Am 11.03.20 um 18:53 schrieb Theo Buehler:
> On Wed, Mar 11, 2020 at 04:12:56AM +0100, Jeremie Courreges-Anglas wrote:
>> On Tue, Mar 10 2020, Theo Buehler <t...@theobuehler.org> wrote:
>>> On Tue, Mar 10, 2020 at 06:35:04PM +0100, Jeremie Courreges-Anglas wrote:
>>>> On Mon, Mar 09 2020, Stuart Henderson <s...@spacehopper.org> wrote:
>>>>> On 2020/03/09 10:42, Theo Buehler wrote:
>>>>>> On Mon, Jan 13, 2020 at 12:50:32PM +0000, Stuart Henderson wrote:
>>>>>>> 2/3 through a bulk build and I see that this breaks scipy (missing
>>>>>>> symbols,
>>>>>>> blas/cblas-related) so needs a bit more work, but I think it's generally
>>>>>>> along the right lines.
>>>>>>
>>>>>> Not sure if this provides any useful clue, but py-numpy doesn't build at
>>>>>> all on sparc64 with this diff, also due to missing blas/cblas symbols:
>>>>>
>>>>> You'll probably see the same on amd64 with USE_LLD=no.
>>>>
>>>> I managed to build scipy with no changes on amd64, so I'm not sure what
>>>> the problem is on this arch (did not try with USE_LLD=No).
>>>>
>>>> However I took a look at the issue reported by tb on sparc64.
>>>>
>>>> --8<--
>>>> creating /tmp/tmpKcZ0cd/tmp
>>>> creating /tmp/tmpKcZ0cd/tmp/tmpKcZ0cd
>>>> compile options: '-I/usr/local/include -I/usr/include -c'
>>>> cc: /tmp/tmpKcZ0cd/source.c
>>>> cc /tmp/tmpKcZ0cd/tmp/tmpKcZ0cd/source.o -L/usr/local/lib -lcblas -o
>>>> /tmp/tmpKcZ0cd/a.out
>>>> /usr/local/lib/libcblas.so.1.0: undefined reference to `ztbsv_'
>>>> /usr/local/lib/libcblas.so.1.0: undefined reference to `dasum_'
>>>>
>>>> [...]
>>>>
>>>> /usr/local/lib/libcblas.so.1.0: undefined reference to `zsymm_'
>>>> /usr/local/lib/libcblas.so.1.0: undefined reference to `ztrsm_'
>>>> /usr/local/lib/libcblas.so.1.0: undefined reference to `sswap_'
>>>> collect2: error: ld returned 1 exit status
>>>> cc /tmp/tmpKcZ0cd/tmp/tmpKcZ0cd/source.o -L/usr/local/lib -lblas -o
>>>> /tmp/tmpKcZ0cd/a.out
>>>> /tmp/tmpKcZ0cd/tmp/tmpKcZ0cd/source.o: In function `main':
>>>> source.c:(.text.startup+0xdc): undefined reference to `cblas_ddot'
>>>> collect2: error: ld returned 1 exit status
>>>> -->8--
>>>>
>>>> libcblas.so doesn't depend on libblas.so so missing symbols are to be
>>>> expected if one links with -lcblas instead of -lcblas -lblas. The
>>>> second linking test fails because libblas.so doesn't provide cblas
>>>> symbols.
>>>
>>> Thanks, this makes sense. But why does this work with ld.lld?
>>
>> ld.lld doesn't bother checking that all symbols in libcblas.so can be
>> resolved, ld.bfd does. This means that if you link against a library
>> that references a bogus symbol or lacks some library interdependency
>> (DT_NEEDED) you only get a crash at run time.
>>
>> On amd64, using the testcase from numpy:
>>
>> --8<--
>> russell /tmp$ cat r.c
>> #include <cblas.h>
>> int main(int argc, const char *argv[])
>> {
>> double a[4] = {1,2,3,4};
>> double b[4] = {5,6,7,8};
>> return cblas_ddot(4, a, 1, b, 1) > 10;
>> }
>> russell /tmp$ cc -I/usr/local/include r.c -L/usr/local/lib -lcblas
>> russell /tmp$ ./a.out
>> a.out:/usr/local/lib/libcblas.so.1.0: undefined symbol 'ddot_'
>> ld.so: a.out: lazy binding failed!
>> Killed
>> -->8--
>>
>> I suspect Stuart hit a similar problem with this numpy update and scipy.
>>
>> Using -fuse-ld=bfd in the testcase above would result in the same errors
>> as in your log.
>
> I see. Thank you very much for your explanations.
>
> FWIW your cblas diff is ok tb (also tested on macppc).
>
Also tested on arm64, with numpy-1.16.6:
42 failed, 7268 passed, 93 skipped, 168 deselected, 12 xfailed, 1
xpassed, 1 warnings
I think this is ready to go into the tree with the cblas diff on top?
The update to 1.16.6 is straightforward if you want to stick to 1.16.5 now.
-m
