Re: [FYI] Need to do a full rebuild if you are on Linux x86 host

[Paolo Bonzini <pbonzini@redhat.com>]

On 11/22/2011 10:41 AM, Gerd Hoffmann wrote:
> On 11/22/11 01:25, Anthony Liguori wrote:
>> Due to this commit:
>>
>> commit 40d6444e91c6ab17e5e8ab01d4eece90cbc4afed
>> Author: Avi Kivity<avi@redhat.com>
>> Date:   Tue Nov 15 20:12:17 2011 +0200
>>
>>      configure: build position independent executables on x86-Linux hosts
>>
>> PIE binaries cannot be linked with non-PIE binaries and make is not
>> smart enough to rebuild when the CFLAGS have changed.
>
> Breaks build on RHEL-5 and probably also other not-so-recent linux distros.
>
> [ ... ]
>    CC    i386-softmmu/exec.o
> [ ... ]
>    LINK  i386-softmmu/qemu-system-i386
> /usr/bin/ld: exec.o: relocation R_X86_64_TPOFF32 against
> `tls__cpu_single_env' can not be used when making a shared object;
> recompile with -fPIC
> exec.o: could not read symbols: Bad value
> collect2: ld returned 1 exit status
> make[1]: *** [qemu-system-i386] Error 1
> make: *** [subdir-i386-softmmu] Error 2

It can be worked around by replacing "-fpie" with "-fpic" or (to avoid a 
rather bad performance degradation) "-fpic -ftls-model=initial-exec" but 
it's a bug in the linker and it should be fixed in RHEL:

http://sourceware.org/bugzilla/show_bug.cgi?id=10434 (upstream BZ)
https://bugzilla.redhat.com/show_bug.cgi?id=755872 (RHEL BZ)

Paolo