ungoogled-chromium: linux build fails because of template issue in third_party/webrtc/rtc_base/bitstream_reader.h

Describe the bug Linux build fails with the following errors:

In file included from ../../third_party/webrtc/rtc_base/bitstream_reader.cc:11:
../../third_party/webrtc/rtc_base/bitstream_reader.h:70:13: error: explicit specialization in non-namespace scope 'class webrtc::BitstreamReader'
   70 |   template <>
      |             ^
../../third_party/webrtc/rtc_base/bitstream_reader.h:71:29: error: template-id 'Read<bool>' in declaration of primary template
   71 |   ABSL_MUST_USE_RESULT bool Read<bool>() {
      |                             ^~~~~~~~~~

To Reproduce Steps to reproduce the behavior:

1. Download source files
2. Run build using the RPM SPEC file successfully used to build Ungoogled-chromium 94.xxxx
3. Build fails at [10335/49258]
4. See error

Expected behavior Keep building

Screenshots Full command line and related error:

[10335/49258] CXX obj/third_party/webrtc/rtc_base/bitstream_reader/bitstream_reader.o
FAILED: obj/third_party/webrtc/rtc_base/bitstream_reader/bitstream_reader.o 
x86_64-mageia-linux-gnu-g++ -MMD -MF obj/third_party/webrtc/rtc_base/bitstream_reader/bitstream_reader.o.d -DUSE_UDEV -DUSE_AURA=1 -DUSE_GLIB=1 -DUSE_NSS_CERTS=1 -DUSE_OZONE=1 -DUSE_X11=1 -D_FILE_OFFSET_BITS=64 -D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -DNO_UNWIND_TABLES -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -DNDEBUG -DNVALGRIND -DDYNAMIC_ANNOTATIONS_ENABLED=0 -DWEBRTC_ENABLE_PROTOBUF=1 -DRTC_ENABLE_VP9 -DWEBRTC_HAVE_SCTP -DENABLE_EXTERNAL_AUTH -DWEBRTC_USE_H264 -DHAVE_WEBRTC_VIDEO -DLOGGING_INSIDE_WEBRTC -DWEBRTC_LIBRARY_IMPL -DWEBRTC_NON_STATIC_TRACE_EVENT_HANDLERS=0 -DWEBRTC_CHROMIUM_BUILD -DWEBRTC_POSIX -DWEBRTC_LINUX -DABSL_ALLOCATOR_NOTHROW=1 -I../.. -Igen -I../../third_party/webrtc_overrides -I../../third_party/webrtc -Igen/third_party/webrtc -I../../third_party/abseil-cpp -fno-ident -fno-strict-aliasing --param=ssp-buffer-size=4 -fstack-protector -fno-unwind-tables -fno-asynchronous-unwind-tables -fPIC -pipe -pthread -Wno-builtin-macro-redefined -D__DATE__= -D__TIME__= -D__TIMESTAMP__= -Wall -Wno-unused-local-typedefs -Wno-deprecated-declarations -Wno-comments -Wno-packed-not-aligned -Wno-missing-field-initializers -Wno-unused-parameter -fno-omit-frame-pointer -fvisibility=hidden -std=gnu++14 -Wno-narrowing -Wno-class-memaccess -fno-exceptions -fno-rtti -fvisibility-inlines-hidden -O2 -pipe -Wformat -Werror=format-security -Wp,-D_FORTIFY_SOURCE=2 -fstack-protector --param=ssp-buffer-size=4 -fasynchronous-unwind-tables -faligned-new -Wno-attributes -Wno-ignored-attributes -Wno-error=class-memaccess -Wno-error=unknown-pragmas -Wno-error=array-bounds -Wno-return-type -Wno-error=nonnull -Wno-error=free-nonheap-object -Wno-error=unused -Wno-error=unused-function -Wno-error=unused-variable -Wno-error=unused-but-set-variable -Wno-error=maybe-uninitialized -Wno-error=uninitialized -Wno-error=invalid-offsetof -Wno-error=stringop-overflow -std=gnu++17 -fpermissive -w -Wno-error=format-truncation -c ../../third_party/webrtc/rtc_base/bitstream_reader.cc -o obj/third_party/webrtc/rtc_base/bitstream_reader/bitstream_reader.o
In file included from ../../third_party/webrtc/rtc_base/bitstream_reader.cc:11:
../../third_party/webrtc/rtc_base/bitstream_reader.h:70:13: error: explicit specialization in non-namespace scope 'class webrtc::BitstreamReader'
   70 |   template <>
      |             ^
../../third_party/webrtc/rtc_base/bitstream_reader.h:71:29: error: template-id 'Read<bool>' in declaration of primary template
   71 |   ABSL_MUST_USE_RESULT bool Read<bool>() {
      |                             ^~~~~~~~~~

Environment (please complete the following information):

• OS/Platform and version: Mageia 8 x64
• ungoogled-chromium version: 95.0.4638.54
• gcc version: output of gcc -v

Utilisation des specs internes.
COLLECT_GCC=gcc
COLLECT_LTO_WRAPPER=/usr/lib/gcc/x86_64-mageia-linux-gnu/10/lto-wrapper
Cible : x86_64-mageia-linux-gnu
Configuré avec: ../configure --prefix=/usr --libexecdir=/usr/lib --with-slibdir=/lib64 --with-pkgversion='Mageia 10.3.0-2.mga8' --with-bugurl=https://bugs.mageia.org/ --mandir=/usr/share/man --infodir=/usr/share/info --enable-checking=release --enable-languages=c,c++,ada,fortran,objc,obj-c++,d --enable-linker-build-id --build=x86_64-mageia-linux-gnu --host=x86_64-mageia-linux-gnu --with-cpu=generic --with-system-zlib --enable-threads=posix --with-linker-hash-style=gnu --enable-shared --enable-long-long --enable-__cxa_atexit --disable-libunwind-exceptions --enable-clocale=gnu --enable-ssp --disable-libssp --disable-libffi --disable-werror --with-isl --with-python-dir=/lib/python3.8/site-packages --enable-lto --with-gcc-major-version-only
Modèle de thread: posix
Algorithmes de compression LTO supportés: zlib zstd
gcc version 10.3.0 (Mageia 10.3.0-2.mga8) 

Additional context Hi with the same spec file (beside patch adjustments to cope with code changes in version 95), I have successfully packaged 94.0.4606.81 and 94.0.4606.61 third_party/webrtc/rtc_base/bitstream_reader.cc seems a new addition with Chromium 95 My distribution has not packaged this 95 version yet. So, it might not be an ungoogled-chromium related issue. However, before reporting a bug upstream to Chromium, I’d like to make sure it is unlikely related to ungoogled-chromium. Plus, if you have some ideas how to solve this, it might save me some time 😉

Thanks!