Can't build boost on FreeBSD

Trying to build boost from master on FreeBSD 12.4. But failed so far.

System info:

```sh
$ uname -mrs
FreeBSD 12.4-RELEASE i386
# dmesg | grep CPU
CPU: Intel(R) Core(TM) i3 CPU M 330 @ 2.13GHz (2128.05-MHz 686-class CPU)
FreeBSD/SMP: Multiprocessor System Detected: 4 CPUs
cpu0: on acpi0
# dmesg | grep memory.*=
real memory = 4294967296 (4096 MB)
avail memory = 3048796160 (2907 MB)]
$ echo $SHELL
/usr/local/bin/bash
```

Preparing:

```sh
$ sudo pkg install -y gcc11 python boost-build
$ python --version
Python 3.9.18
$ b2 --version
B2 4.9-git

$ gcc11 --version
gcc11 (FreeBSD Ports Collection) 11.3.0
Copyright (C) 2021 Free Software Foundation, Inc.
This is free software; see the source for copying conditions. There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

$ grep -q '^using gcc : boost ' /etc/site-config.jam || ( sudo touch /etc/site-config.jam && echo 'using gcc : boost : g++11 : -Wl,-rpath=/usr/local/lib/gcc11 -std=c++14 ;' | sudo tee -a /etc/site-config.jam )
$ git clone --depth 1 https://github.com/boostorg/boost && cd boost
$ git submodule update --init --recursive
$ git log --oneline
be1e29c (grafted, HEAD -> master, origin/master, origin/HEAD) Update core from master
$ ./bootstrap.sh
```

Building:

```sh
$ b2 gcc-boost 2>&1 | tee b2.log
```

Ends with something like:

```
...
common.copy /path/to/repos/boost/stage/lib/libboost_wave.a
...failed updating 252 targets...
...skipped 60 targets...
...updated 2153 targets...
```

Tried with gcc13 (13.1.0) too and the results are similar.

[b2-gcc11.log](https://github.com/boostorg/boost/files/12839419/b2-gcc11.log)
[b2-gcc13.log](https://github.com/boostorg/boost/files/12839420/b2-gcc13.log)

Tried applying patches from [FreeBSD port](https://github.com/freebsd/freebsd-ports/tree/main/devel/boost-libs/files) but didn't work either.