[FFmpeg-devel] [PATCH] configure: make sure LTO does not optimize out the test functions

[Andreas Cadhalpun]

On 26.10.2016 02:07, Michael Niedermayer wrote:
> On Wed, Oct 26, 2016 at 01:35:34AM +0200, Andreas Cadhalpun wrote:
>> On 26.10.2016 01:26, Michael Niedermayer wrote:
>>> On Wed, Oct 26, 2016 at 01:16:13AM +0200, Andreas Cadhalpun wrote:
>>>>  configure |    7 ++++++-
>>>>  1 file changed, 6 insertions(+), 1 deletion(-)
>>>> 742684cf379693d08075d43fdfb75ed5e2e936c6  0001-configure-make-sure-LTO-does-not-optimize-out-the-te.patch
>>>> From bb289a0b2b0948afa99227bcff188301c1143624 Mon Sep 17 00:00:00 2001
>>>> From: Andreas Cadhalpun <Andreas.Cadhalpun at googlemail.com>
>>>> Date: Tue, 25 Oct 2016 19:09:46 +0200
>>>> Subject: [PATCH] configure: make sure LTO does not optimize out the test
>>>>  functions
>>>>
>>>> Fixes trac ticket #5909
>>>>
>>>> Bud-Id: https://bugs.gentoo.org/show_bug.cgi?id=598054
>>>> Signed-off-by: Andreas Cadhalpun <Andreas.Cadhalpun at googlemail.com>
>>>> ---
>>>>  configure | 7 ++++++-
>>>>  1 file changed, 6 insertions(+), 1 deletion(-)
>>>>
>>>> diff --git a/configure b/configure
>>>> index 481f692..54faef1 100755
>>>> --- a/configure
>>>> +++ b/configure
>>>> @@ -1150,7 +1150,12 @@ check_func_headers(){
>>>>          for func in $funcs; do
>>>>              echo "long check_$func(void) { return (long) $func; }"
>>>>          done
>>>> -        echo "int main(void) { return 0; }"
>>>> +        echo "int main(void) { int ret = 0;"
>>>> +        # LTO could optimize out the test functions without this
>>>> +        for func in $funcs; do
>>>> +            echo " ret |= ((intptr_t)check_$func) & 0xFFFF;"
>>>> +        done
>>>> +        echo "return ret; }"
>>>
>>> breaks configure
>>>
>>> i get this:
>>>
>>> ERROR: LoadLibrary/dlopen not found for avisynth
>>
>> I forgot to include stdint.h. Fixed patch attached.
> 
> seems working here now
> 
> Acked-by: Michael

Pushed.

Best regards,
Andreas