Re: make the shared library optional

[Vicente Olivert Riera <Vincent dot Riera at imgtec dot com>]

Dear Mark Wielaard,

On 11/07/2014 02:16 PM, Mark Wielaard wrote:
> On Mon, 2014-11-03 at 14:45 +0000, Vicente Olivert Riera wrote:
>> I'm having a failure when doing a static build of elfutils because it
>> tries to build a shared library (.so). Could it be possible to add a
>> configure option to disable the shared library so only the static one
>> (.a) would be built?
>>
>> This is the failure I'm talking about:
>>
>> /home/chroot/media/code/buildroot/autobuilder/instance-0/output/host/opt/ext-toolchain/bin/../lib/gcc/mipsel-buildroot-linux-uclibc/4.8.3/../../../../mipsel-buildroot-linux-uclibc/bin/ld:
>> /home/chroot/media/code/buildroot/autobuilder/instance-0/output/host/opt/ext-toolchain/bin/../lib/gcc/mipsel-buildroot-linux-uclibc/4.8.3/crtbeginT.o:
>> relocation R_MIPS_HI16 against `a local symbol' can not be used when
>> making a shared object; recompile with -fPIC
>> /home/chroot/media/code/buildroot/autobuilder/instance-0/output/host/opt/ext-toolchain/bin/../lib/gcc/mipsel-buildroot-linux-uclibc/4.8.3/crtbeginT.o:
>> could not read symbols: Bad value
>> collect2: error: ld returned 1 exit status
>> Makefile:939: recipe for target 'libelf.so' failed
>> make[3]: *** [libelf.so] Error 1


thanks a lot for your reply.


> Does that failure also happen with a normal (not patched) build?

Those patches are necessary. Otherwise it will fail at many points. You
can see the comments on the patches:

http://git.buildroot.net/buildroot/tree/package/elfutils

> It looks like the issue is with the crtbeginT.o code, not with any of
> the elfutils objects? I don't immediately know why that particular
> object is linked into the shared library. Does the toolchain pick up the
> correct version?

I'm sorry, the correct version of what? Also, that's an external
toolchain and I don't have much information about it :S

>> The full build log is here:
>>
>> http://autobuild.buildroot.net/results/16f/16f6956d5a215fe678a45cc4b24ba196309ee05c/build-end.log
> 
> It looks like that is a fairly old 0.155 build with several patches
> applied. Have you tried latest elfutils 0.160 or current git?

I have tried elfutils-0.160, but I'm having this error:

/br/output/host/usr/bin/mipsel-linux-gcc -D_GNU_SOURCE -DHAVE_CONFIG_H
-DLOCALEDIR='"/usr/share/locale"' -I. -I..  -I. -I. -I../lib -I..
-I./../libelf -D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -std=gnu99 -Wall
-Wshadow -Werror -Wunused -Wextra -fgnu89-inline -Wformat=2   -fpic
-D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -pipe -Os -g2 -static -c -o
color.o color.c
color.c: In function ‘parse_opt’:
color.c:135:5: error: passing argument 4 of ‘argp_help’ discards ‘const’
qualifier from pointer target type [-Werror]
     program_invocation_short_name);
     ^
In file included from color.c:34:0:
/home/ldap/vriera/work/mips-buildroots/mips32/output/host/usr/mipsel-buildroot-linux-uclibc/sysroot/usr/include/argp.h:469:13:
note: expected ‘char *’ but argument is of type ‘const char *’
 extern void argp_help (__const struct argp *__restrict __argp,
             ^
cc1: all warnings being treated as errors
make[3]: *** [color.o] Error 1

> If you think any of those patches are useful could you submit them so we
> can review them for inclusion upstream?

Please have a look to those patches here. I think some of them can be
useful:

http://git.buildroot.net/buildroot/tree/package/elfutils

Best regards,
-- 
Vicente Olivert Riera
Graduate Software Engineer, MIPS Processor IP
Imagination Technologies Limited
t: +44 (0)113 2429814
www.imgtec.com