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

[Florian Fainelli]

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?
-- 
Florian