Impossible to build a port libxml2 @2.10.3_1 because all compilers depend on this port.

[cave-canem]

I also tried to build libxml2 with 'clang-11-bootstrap @11.1.0_3' add the following lines to the Portfile:

  depends_build-append    port:clang-11-bootstrap
  configure.cc            ${prefix}/libexec/clang-11-bootstrap/bin/clang
  configure.cxx           ${prefix}/libexec/clang-11-bootstrap/bin/clang++

but it didn't work.

sudo port activate icu @72.1_0

port installed active and icu
The following ports are currently installed:
  icu @72.1_0 (active)

sudo port -vd upgrade -n --force libxml2
...

checking for gcc... /opt/MacPorts/libexec/clang-11-bootstrap/bin/clang
checking whether the C compiler works... no
configure: error: in `/opt/MacPorts/var/macports/build/_opt_macports-ports_textproc_libxml2/libxml2/work/libxml2-2.10.3':
configure: error: C compiler cannot create executables
See `config.log' for more details
Command failed:  cd "/opt/MacPorts/var/macports/build/_opt_macports-ports_textproc_libxml2/libxml2/work/libxml2-2.10.3" && ./configure --prefix=/opt/MacPorts --disable-silent-rules --enable-static --with-ftp --with-icu --without-python
Exit code: 77
Error: Failed to configure libxml2: consult /opt/MacPorts/var/macports/build/_opt_macports-ports_textproc_libxml2/libxml2/work/libxml2-2.10.3/config.log
Error: Failed to configure libxml2: configure failure: command execution failed
DEBUG: Error code: NONE
DEBUG: Backtrace: configure failure: command execution failed
    while executing
"$procedure $targetname"
Error: See /opt/MacPorts/var/macports/logs/_opt_macports-ports_textproc_libxml2/libxml2/main.log for details.
Error: Follow https://guide.macports.org/#project.tickets if you believe there is a bug.

But, although clang-11-bootstrap supposedly does not depend on libxml2, I see with my own eyes:

/opt/MacPorts/libexec/clang-11-bootstrap/bin/clang ./hello.c -o ./hello
dyld: Library not loaded: /opt/MacPorts/lib/libicui18n.67.dylib
  Referenced from: /opt/MacPorts/lib/libxml2.2.dylib
  Reason: image not found
clang-11: error: unable to execute command: Trace/BPT trap: 5
clang-11: error: linker command failed due to signal (use -v to see invocation)

[jmroot (Joshua Root)]

Why wouldn't it just build with the system clang?