telegram-desktop will crash when loading vp9 contents if ffmpeg emerged without libvpx. In the source code file tdesktop/Telegram/SourceFiles/ffmpeg/ffmpeg_utility.cpp: const AVCodec *FindDecoder(not_null<AVCodecContext*> context) { // Force libvpx-vp9, because we need alpha channel support. return (context->codec_id == AV_CODEC_ID_VP9) ? avcodec_find_decoder_by_name("libvpx-vp9") : avcodec_find_decoder(context->codec_id); } It force libvpx-vp9, so if emerge ffmpeg without libvpx, AVCodec will be nullptr, which will cause segmentation fault.
I confirm it. Without "vpx" ffmpeg USE flag: Thread 7 "telegram-deskto" received signal SIGSEGV, Segmentation fault. [Switching to Thread 0x7fffdfc0a6c0 (LWP 8220)] 0x00007ffff5f2573e in avcodec_receive_frame () from /usr/lib64/libavcodec.so.58 (gdb) bt #0 0x00007ffff5f2573e in avcodec_receive_frame () at /usr/lib64/libavcodec.so.58 #1 0x0000555556a0cb7c in FFmpeg::FrameGenerator::Impl::readNextFrame() (this=0x7fffd40070b0) at /var/tmp/portage-ondisk/portage/net-im/telegram-desktop-4.3.4-r1/work/tdesktop-4.3.4-full/Telegram/SourceFiles/ffmpeg/ffmpeg_frame_generator.cpp:313 #2 0x0000555556a0c4f5 in FFmpeg::FrameGenerator::Impl::renderNext(QImage, QSize, Qt::AspectRatioMode) (this=0x7fffd40070b0, storage=<incomplete type>, size=..., mode=Qt::KeepAspectRatio) at /var/tmp/portage-ondisk/portage/net-im/telegram-desktop-4.3.4-r1/work/tdesktop-4.3.4-full/Telegram/SourceFiles/ffmpeg/ffmpeg_frame_generator.cpp:258 #3 0x0000555556a0d333 in FFmpeg::FrameGenerator::renderNext(QImage, QSize, Qt::AspectRatioMode) (this=0x7fffd8044800, storage=<incomplete type>, size=..., mode=Qt::KeepAspectRatio) at /var/tmp/portage-ondisk/portage/net-im/telegram-desktop-4.3.4-r1/work/tdesktop-4.3.4-full/Telegram/SourceFiles/ffmpeg/ffmpeg_frame_generator.cpp:395 #4 0x000055555b145e97 in operator()() (__closure=0x555561488190) at /var/tmp/portage-ondisk/portage/net-im/telegram-desktop-4.3.4-r1/work/tdesktop-4.3.4-full/Telegram/lib_ui/ui/text/custom_emoji_instance.cpp:459 #5 0x000055555b14baab in operator()(void*) const (__closure=0x7fffdfc09287, passed=0x555561488190) at /var/tmp/portage-ondisk/portage/net-im/telegram-desktop-4.3.4-r1/work/tdesktop-4.3.4-full/Telegram/lib_crl/crl/dispatch/crl_dispatch_async.h:51 #6 0x000055555b14c4a5 in crl::details::EmptyWrapper::Invoke<crl::details::on_queue_invoke<EmptyWrapper, void (*)(void*, void (*)(void*), void*), Ui::CustomEmoji::Renderer::Renderer(Ui::CustomEmoji::RendererDescriptor&&)::<lambda()> >(void*, void (*)(void*, void (*)(void*), void*), Ui::CustomEmoji::Renderer::Renderer(Ui::CustomEmoji::RendererDescriptor&&)::<lambda()>&&)::<lambda(void*)>::<lambda(void*)> >(struct {...} &&, void *) (callable=..., argument=0x555561488190) at /var/tmp/portage-ondisk/portage/net-im/telegram-desktop-4.3.4-r1/work/tdesktop-4.3.4-full/Telegram/lib_crl/crl/dispatch/crl_dispatch_async.h:60 #7 0x000055555b14bb20 in operator()(void*) const (__closure=0x0, passed=0x555561488190) at /var/tmp/portage-ondisk/portage/net-im/telegram-desktop-4.3.4-r1/work/tdesktop-4.3.4-full/Telegram/lib_crl/crl/dispatch/crl_dispatch_async.h:48 #8 0x000055555b14bb54 in _FUN(void*) () at /var/tmp/portage-ondisk/portage/net-im/telegram-desktop-4.3.4-r1/work/tdesktop-4.3.4-full/Telegram/lib_crl/crl/dispatch/crl_dispatch_async.h:47 #9 0x00007ffff579793a in () at /usr/lib64/libdispatch.so #10 0x00007ffff3550845 in start_thread () at /lib64/libc.so.6 #11 0x00007ffff35d036c in clone3 () at /lib64/libc.so.6 It seems, the segfault occurs at attempt to display a sticker from the "Roflmoji" pack. After rebuilding ffmpeg with the "vpx" USE flag the problem gone. xiaoming, thank you for your report! It saves a lot of my time for trying different USE flags.
*** Bug 891755 has been marked as a duplicate of this bug. ***
The bug has been closed via the following commit(s): https://gitweb.gentoo.org/repo/gentoo.git/commit/?id=19bd77e8f59cc673936cbf52bd1eb749ddc1269f commit 19bd77e8f59cc673936cbf52bd1eb749ddc1269f Author: Esteve Varela Colominas <esteve.varela@gmail.com> AuthorDate: 2023-02-16 15:42:57 +0000 Commit: Georgy Yakovlev <gyakovlev@gentoo.org> CommitDate: 2023-02-22 22:57:00 +0000 net-im/telegram-desktop: Bump to 4.6.3 Closes: https://bugs.gentoo.org/888637 Closes: https://bugs.gentoo.org/891755 Thanks-to: xiaoming <xiangluoming2015@outlook.com> Thanks-to: Alexander Turenko <totktonada.ru@gmail.com> Thanks-to: Erik <esigra@gmail.com> Thanks-to: Egor <egorr.berd@gmail.com> Signed-off-by: Esteve Varela Colominas <esteve.varela@gmail.com> Signed-off-by: Georgy Yakovlev <gyakovlev@gentoo.org> net-im/telegram-desktop/Manifest | 1 + net-im/telegram-desktop/metadata.xml | 4 +- .../telegram-desktop/telegram-desktop-4.6.3.ebuild | 206 +++++++++++++++++++++ 3 files changed, 209 insertions(+), 2 deletions(-)
