These are the packages that would be merged, in order:

Calculating dependencies ... done!
Dependency resolution took 1.16 s (backtrack: 0/20).

[ebuild  N     ] dev-build/b2-5.5.3::gentoo  USE="-examples" 1198 KiB
[ebuild  N     ] dev-libs/libaio-0.3.113_p8::gentoo  USE="-static-libs -test" 74 KiB
[ebuild  N     ] dev-cpp/gflags-2.2.2-r1:0/2.2::gentoo  USE="-static-libs -test" 97 KiB
[ebuild  N     ] dev-cpp/gtest-1.17.0:0/1.17.0::gentoo  USE="(-abseil) -doc -examples -test" 865 KiB
[ebuild  N     ] app-arch/lz4-1.10.0-r1:0/1.10.0-meson::gentoo  USE="-static-libs -test" 379 KiB
[ebuild  N     ] app-arch/snappy-1.2.2-r1:0/1.1::gentoo  USE="-test" CPU_FLAGS_X86="avx avx2" 1083 KiB
[ebuild  N     ] dev-cpp/fast_float-8.0.2::gentoo  USE="-test" 119 KiB
[ebuild  N     ] dev-libs/double-conversion-3.4.0:0/3::gentoo  USE="-test" 6871 KiB
[ebuild  N     ] sys-libs/liburing-2.15:0/2::gentoo  USE="-examples -static-libs -test" 538 KiB
[ebuild  N     ] dev-cpp/glog-0.6.0-r1:0/1::gentoo  USE="gflags libunwind -llvm-libunwind -test" 189 KiB
[ebuild  N     ] dev-libs/boost-1.91.0-r2:0/1.91.0::gentoo  USE="bzip2 context nls python stacktrace zlib -debug -doc -icu -lzma -mpi -numpy -test -test-full -tools -zstd" PYTHON_TARGETS="python3_14 -python3_12 -python3_13" 199785 KiB
[ebuild  N     ] dev-cpp/folly-2024.11.04.00-r2:0/2024.11.04.00::gentoo  USE="-llvm-libunwind -test" 4088 KiB
[ebuild  N     ] dev-cpp/fizz-2024.11.04.00:0/2024.11.04.00::gentoo  USE="-test" 720 KiB
[ebuild  N     ] dev-cpp/wangle-2024.11.04.00:0/2024.11.04.00::gentoo  USE="-test" 365 KiB
[ebuild  N     ] dev-cpp/mvfst-2024.11.04.00-r1:0/2024.11.04.00::gentoo  USE="-test" 1938 KiB
[ebuild  N     ] dev-cpp/fbthrift-2024.11.04.00-r1:0/2024.11.04.00::gentoo  USE="-test" 15178 KiB
[ebuild  N     ] dev-cpp/fb303-2024.11.04.00:0/2024.11.04.00::gentoo  USE="-test" 251 KiB
[ebuild  N     ] dev-cpp/edencommon-2024.11.04.00:0/2024.11.04.00::gentoo  USE="-llvm-libunwind" 305 KiB

Total: 18 packages (18 new), Size of downloads: 234034 KiB

The following USE changes are necessary to proceed:
 (see "package.use" in the portage(5) man page for more details)
# required by dev-cpp/wangle-2024.11.04.00::gentoo
# required by dev-cpp/fb303-2024.11.04.00::gentoo
# required by dev-cpp/edencommon-2024.11.04.00::gentoo
# required by =dev-cpp/edencommon-2024.11.04.00 (argument)
>=dev-cpp/glog-0.6.0-r1 gflags