lttng-tools: Fix compilation

Compiling lttng-tools fails when lttng-libust is enabled bacause of a missing
-lurcu-bp in the linker command line, at least for linaro 2012.12 toolchain.

Signed-off-by: Stephan Hoffmann <sho@relinux.de>
---
 package/lttng-tools/lttng-tools.mk |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)

Hi Stephan,

2013/2/4 Stephan Hoffmann <sho@relinux.de>:
> Compiling lttng-tools fails when lttng-libust is enabled bacause of a missing
s/bacause/because/

> -lurcu-bp in the linker command line, at least for linaro 2012.12 toolchain.
hum... weird!

lttng-tools handles that in its configure file, checking for
ustctl_set_filter availability in liblttng-ust-ctl; see:
http://git.lttng.org/?p=lttng-tools.git;a=blob;f=configure.ac;h=91e76f06a98700d2a9deb36c29a650176e62c4ab;hb=HEAD#l137

Are you sure lttng-libust was correctly built before?
Could you give more details about the linking error?

It may also be something to report upstream, lttng guys are quite responsive.

>
> Signed-off-by: Stephan Hoffmann <sho@relinux.de>
> ---
>  package/lttng-tools/lttng-tools.mk |    2 ++
>  1 files changed, 2 insertions(+), 0 deletions(-)
>
> diff --git a/package/lttng-tools/lttng-tools.mk b/package/lttng-tools/lttng-tools.mk
> index 5be3abb..288e351 100644
> --- a/package/lttng-tools/lttng-tools.mk
> +++ b/package/lttng-tools/lttng-tools.mk
> @@ -21,6 +21,8 @@ LTTNG_AUTORECONF = YES
>  ifeq ($(BR2_PACKAGE_LTTNG_LIBUST),y)
>  LTTNG_TOOLS_CONF_OPT += --enable-lttng-ust
>  LTTNG_TOOLS_DEPENDENCIES += lttng-libust
> +# Build fails without this, at least with Linuaro 2012.12 toolchain
> +LTTNG_TOOLS_CONF_ENV += LDFLAGS="$(TARGET_LDFLAGS) -lurcu-bp"
>  else
>  LTTNG_TOOLS_CONF_OPT += --disable-lttng-ust
>  endif
> --
> 1.7.0.4
>
> _______________________________________________
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> buildroot@busybox.net
> http://lists.busybox.net/mailman/listinfo/buildroot


Regards,

Hello Samuel,


Am 04.02.2013 15:49, schrieb Samuel Martin:
> Hi Stephan,
>
> 2013/2/4 Stephan Hoffmann <sho@relinux.de>:
>> Compiling lttng-tools fails when lttng-libust is enabled bacause of a missing
> s/bacause/because/
>
>> -lurcu-bp in the linker command line, at least for linaro 2012.12 toolchain.
> hum... weird!
>
> lttng-tools handles that in its configure file, checking for
> ustctl_set_filter availability in liblttng-ust-ctl; see:
> http://git.lttng.org/?p=lttng-tools.git;a=blob;f=configure.ac;h=91e76f06a98700d2a9deb36c29a650176e62c4ab;hb=HEAD#l137
>
> Are you sure lttng-libust was correctly built before?
> Could you give more details about the linking error?
the error message I always got is:
> make[4]: Betrete Verzeichnis
> '/opt/scratch/buildroot/output/build/lttng-tools-2.1.1/tests/tools/streaming'
>   CCLD   gen-ust-events
> /opt/scratch/buildroot/output/host/opt/ext-toolchain/bin/../lib/gcc/arm-linux-gnueabihf/4.7.3/../../../../arm-linux-gnueabihf/bin/ld:
> tp.o: undefined reference to symbol 'rcu_dereference_sym'
> /opt/scratch/buildroot/output/host/opt/ext-toolchain/bin/../lib/gcc/arm-linux-gnueabihf/4.7.3/../../../../arm-linux-gnueabihf/bin/ld:
> note: 'rcu_dereference_sym' is defined in DSO
> /opt/scratch/buildroot/output/host/usr/arm-buildroot-linux-gnueabi/sysroot/usr/lib/liburcu-bp.so.1
> so try adding it to the linker command line
> /opt/scratch/buildroot/output/host/usr/arm-buildroot-linux-gnueabi/sysroot/usr/lib/liburcu-bp.so.1:
> could not read symbols: Invalid operation
> collect2: error: ld returned 1 exit status
> make[4]: *** [gen-ust-events] Fehler 1
> make[4]: Verlasse Verzeichnis
> '/opt/scratch/buildroot/output/build/lttng-tools-2.1.1/tests/tools/streaming'
But even worse: now I cannot reproduce it. Maybe you're right and there
was something wrong with libust. I cannot verify that I really called
"make clean" while hunting for this. So for now let's assume that I
forgot it.

Btw: Originally, I wanted to use the internal toolchain, but the default
one (4.6) cannot compile libust (see autobuild logs). After switching to
gcc 4.7 it compiles, but "lttng list -k" does not find any events.

Kind regards

Stephan
>
> It may also be something to report upstream, lttng guys are quite responsive.
>
>> Signed-off-by: Stephan Hoffmann <sho@relinux.de>
>> ---
>>  package/lttng-tools/lttng-tools.mk |    2 ++
>>  1 files changed, 2 insertions(+), 0 deletions(-)
>>
>> diff --git a/package/lttng-tools/lttng-tools.mk b/package/lttng-tools/lttng-tools.mk
>> index 5be3abb..288e351 100644
>> --- a/package/lttng-tools/lttng-tools.mk
>> +++ b/package/lttng-tools/lttng-tools.mk
>> @@ -21,6 +21,8 @@ LTTNG_AUTORECONF = YES
>>  ifeq ($(BR2_PACKAGE_LTTNG_LIBUST),y)
>>  LTTNG_TOOLS_CONF_OPT += --enable-lttng-ust
>>  LTTNG_TOOLS_DEPENDENCIES += lttng-libust
>> +# Build fails without this, at least with Linuaro 2012.12 toolchain
>> +LTTNG_TOOLS_CONF_ENV += LDFLAGS="$(TARGET_LDFLAGS) -lurcu-bp"
>>  else
>>  LTTNG_TOOLS_CONF_OPT += --disable-lttng-ust
>>  endif
>> --
>> 1.7.0.4
>>
>> _______________________________________________
>> buildroot mailing list
>> buildroot@busybox.net
>> http://lists.busybox.net/mailman/listinfo/buildroot
>
> Regards,
>