Compile error with glibc 2.26

[bermond]

Compiling with the newly released gblic 2.26 gives me the following error:

CC      libavfilter/vf_sab.o
CC      libavfilter/vf_scale.o
CC      libavfilter/vf_scale_cuda.o
NVCC    libavfilter/vf_scale_cuda.ptx
CC      libavfilter/vf_scale_npp.o
/usr/include/bits/floatn.h(61): error: invalid argument to attribute "__mode__"

/usr/include/bits/floatn.h(73): error: identifier "__float128" is undefined

CC      libavfilter/vf_scale_qsv.o
CC      libavfilter/vf_scale_vaapi.o
2 errors detected in the compilation of "/tmp/tmpxft_000034b7_00000000-7_vf_scale_cuda.cpp1.ii".
make: *** [ffbuild/common.mak:95: libavfilter/vf_scale_cuda.ptx] Error 2
make: *** Waiting for unfinished jobs....
libavfilter/vf_paletteuse.c: In function ‘load_apply_palette’:
libavfilter/vf_paletteuse.c:970:14: warning: ‘main’ is usually a function [-Wmain]
     AVFrame *main, *second, *out;
              ^~~~

How to reproduce:

$ ./configure \
        --prefix='/usr' \
        --extra-cflags='-I/opt/cuda/include' \
        --extra-ldflags='-L/opt/cuda/lib64 -Wl,-rpath -Wl,/opt/intel/mediasdk/lib64' \
        \
        --cpu='native' \
        \
        --enable-rpath \
        --enable-gpl \
        --enable-version3 \
        --enable-nonfree \
        --enable-shared \
        --disable-static \
        --enable-gray \
        --enable-avresample \
        \
        --enable-alsa \
        --enable-avisynth \
        --enable-bzlib \
        --enable-chromaprint \
        --enable-frei0r \
        --enable-gcrypt \
        --enable-gmp \
        --enable-gnutls \
        --enable-iconv \
        --enable-jack \
        --enable-ladspa \
        --enable-libass \
        --enable-libbluray \
        --enable-libbs2b \
        --enable-libcaca \
        --enable-libcelt \
        --enable-libcdio \
        --enable-libdc1394 \
        --enable-libfdk-aac \
        --enable-libflite \
        --enable-fontconfig \
        --enable-libfreetype \
        --enable-libfribidi \
        --enable-libgme \
        --enable-libgsm \
        --enable-libiec61883 \
        --enable-libilbc \
        --enable-libkvazaar \
        --enable-libmodplug \
        --enable-libmp3lame \
        --enable-libopencore-amrnb \
        --enable-libopencore-amrwb \
        --enable-libopencv \
        --enable-libopenh264 \
        --enable-libopenjpeg \
        --enable-libopenmpt \
        --enable-libopus \
        --enable-libpulse \
        --enable-librsvg \
        --enable-librubberband \
        --enable-librtmp  \
        --enable-libshine \
        --enable-libsmbclient \
        --enable-libsnappy \
        --enable-libsoxr \
        --enable-libspeex \
        --enable-libssh \
        --enable-libtesseract \
        --enable-libtheora \
        --enable-libtwolame \
        --enable-libv4l2 \
        --enable-libvidstab \
        --enable-libvmaf \
        --enable-libvo-amrwbenc \
        --enable-libvorbis \
        --enable-libvpx \
        --enable-libwavpack \
        --enable-libwebp \
        --enable-libx264 \
        --enable-libx265 \
        --enable-libxavs \
        --enable-libxcb \
        --enable-libxcb-shm \
        --enable-libxcb-xfixes \
        --enable-libxcb-shape \
        --enable-libxvid \
        --enable-libzimg \
        --enable-libzmq \
        --enable-libzvbi \
        --enable-lzma \
        --enable-decklink \
        --enable-libndi_newtek \
        --enable-libmysofa \
        --enable-openal \
        --enable-opencl \
        --enable-opengl \
        --enable-openssl \
        --enable-sndio \
        --enable-sdl2 \
        --enable-xlib \
        --enable-zlib \
        \
        --enable-cuda \
        --enable-cuda-sdk \
        --enable-cuvid \
        --enable-libmfx \
        --enable-libnpp \
        --enable-nvenc \
        --enable-omx \
        --enable-omx-rpi \
        --enable-vaapi \
        --enable-vdpau
$ make -j6

When downgrading glibc to 2.25 it compiles fine.

System information:
OS: Arch Linux x86_64
FFmpeg: git master (currently at N-87251: 3.4.r87251.ga918f16f7c)
Compiler: gcc 7.2.0
glibc: 2.26
CUDA: 8.0.61

Relevant system-wide environmet variables:
CPPFLAGS="-D_FORTIFY_SOURCE=2"
CFLAGS="-march=native -O2 -pipe -fstack-protector-strong -fno-plt"
CXXFLAGS="-march=native -O2 -pipe -fstack-protector-strong -fno-plt"
LDFLAGS="-Wl,-O1,--sort-common,--as-needed,-z,relro,-z,now"

[bermond]

A temporary workaround is to use --disable-cuda-sdk.

[Timo R.]

That error is coming from nvcc, not ffmpeg or any of ffmpegs code.
Nothing we could possibly do about it. Ask nvidia to update their CUDA compiler for compatibility with the new glibc.
Maybe try SDK 9.

[bermond]

@oromit
Thank you for the reply and clarification.