community/abseil-cpp broken with gcc

currently built abseil-cpp is missing a bunch of symbols in its .so's, and so programs linked against it fail. for instance:

< ldd /usr/lib/libgrpc.so.21
	/lib/ld-musl-x86_64.so.1 (0x7f27cbbe0000)
	libz.so.1 => /lib/libz.so.1 (0x7f27cb80c000)
	libcares.so.2 => /usr/lib/libcares.so.2 (0x7f27cb7f6000)
	libabsl_statusor.so.2103.0.1 => /usr/lib/libabsl_statusor.so.2103.0.1 (0x7f27cb7f0000)
	libgpr.so.21 => /usr/lib/libgpr.so.21 (0x7f27cb7d7000)
	libssl.so.1.1 => /lib/libssl.so.1.1 (0x7f27cb755000)
	libcrypto.so.1.1 => /lib/libcrypto.so.1.1 (0x7f27cb4d5000)
	libaddress_sorting.so.21 => /usr/lib/libaddress_sorting.so.21 (0x7f27cb4d0000)
	libre2.so.9 => /usr/lib/libre2.so.9 (0x7f27cb486000)
	libabsl_hash.so.2103.0.1 => /usr/lib/libabsl_hash.so.2103.0.1 (0x7f27cb481000)
	libabsl_bad_variant_access.so.2103.0.1 => /usr/lib/libabsl_bad_variant_access.so.2103.0.1 (0x7f27cb47c000)
	libupb.so.21 => /usr/lib/libupb.so.21 (0x7f27cb45f000)
	libabsl_status.so.2103.0.1 => /usr/lib/libabsl_status.so.2103.0.1 (0x7f27cb455000)
	libabsl_cord.so.2103.0.1 => /usr/lib/libabsl_cord.so.2103.0.1 (0x7f27cb440000)
	libabsl_bad_optional_access.so.2103.0.1 => /usr/lib/libabsl_bad_optional_access.so.2103.0.1 (0x7f27cb43b000)
	libabsl_str_format_internal.so.2103.0.1 => /usr/lib/libabsl_str_format_internal.so.2103.0.1 (0x7f27cb426000)
	libabsl_synchronization.so.2103.0.1 => /usr/lib/libabsl_synchronization.so.2103.0.1 (0x7f27cb416000)
	libabsl_time.so.2103.0.1 => /usr/lib/libabsl_time.so.2103.0.1 (0x7f27cb404000)
	libabsl_strings.so.2103.0.1 => /usr/lib/libabsl_strings.so.2103.0.1 (0x7f27cb3ec000)
	libabsl_throw_delegate.so.2103.0.1 => /usr/lib/libabsl_throw_delegate.so.2103.0.1 (0x7f27cb3e5000)
	libabsl_time_zone.so.2103.0.1 => /usr/lib/libabsl_time_zone.so.2103.0.1 (0x7f27cb3cf000)
	libstdc++.so.6 => /usr/lib/libstdc++.so.6 (0x7f27cb1f7000)
	libgcc_s.so.1 => /usr/lib/libgcc_s.so.1 (0x7f27cb1de000)
	libc.musl-x86_64.so.1 => /lib/ld-musl-x86_64.so.1 (0x7f27cbbe0000)
	libabsl_raw_logging_internal.so.2103.0.1 => /usr/lib/libabsl_raw_logging_internal.so.2103.0.1 (0x7f27cb1d9000)
	libabsl_spinlock_wait.so.2103.0.1 => /usr/lib/libabsl_spinlock_wait.so.2103.0.1 (0x7f27cb1d4000)
	libabsl_city.so.2103.0.1 => /usr/lib/libabsl_city.so.2103.0.1 (0x7f27cb1cf000)
	libabsl_wyhash.so.2103.0.1 => /usr/lib/libabsl_wyhash.so.2103.0.1 (0x7f27cb1ca000)
	libabsl_int128.so.2103.0.1 => /usr/lib/libabsl_int128.so.2103.0.1 (0x7f27cb1c3000)
	libabsl_stacktrace.so.2103.0.1 => /usr/lib/libabsl_stacktrace.so.2103.0.1 (0x7f27cb1be000)
	libabsl_symbolize.so.2103.0.1 => /usr/lib/libabsl_symbolize.so.2103.0.1 (0x7f27cb1b9000)
	libabsl_malloc_internal.so.2103.0.1 => /usr/lib/libabsl_malloc_internal.so.2103.0.1 (0x7f27cb1b2000)
	libabsl_base.so.2103.0.1 => /usr/lib/libabsl_base.so.2103.0.1 (0x7f27cb1ac000)
	libabsl_strings_internal.so.2103.0.1 => /usr/lib/libabsl_strings_internal.so.2103.0.1 (0x7f27cb1a6000)
	libabsl_debugging_internal.so.2103.0.1 => /usr/lib/libabsl_debugging_internal.so.2103.0.1 (0x7f27cb1a1000)
Error relocating /usr/lib/libgpr.so.21: _ZNK4absl12lts_202103246Status10GetPayloadENS0_11string_viewE: symbol not found
Error relocating /usr/lib/libgpr.so.21: _ZN4absl12lts_202103244CordC1ENS0_11string_viewE: symbol not found
Error relocating /usr/lib/libgpr.so.21: _ZN4absl12lts_202103246StatusC1ENS0_10StatusCodeENS0_11string_viewE: symbol not found
Error relocating /usr/lib/libgpr.so.21: _ZN4absl12lts_2021032410CHexEscapeB5cxx11ENS0_11string_viewE: symbol not found
Error relocating /usr/lib/libgpr.so.21: _ZN4absl12lts_202103246Status10SetPayloadENS0_11string_viewENS0_4CordE: symbol not found
Error relocating /usr/lib/libgpr.so.21: _ZN4absl12lts_2021032417optional_internal25throw_bad_optional_accessEv: symbol not found
Error relocating /usr/lib/libgpr.so.21: _ZNK4absl12lts_2021032411string_view4findEcm: symbol not found
Error relocating /usr/lib/libgpr.so.21: _ZNK4absl12lts_202103246Status14ForEachPayloadERKSt8functionIFvNS0_11string_viewERKNS0_4CordEEE: symbol not found
Error relocating /usr/lib/libgpr.so.21: _ZNK4absl12lts_2021032411string_view5rfindEcm: symbol not found
Error relocating /usr/lib/libgpr.so.21: _ZN4absl12lts_2021032416numbers_internal17safe_strto64_baseENS0_11string_viewEPli: symbol not found
Error relocating /usr/lib/libgpr.so.21: _ZN4absl12lts_202103244Cord10GetFlatAuxEPNS0_13cord_internal7CordRepEPNS0_11string_viewE: symbol not found
Error relocating /usr/lib/libgpr.so.21: _ZN4absl12lts_2021032419str_format_internal13FormatArgImpl8DispatchINS0_11string_viewEEEbNS2_4DataENS1_24FormatConversionSpecImplEPv: symbol not found
Error relocating /usr/lib/libgrpc.so.21: _ZN4absl12lts_2021032416BytesToHexStringB5cxx11ENS0_11string_viewE: symbol not found
Error relocating /usr/lib/libgrpc.so.21: _ZN4absl12lts_202103246StatusC1ENS0_10StatusCodeENS0_11string_viewE: symbol not found
Error relocating /usr/lib/libgrpc.so.21: _ZN4absl12lts_2021032416variant_internal21ThrowBadVariantAccessEv: symbol not found
Error relocating /usr/lib/libgrpc.so.21: _ZN4absl12lts_202103248ByStringC1ENS0_11string_viewE: symbol not found
Error relocating /usr/lib/libgrpc.so.21: _ZN4absl12lts_2021032410FormatTimeB5cxx11ENS0_11string_viewENS0_4TimeENS0_8TimeZoneE: symbol not found
Error relocating /usr/lib/libgrpc.so.21: _ZNK4absl12lts_2021032411string_view4findES1_m: symbol not found
Error relocating /usr/lib/libgrpc.so.21: _ZN4absl12lts_202103249CUnescapeENS0_11string_viewEPNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEES8_: symbol not found
Error relocating /usr/lib/libgrpc.so.21: _ZNK4absl12lts_2021032411string_view13find_first_ofES1_m: symbol not found
Error relocating /usr/lib/libgrpc.so.21: _ZN4absl12lts_2021032416numbers_internal17safe_strto64_baseENS0_11string_viewEPli: symbol not found
Error relocating /usr/lib/libgrpc.so.21: _ZNK4absl12lts_202103246ByChar4FindENS0_11string_viewEm: symbol not found
Error relocating /usr/lib/libgrpc.so.21: _ZN4absl12lts_2021032413NotFoundErrorENS0_11string_viewE: symbol not found
Error relocating /usr/lib/libgrpc.so.21: _ZN4absl12lts_2021032416numbers_internal18safe_strtou32_baseENS0_11string_viewEPji: symbol not found
Error relocating /usr/lib/libgrpc.so.21: _ZN4absl12lts_2021032416UnavailableErrorENS0_11string_viewE: symbol not found
Error relocating /usr/lib/libgrpc.so.21: _ZN4absl12lts_2021032418EndsWithIgnoreCaseENS0_11string_viewES1_: symbol not found
Error relocating /usr/lib/libgrpc.so.21: _ZN4absl12lts_2021032413InternalErrorENS0_11string_viewE: symbol not found
Error relocating /usr/lib/libgrpc.so.21: _ZN4absl12lts_2021032416strings_internal9CatPiecesB5cxx11ESt16initializer_listINS0_11string_viewEE: symbol not found
Error relocating /usr/lib/libgrpc.so.21: _ZNK4absl12lts_2021032411string_view5rfindEcm: symbol not found
Error relocating /usr/lib/libgrpc.so.21: _ZN4absl12lts_2021032413StrReplaceAllB5cxx11ENS0_11string_viewESt16initializer_listISt4pairIS1_S1_EE: symbol not found
Error relocating /usr/lib/libgrpc.so.21: _ZN4absl12lts_2021032416numbers_internal17safe_strto32_baseENS0_11string_viewEPii: symbol not found
Error relocating /usr/lib/libgrpc.so.21: _ZN4absl12lts_2021032418UnimplementedErrorENS0_11string_viewE: symbol not found
Error relocating /usr/lib/libgrpc.so.21: _ZN4absl12lts_2021032416EqualsIgnoreCaseENS0_11string_viewES1_: symbol not found
Error relocating /usr/lib/libgrpc.so.21: _ZN4absl12lts_2021032423FailedPreconditionErrorENS0_11string_viewE: symbol not found
Error relocating /usr/lib/libgrpc.so.21: _ZNK4absl12lts_2021032411string_view4findEcm: symbol not found
Error relocating /usr/lib/libgrpc.so.21: _ZNK4absl12lts_202103246Status10GetPayloadENS0_11string_viewE: symbol not found
Error relocating /usr/lib/libgrpc.so.21: _ZNK4absl12lts_202103248ByString4FindENS0_11string_viewEm: symbol not found
Error relocating /usr/lib/libgrpc.so.21: _ZNK4absl12lts_2021032411string_view5rfindES1_m: symbol not found
Error relocating /usr/lib/libgrpc.so.21: _ZN4absl12lts_202103249ParseTimeENS0_11string_viewES1_PNS0_4TimeEPNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEE: symbol not found
Error relocating /usr/lib/libgrpc.so.21: _ZN4absl12lts_2021032420StartsWithIgnoreCaseENS0_11string_viewES1_: symbol not found
Error relocating /usr/lib/libgrpc.so.21: _ZN4absl12lts_2021032420InvalidArgumentErrorENS0_11string_viewE: symbol not found
Error relocating /usr/lib/libgrpc.so.21: _ZN4absl12lts_202103246Status10SetPayloadENS0_11string_viewENS0_4CordE: symbol not found
Error relocating /usr/lib/libgrpc.so.21: _ZNK4absl12lts_2021032411string_view17find_first_not_ofES1_m: symbol not found
Error relocating /usr/lib/libgrpc.so.21: _ZN4absl12lts_2021032412Base64EscapeB5cxx11ENS0_11string_viewE: symbol not found
Error relocating /usr/lib/libgrpc.so.21: _ZN4absl12lts_2021032416numbers_internal18safe_strtou64_baseENS0_11string_viewEPmi: symbol not found
Error relocating /usr/lib/libgrpc.so.21: _ZN4absl12lts_2021032417optional_internal25throw_bad_optional_accessEv: symbol not found
Error relocating /usr/lib/libgrpc.so.21: _ZN4absl12lts_2021032419str_format_internal13FormatArgImpl8DispatchINS0_11string_viewEEEbNS2_4DataENS1_24FormatConversionSpecImplEPv: symbol not found

this is not caused by any specific abseil change- it worked fine prior to the recent rebuild for changing maintainer. it's probably related to gcc11, i remember seeing this a month ago when rebuilding it for other reasons.
looking at the symbol output of certain abseil .so's with nm shows that a lot of those are missing from them.
rebuilding with clang in the meantime fixes this- i have done so in 082830dc