boost-libs fails to build

Hello:
	On a system running:

FreeBSD 14.0-CURRENT #0 main-f0a15aafcb
Mon Oct 31 08:19:54 EDT 2022
amd64

	with all relevant ports up to date, boost-libs dies during
compilation with the errors appended.

	What vae I screwed up?
	More important: how do I fix it?


			Respectfully,


				Robert Huff


common.copy /data/port-work/usr/ports/devel/boost-libs/work/boost_1_81_0/stage/lib/libboost_wave.a

    cp "bin.v2/libs/wave/build/clang-linux-14/release/link-static/pch-off/threadapi-pthread/threading-multi/visibility-hidden/libboost_wave.a"  "/data/port-work/usr/ports/devel/boost-libs/work/boost_1_81_0/stage/lib/libboost_wave.a"

clang-linux.compile.c++ bin.v2/libs/url/build/clang-linux-14/release/link-static/pch-off/threading-multi/visibility-hidden/src.o

  "c++" -c -x c++ -fvisibility-inlines-hidden -m64 -pthread -O3 -Wall -fvisibility=hidden -Wno-inline -pipe -DLIBICONV_PLUG -fstack-protector-strong -fno-strict-aliasing -DLIBICONV_PLUG -std=gnu++17 -pipe -DLIBICONV_PLUG -fstack-protector-strong -fno-strict-aliasing -DBOOST_ALL_NO_LIB=1 -DBOOST_URL_SOURCE -DBOOST_URL_STATIC_LINK=1 -DNDEBUG -I"."   -o "bin.v2/libs/url/build/clang-linux-14/release/link-static/pch-off/threading-multi/visibility-hidden/src.o" "libs/url/src/src.cpp"

Assertion failed: (isa<X>(Val) && "cast<Ty>() argument of incompatible type!"), function cast, file /usr/src/contrib/llvm-project/llvm/include/llvm/Support/Casting.h, line 269.
PLEASE submit a bug report to https://bugs.freebsd.org/submit/ and include the crash backtrace, preprocessed source, and associated run script.
Stack dump:
0.	Program arguments: /usr/bin/c++ -fvisibility-inlines-hidden -m64 -pthread -O3 -Wall -fvisibility=hidden -Wno-inline -pipe -fstack-protector-strong -fno-strict-aliasing -std=gnu++17 -pipe -fstack-protector-strong -fno-strict-aliasing -DLIBICONV_PLUG -DLIBICONV_PLUG -DLIBICONV_PLUG -DBOOST_ALL_NO_LIB=1 -DBOOST_URL_SOURCE -DBOOST_URL_STATIC_LINK=1 -DNDEBUG -I. -x c++ -c -o bin.v2/libs/url/build/clang-linux-14/release/link-static/pch-off/threading-multi/visibility-hidden/src.o libs/url/src/src.cpp
1.	./boost/url/impl/segments_view.ipp:33:1: current parser token '{'
2.	./boost/url/impl/segments_view.ipp:17:1: parsing namespace 'boost'
3.	./boost/url/impl/segments_view.ipp:18:1: parsing namespace 'boost::urls'
 #0 0x00000000050b98a1 (/usr/bin/c+++0x50b98a1)
 #1 0x00000000050b7bd5 (/usr/bin/c+++0x50b7bd5)
 #2 0x000000000505fdfe (/usr/bin/c+++0x505fdfe)
 #3 0x000000000505ffc3 (/usr/bin/c+++0x505ffc3)
 #4 0x000000082b1a5a60 (/lib/libthr.so.3+0x19a60)
 #5 0x000000082b1a501f (/lib/libthr.so.3+0x1901f)
 #6 0x00000008279e6853 ([vdso]+0x2d3)
 #7 0x000000082d8672ea __sys_thr_kill (/lib/libc.so.7+0x13d2ea)
 #8 0x000000082d7e0064 __raise (/lib/libc.so.7+0xb6064)
 #9 0x000000082d891159 abort (/lib/libc.so.7+0x167159)
#10 0x000000082d7c2e41 (/lib/libc.so.7+0x98e41)
#11 0x00000000038b364b (/usr/bin/c+++0x38b364b)
#12 0x00000000038b2e19 (/usr/bin/c+++0x38b2e19)
#13 0x00000000038b19cc (/usr/bin/c+++0x38b19cc)
#14 0x00000000038b201d (/usr/bin/c+++0x38b201d)
#15 0x000000000356342c (/usr/bin/c+++0x356342c)
#16 0x00000000035628cb (/usr/bin/c+++0x35628cb)
#17 0x00000000034ec7a8 (/usr/bin/c+++0x34ec7a8)
#18 0x000000000353d4a8 (/usr/bin/c+++0x353d4a8)
#19 0x00000000034eb842 (/usr/bin/c+++0x34eb842)
#20 0x00000000034eb2d5 (/usr/bin/c+++0x34eb2d5)
#21 0x00000000034ea1f8 (/usr/bin/c+++0x34ea1f8)
#22 0x0000000003551bb4 (/usr/bin/c+++0x3551bb4)
#23 0x000000000355142d (/usr/bin/c+++0x355142d)
#24 0x0000000003536c90 (/usr/bin/c+++0x3536c90)
#25 0x00000000034e9eec (/usr/bin/c+++0x34e9eec)
#26 0x0000000003551bb4 (/usr/bin/c+++0x3551bb4)
#27 0x000000000355142d (/usr/bin/c+++0x355142d)
#28 0x0000000003536c90 (/usr/bin/c+++0x3536c90)
#29 0x00000000034e9eec (/usr/bin/c+++0x34e9eec)
#30 0x00000000034e85b0 (/usr/bin/c+++0x34e85b0)
#31 0x00000000034e2bed (/usr/bin/c+++0x34e2bed)
#32 0x0000000002ee99df (/usr/bin/c+++0x2ee99df)
#33 0x0000000002e7e01f (/usr/bin/c+++0x2e7e01f)
#34 0x0000000002fa6a86 (/usr/bin/c+++0x2fa6a86)
#35 0x0000000002477b65 (/usr/bin/c+++0x2477b65)
#36 0x00000000024850b5 (/usr/bin/c+++0x24850b5)
#37 0x0000000002d3a187 (/usr/bin/c+++0x2d3a187)
#38 0x000000000505fd34 (/usr/bin/c+++0x505fd34)
#39 0x0000000002d39d93 (/usr/bin/c+++0x2d39d93)
#40 0x0000000002d081b2 (/usr/bin/c+++0x2d081b2)
#41 0x0000000002d08659 (/usr/bin/c+++0x2d08659)
#42 0x0000000002d1d37c (/usr/bin/c+++0x2d1d37c)
c++: error: clang frontend command failed with exit code 134 (use -v to see invocation)
FreeBSD clang version 14.0.5 (https://github.com/llvm/llvm-project.git llvmorg-14.0.5-0-gc12386ae247c)
Target: x86_64-unknown-freebsd14.0
Thread model: posix
InstalledDir: /usr/bin
c++: note: diagnostic msg: 
********************

PLEASE ATTACH THE FOLLOWING FILES TO THE BUG REPORT:
Preprocessed source(s) and associated run script(s) are located at:
c++: note: diagnostic msg: /tmp/src-024ebe.cpp
c++: note: diagnostic msg: /tmp/src-024ebe.sh
c++: note: diagnostic msg: 

********************
...failed clang-linux.compile.c++ bin.v2/libs/url/build/clang-linux-14/release/link-static/pch-off/threading-multi/visibility-hidden/src.o...
...skipped <pbin.v2/libs/url/build/clang-linux-14/release/link-static/pch-off/threading-multi/visibility-hidden>libboost_url.a(clean) for lack of <pbin.v2/libs/url/build/clang-linux-14/release/link-static/pch-off/threading-multi/visibility-hidden>src.o...
...skipped <pbin.v2/libs/url/build/clang-linux-14/release/link-static/pch-off/threading-multi/visibility-hidden>libboost_url.a for lack of <pbin.v2/libs/url/build/clang-linux-14/release/link-static/pch-off/threading-multi/visibility-hidden>src.o...
...skipped <p/data/port-work/usr/ports/devel/boost-libs/work/boost_1_81_0/stage/lib>libboost_url.a for lack of <pbin.v2/libs/url/build/clang-linux-14/release/link-static/pch-off/threading-multi/visibility-hidden>libboost_url.a...
...skipped <pbin.v2/libs/url/build/clang-linux-14/release/link-static/pch-off/threading-multi/visibility-hidden>libboost_url-variant-static.cmake for lack of <pbin.v2/libs/url/build/clang-linux-14/release/link-static/pch-off/threading-multi/visibility-hidden>libboost_url.a...
...skipped <p/data/port-work/usr/ports/devel/boost-libs/work/boost_1_81_0/stage/lib/cmake/boost_url-1.81.0>libboost_url-variant-static.cmake for lack of <pbin.v2/libs/url/build/clang-linux-14/release/link-static/pch-off/threading-multi/visibility-hidden>libboost_url-variant-static.cmake...
...failed updating 2 targets...
...skipped 12 targets...
...updated 1764 targets...
*** Error code 1

Stop.
make[1]: stopped in /usr/ports/devel/boost-libs
*** Error code 1

Stop.
make: stopped in /usr/ports/devel/boost-libs