c: Enable ifunc support on ARM.

[Will Newton <will.newton@linaro.org>]

On 23 January 2014 15:21, Will Newton <will.newton@linaro.org> wrote:
> On 16 December 2013 18:24, Will Newton <will.newton@linaro.org> wrote:
>>
>> There are two failures in the gnu-ifunc.exp test on ARM. These are
>> due to the failure to resolve the correct target function when
>> attempting to breakpoint a GNU ifunc resolved function:
>>
>> (gdb) break gnu_ifunc
>> Breakpoint 4 at gnu-indirect-function resolver at 0x2aacb5a2
>>
>> when gnu_ifunc has been resolved this should actually be:
>>
>> (gdb) break gnu_ifunc
>> Breakpoint 4 at 0x868c
>>
>> There are two reasons for this. The first is that ARM does not have a
>> separate .got.plt section so looking this up will always fail. The second
>> is that the Thumb bit needs to be stripped from the address to allow
>> it to be reliably compared when inserting into the ifunc cache.
>>
>> Tested with no regressions on arm-linux-gnueabihf and
>> x86_64-unknown-linux-gnu.
>>
>> gdb/ChangeLog:
>>
>> 2013-12-16  Will Newton  <will.newton@linaro.org>
>>
>>         * elfread.c (elf_rel_plt_read): Look for a .got section if
>>         looking up .got.plt fails.
>>         (elf_gnu_ifunc_resolve_by_got): Call gdbarch_addr_bits_remove
>>         on address passed to elf_gnu_ifunc_record_cache.
>>         (elf_gnu_ifunc_resolve_addr): Likewise.
>>         (elf_gnu_ifunc_resolver_return_stop): Likewise.
>> ---
>>  gdb/elfread.c | 10 +++++++++-
>>  1 file changed, 9 insertions(+), 1 deletion(-)
>
> Ping?

Ping?

Despite the subject the contents of this patch are not ARM specific
and change generic functionality.

-- 
Will Newton
Toolchain Working Group, Linaro