Re: [PATCH v2] um: Avoid longjmp/setjmp symbol clashes with libpthread.a

From: Florian Fainelli
Date: Thu Jun 01 2017 - 15:38:11 EST


On 05/24/2017 09:19 AM, Florian Fainelli wrote:
> On 05/24/2017 12:02 AM, Richard Weinberger wrote:
>> Florian,
>>
>> Am 24.05.2017 um 02:32 schrieb Florian Fainelli:
>>> Building a statically linked UML kernel on a Centos 6.9 host resulted in
>>> the following linking failure (GCC 4.4, glibc-2.12):
>>>
>>> /usr/lib/gcc/x86_64-redhat-linux/4.4.7/../../../../lib64/libpthread.a(libpthread.o):
>>> In function `siglongjmp':
>>> (.text+0x8490): multiple definition of `longjmp'
>>> arch/x86/um/built-in.o:/local/users/fainelli/openwrt/trunk/build_dir/target-x86_64_musl/linux-uml/linux-4.4.69/arch/x86/um/setjmp_64.S:44:
>>> first defined here
>>> /usr/lib/gcc/x86_64-redhat-linux/4.4.7/../../../../lib64/libpthread.a(libpthread.o):
>>> In function `sem_open':
>>> (.text+0x77cd): warning: the use of `mktemp' is dangerous, better use
>>> `mkstemp'
>>> collect2: ld returned 1 exit status
>>> make[4]: *** [vmlinux] Error 1
>>>
>>> Adopt a solution similar to the one done for vmap where we define
>>> longjmp/setjmp to be kernel_longjmp/setjmp. In the process, make sure we
>>> do rename the functions in arch/x86/um/setjmp_*.S accordingly.
>>
>> What is not so clear to me, why are you facing this build issue and other users, including me,
>> not?
>
> Presumably because we are not using the same glibc version? The one I
> have installed on this machine is glibc-2.12, do you want me to attach a
> copy of it?

Richard, what do we do with this?
--
Florian