On Wed, Mar 15, 2017 at 9:10 PM, Jonathan Wakely <jwakely.gcc@xxxxxxxxx> wrote:
> On 15 March 2017 at 19:45, Manuel Lauss wrote:
>> Hello,
>>
>> I'm trying to build a current mesa git shapshot with LTO,
>> and it fails with this error in src/compiler/: (gcc-6.3.1 as of
>> today, glibc-2.25)
>>
>> x86_64-pc-linux-gnu-g++ -m32 -fvisibility=hidden -Werror=pointer-arith
>> -Werror=vla -O3 -march=haswell -mtune=haswell-flto=9
>> -fno-fat-lto-objects -pipe -Wall -fno-math-errno -fno-trapping-math
>> -Wl,-O1 -o glsl_compiler glsl/main.o -Wl,--as-needed
>> glsl/.libs/libstandalone.a -lz -lpthread
>> /usr/lib/gcc/x86_64-pc-linux-gnu/6.3.0/32/libstdc++.so: undefined
>> reference to `pthread_create'
>> /usr/lib/gcc/x86_64-pc-linux-gnu/6.3.0/32/libstdc++.so: undefined
>> reference to `pthread_once'
>> /usr/lib/gcc/x86_64-pc-linux-gnu/6.3.0/32/libstdc++.so: undefined
>> reference to `pthread_join'
>>
>> Any ideas why pthread_once() can't be found? /lib32/libpthread.so does
>> have all the above mentioned symbols. Without LTO, it builds just fine
>> (however performance of the library suffers, lto helps mesa a lot).
>
> Does it help if you put -Wl,--no-as-needed before -lpthread?
Yes it does, thanks a lot!
Manuel
