[dizzy][PATCH] libunwind: backport patch to link against libgcc_s intead of libgcc

[dizzy][PATCH] libunwind: backport patch to link against libgcc_s intead of libgcc

[Jonathan Liu]

Signed-off-by: Jonathan Liu <net147@gmail.com>
---
 ...-libunwind-to-libgcc_s-rather-than-libgcc.patch | 42 ++++++++++++++++++++++
 meta/recipes-support/libunwind/libunwind_1.1.bb    |  1 +
 2 files changed, 43 insertions(+)
 create mode 100644 meta/recipes-support/libunwind/libunwind-1.1/Link-libunwind-to-libgcc_s-rather-than-libgcc.patch

diff --git a/meta/recipes-support/libunwind/libunwind-1.1/Link-libunwind-to-libgcc_s-rather-than-libgcc.patch b/meta/recipes-support/libunwind/libunwind-1.1/Link-libunwind-to-libgcc_s-rather-than-libgcc.patch
new file mode 100644
index 0000000..0e55c91
--- /dev/null
+++ b/meta/recipes-support/libunwind/libunwind-1.1/Link-libunwind-to-libgcc_s-rather-than-libgcc.patch
@@ -0,0 +1,42 @@
+From 508ca17a7be01d1cc960d9a07d0af4513948fb8d Mon Sep 17 00:00:00 2001
+From: Thierry Reding <treding@nvidia.com>
+Date: Fri, 27 Jun 2014 08:40:33 +0200
+Subject: [PATCH] Link libunwind to libgcc_s rather than libgcc
+
+For some architectures, -lgcc and -lgcc_s are not equivalent. On ARM for
+example, libgcc_s.so.1 contains some symbols needed by libunwind which
+are not present in libgcc.
+
+This causes the following link error when building the X.Org X server
+with libunwind support:
+
+	  CCLD     Xorg
+	/usr/lib/libunwind.so: undefined reference to `__aeabi_unwind_cpp_pr0'
+	/usr/lib/libunwind.so: undefined reference to `__aeabi_unwind_cpp_pr1'
+
+Linking against libgcc_s explicitly solves this problem.
+
+Upstream-Status: Backport
+
+Signed-off-by: Thierry Reding <treding@nvidia.com>
+Signed-off-by: Jonathan Liu <net147@gmail.com>
+---
+ configure.ac | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/configure.ac b/configure.ac
+index cffe19b..3beb5f2 100644
+--- a/configure.ac
++++ b/configure.ac
+@@ -258,7 +258,7 @@ AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[]], [[#ifndef __INTEL_COMPILER
+ 
+ if test x$GCC = xyes -a x$intel_compiler != xyes; then
+   CFLAGS="${CFLAGS} -fexceptions -Wall -Wsign-compare"
+-  LIBCRTS="-lgcc"
++  LIBCRTS="-lgcc_s"
+ fi
+ AC_MSG_RESULT([$intel_compiler])
+ 
+-- 
+2.3.2
+
diff --git a/meta/recipes-support/libunwind/libunwind_1.1.bb b/meta/recipes-support/libunwind/libunwind_1.1.bb
index 20db132..05dba3b 100644
--- a/meta/recipes-support/libunwind/libunwind_1.1.bb
+++ b/meta/recipes-support/libunwind/libunwind_1.1.bb
@@ -2,6 +2,7 @@ require libunwind.inc
 
 SRC_URI += "\
     file://Fix-test-case-link-failure-on-PowerPC-systems-with-Altivec.patch \
+    file://Link-libunwind-to-libgcc_s-rather-than-libgcc.patch \
 "
 
 SRC_URI[md5sum] = "fb4ea2f6fbbe45bf032cd36e586883ce"
-- 
2.3.1

Re: [dizzy][PATCH] libunwind: backport patch to link against libgcc_s intead of libgcc

[Khem Raj]

> On Mar 10, 2015, at 7:33 PM, Jonathan Liu <net147@gmail.com> wrote:
> 
> Signed-off-by: Jonathan Liu <net147@gmail.com>
> ---
> ...-libunwind-to-libgcc_s-rather-than-libgcc.patch | 42 ++++++++++++++++++++++
> meta/recipes-support/libunwind/libunwind_1.1.bb    |  1 +
> 2 files changed, 43 insertions(+)
> create mode 100644 meta/recipes-support/libunwind/libunwind-1.1/Link-libunwind-to-libgcc_s-rather-than-libgcc.patch
> 
> diff --git a/meta/recipes-support/libunwind/libunwind-1.1/Link-libunwind-to-libgcc_s-rather-than-libgcc.patch b/meta/recipes-support/libunwind/libunwind-1.1/Link-libunwind-to-libgcc_s-rather-than-libgcc.patch
> new file mode 100644
> index 0000000..0e55c91
> --- /dev/null
> +++ b/meta/recipes-support/libunwind/libunwind-1.1/Link-libunwind-to-libgcc_s-rather-than-libgcc.patch
> @@ -0,0 +1,42 @@
> +From 508ca17a7be01d1cc960d9a07d0af4513948fb8d Mon Sep 17 00:00:00 2001
> +From: Thierry Reding <treding@nvidia.com>
> +Date: Fri, 27 Jun 2014 08:40:33 +0200
> +Subject: [PATCH] Link libunwind to libgcc_s rather than libgcc
> +
> +For some architectures, -lgcc and -lgcc_s are not equivalent. On ARM for
> +example, libgcc_s.so.1 contains some symbols needed by libunwind which
> +are not present in libgcc.
> +
> +This causes the following link error when building the X.Org X server
> +with libunwind support:
> +
> +	  CCLD     Xorg
> +	/usr/lib/libunwind.so: undefined reference to `__aeabi_unwind_cpp_pr0'
> +	/usr/lib/libunwind.so: undefined reference to `__aeabi_unwind_cpp_pr1'
> +
> +Linking against libgcc_s explicitly solves this problem.
> +

have you tried it at runtime too ?

Re: [dizzy][PATCH] libunwind: backport patch to link against libgcc_s intead of libgcc

[Jonathan Liu]

On 11 March 2015 at 13:43, Khem Raj <raj.khem@gmail.com> wrote:
>
>> On Mar 10, 2015, at 7:33 PM, Jonathan Liu <net147@gmail.com> wrote:
>>
>> Signed-off-by: Jonathan Liu <net147@gmail.com>
>> ---
>> ...-libunwind-to-libgcc_s-rather-than-libgcc.patch | 42 ++++++++++++++++++++++
>> meta/recipes-support/libunwind/libunwind_1.1.bb    |  1 +
>> 2 files changed, 43 insertions(+)
>> create mode 100644 meta/recipes-support/libunwind/libunwind-1.1/Link-libunwind-to-libgcc_s-rather-than-libgcc.patch
>>
>> diff --git a/meta/recipes-support/libunwind/libunwind-1.1/Link-libunwind-to-libgcc_s-rather-than-libgcc.patch b/meta/recipes-support/libunwind/libunwind-1.1/Link-libunwind-to-libgcc_s-rather-than-libgcc.patch
>> new file mode 100644
>> index 0000000..0e55c91
>> --- /dev/null
>> +++ b/meta/recipes-support/libunwind/libunwind-1.1/Link-libunwind-to-libgcc_s-rather-than-libgcc.patch
>> @@ -0,0 +1,42 @@
>> +From 508ca17a7be01d1cc960d9a07d0af4513948fb8d Mon Sep 17 00:00:00 2001
>> +From: Thierry Reding <treding@nvidia.com>
>> +Date: Fri, 27 Jun 2014 08:40:33 +0200
>> +Subject: [PATCH] Link libunwind to libgcc_s rather than libgcc
>> +
>> +For some architectures, -lgcc and -lgcc_s are not equivalent. On ARM for
>> +example, libgcc_s.so.1 contains some symbols needed by libunwind which
>> +are not present in libgcc.
>> +
>> +This causes the following link error when building the X.Org X server
>> +with libunwind support:
>> +
>> +       CCLD     Xorg
>> +     /usr/lib/libunwind.so: undefined reference to `__aeabi_unwind_cpp_pr0'
>> +     /usr/lib/libunwind.so: undefined reference to `__aeabi_unwind_cpp_pr1'
>> +
>> +Linking against libgcc_s explicitly solves this problem.
>> +
>
> have you tried it at runtime too ?
>
strace 4.9 with libunwind PACKAGECONFIG wouldn't build on master
without the patch.
If I add strace 4.9 recipe to dizzy branch, using the libunwind
PACKAGECONFIG also fails to build without the patch. It gives the same
errors during linking.

I tested at runtime on master branch which has libunwind 1.1 running
strace 4.9 on the target and didn't notice any issues. I haven't
tested on dizzy branch at runtime though.

Regards,
Jonathan

Re: [dizzy][PATCH] libunwind: backport patch to link against libgcc_s intead of libgcc

[Khem Raj]

> On Mar 10, 2015, at 8:05 PM, Jonathan Liu <net147@gmail.com> wrote:
> 
> On 11 March 2015 at 13:43, Khem Raj <raj.khem@gmail.com> wrote:
>> 
>>> On Mar 10, 2015, at 7:33 PM, Jonathan Liu <net147@gmail.com> wrote:
>>> 
>>> Signed-off-by: Jonathan Liu <net147@gmail.com>
>>> ---
>>> ...-libunwind-to-libgcc_s-rather-than-libgcc.patch | 42 ++++++++++++++++++++++
>>> meta/recipes-support/libunwind/libunwind_1.1.bb    |  1 +
>>> 2 files changed, 43 insertions(+)
>>> create mode 100644 meta/recipes-support/libunwind/libunwind-1.1/Link-libunwind-to-libgcc_s-rather-than-libgcc.patch
>>> 
>>> diff --git a/meta/recipes-support/libunwind/libunwind-1.1/Link-libunwind-to-libgcc_s-rather-than-libgcc.patch b/meta/recipes-support/libunwind/libunwind-1.1/Link-libunwind-to-libgcc_s-rather-than-libgcc.patch
>>> new file mode 100644
>>> index 0000000..0e55c91
>>> --- /dev/null
>>> +++ b/meta/recipes-support/libunwind/libunwind-1.1/Link-libunwind-to-libgcc_s-rather-than-libgcc.patch
>>> @@ -0,0 +1,42 @@
>>> +From 508ca17a7be01d1cc960d9a07d0af4513948fb8d Mon Sep 17 00:00:00 2001
>>> +From: Thierry Reding <treding@nvidia.com>
>>> +Date: Fri, 27 Jun 2014 08:40:33 +0200
>>> +Subject: [PATCH] Link libunwind to libgcc_s rather than libgcc
>>> +
>>> +For some architectures, -lgcc and -lgcc_s are not equivalent. On ARM for
>>> +example, libgcc_s.so.1 contains some symbols needed by libunwind which
>>> +are not present in libgcc.
>>> +
>>> +This causes the following link error when building the X.Org X server
>>> +with libunwind support:
>>> +
>>> +       CCLD     Xorg
>>> +     /usr/lib/libunwind.so: undefined reference to `__aeabi_unwind_cpp_pr0'
>>> +     /usr/lib/libunwind.so: undefined reference to `__aeabi_unwind_cpp_pr1'
>>> +
>>> +Linking against libgcc_s explicitly solves this problem.
>>> +
>> 
>> have you tried it at runtime too ?
>> 
> strace 4.9 with libunwind PACKAGECONFIG wouldn't build on master
> without the patch.
> If I add strace 4.9 recipe to dizzy branch, using the libunwind
> PACKAGECONFIG also fails to build without the patch. It gives the same
> errors during linking.
> 
> I tested at runtime on master branch which has libunwind 1.1 running
> strace 4.9 on the target and didn't notice any issues. I haven't
> tested on dizzy branch at runtime though.

OK thanks, it would be interesting to see if exception handling in some binaries and shared objects is able to unwind through
to make sure this all works 

Re: [dizzy][PATCH] libunwind: backport patch to link against libgcc_s intead of libgcc

[Jonathan Liu]

On 11 March 2015 at 14:19, Khem Raj <raj.khem@gmail.com> wrote:
>
>> On Mar 10, 2015, at 8:05 PM, Jonathan Liu <net147@gmail.com> wrote:
>>
>> On 11 March 2015 at 13:43, Khem Raj <raj.khem@gmail.com> wrote:
>>>
>>>> On Mar 10, 2015, at 7:33 PM, Jonathan Liu <net147@gmail.com> wrote:
>>>>
>>>> Signed-off-by: Jonathan Liu <net147@gmail.com>
>>>> ---
>>>> ...-libunwind-to-libgcc_s-rather-than-libgcc.patch | 42 ++++++++++++++++++++++
>>>> meta/recipes-support/libunwind/libunwind_1.1.bb    |  1 +
>>>> 2 files changed, 43 insertions(+)
>>>> create mode 100644 meta/recipes-support/libunwind/libunwind-1.1/Link-libunwind-to-libgcc_s-rather-than-libgcc.patch
>>>>
>>>> diff --git a/meta/recipes-support/libunwind/libunwind-1.1/Link-libunwind-to-libgcc_s-rather-than-libgcc.patch b/meta/recipes-support/libunwind/libunwind-1.1/Link-libunwind-to-libgcc_s-rather-than-libgcc.patch
>>>> new file mode 100644
>>>> index 0000000..0e55c91
>>>> --- /dev/null
>>>> +++ b/meta/recipes-support/libunwind/libunwind-1.1/Link-libunwind-to-libgcc_s-rather-than-libgcc.patch
>>>> @@ -0,0 +1,42 @@
>>>> +From 508ca17a7be01d1cc960d9a07d0af4513948fb8d Mon Sep 17 00:00:00 2001
>>>> +From: Thierry Reding <treding@nvidia.com>
>>>> +Date: Fri, 27 Jun 2014 08:40:33 +0200
>>>> +Subject: [PATCH] Link libunwind to libgcc_s rather than libgcc
>>>> +
>>>> +For some architectures, -lgcc and -lgcc_s are not equivalent. On ARM for
>>>> +example, libgcc_s.so.1 contains some symbols needed by libunwind which
>>>> +are not present in libgcc.
>>>> +
>>>> +This causes the following link error when building the X.Org X server
>>>> +with libunwind support:
>>>> +
>>>> +       CCLD     Xorg
>>>> +     /usr/lib/libunwind.so: undefined reference to `__aeabi_unwind_cpp_pr0'
>>>> +     /usr/lib/libunwind.so: undefined reference to `__aeabi_unwind_cpp_pr1'
>>>> +
>>>> +Linking against libgcc_s explicitly solves this problem.
>>>> +
>>>
>>> have you tried it at runtime too ?
>>>
>> strace 4.9 with libunwind PACKAGECONFIG wouldn't build on master
>> without the patch.
>> If I add strace 4.9 recipe to dizzy branch, using the libunwind
>> PACKAGECONFIG also fails to build without the patch. It gives the same
>> errors during linking.
>>
>> I tested at runtime on master branch which has libunwind 1.1 running
>> strace 4.9 on the target and didn't notice any issues. I haven't
>> tested on dizzy branch at runtime though.
>
> OK thanks, it would be interesting to see if exception handling in some binaries and shared objects is able to unwind through
> to make sure this all works
>

Seems to work on dizzy branch too with strace 4.9 + libunwind 1.1 +
libunwind patch:
# strace -k uname 2>&1 | sed -n '/^write(1/,$p'
write(1, "Linux\n", 6Linux
)                  = 6
> /lib/libc-2.20.so(__write+0x1c) [0xbf8cc]
> /lib/libc-2.20.so(_IO_file_write+0x20) [0x69c10]
> /lib/libc-2.20.so(_IO_file_setbuf+0xd0) [0x690b8]
> /lib/libc-2.20.so(_IO_do_write+0x1c) [0x6ab20]
> /lib/libc-2.20.so(_IO_file_sync+0xc0) [0x68fb0]
> /lib/libc-2.20.so(fflush+0x8c) [0x5e1f4]
> /bin/busybox.nosuid(+0x0) [0x67178]
exit_group(0)                           = ?
+++ exited with 0 +++
> /lib/libc-2.20.so(_exit+0x10) [0x9a930]
> /lib/libc-2.20.so(__libc_secure_getenv+0xf8) [0x30dc8]
> /bin/busybox.nosuid(+0x0) [0x67194]

Regards,
Jonathan