How to get rid of CMake warnings on homebrew and readline

Help!
1

How to get rid of the following two CMake warnings seen during compiling from the git source ? They seem useless or wrong warnings for macOS users, though I am not familiar with cmake configuration.

-- Configuring SWI-Prolog-8.5.2
CMake Warning at cmake/port/Darwin.cmake:10 (message):
  Could not find Macport or Homebrew to provide dependencies 		 trying to
  configure with default search paths
Call Stack (most recent call first):
  cmake/Ports.cmake:2 (include)
  CMakeLists.txt:77 (include)

-- Found Readline: /opt/homebrew/opt/readline/include  
CMake Warning at packages/readline/CMakeLists.txt:16 (message):
  Found readline at /opt/homebrew/opt/readline/include, which

  	 looks like Apple readline.  We need GNU readline.  Dropping

  	 the readline interface
2

Seems it gets the detection of homebrew wrong? Check out cmake/port/Darwin.cmake on what it tries. I see there it expects brew in /usr/local. Is this outdated?

3

I have made a google search for “homebrew default directory /opt”. According one of the pages, now homebrew installs everything under
/opt/homebrew, not under /usr/local. I am still a little bit confused about this. BTW, where is cmake/port/Darwin.cmake ? I am curious of the contents, though I am not sure I can read it. Thanks for suggestion.

% /bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)"
Password:
==> This script will install:
/opt/homebrew/bin/brew
/opt/homebrew/share/doc/homebrew
/opt/homebrew/share/man/man1/brew.1
/opt/homebrew/share/zsh/site-functions/_brew
/opt/homebrew/etc/bash_completion.d/brew
/opt/homebrew
==> The following new directories will be created:
/opt/homebrew/bin
/opt/homebrew/etc
/opt/homebrew/include
/opt/homebrew/lib
/opt/homebrew/sbin
/opt/homebrew/share
/opt/homebrew/var
/opt/homebrew/opt
/opt/homebrew/share/zsh
/opt/homebrew/share/zsh/site-functions
/opt/homebrew/var/homebrew
/opt/homebrew/var/homebrew/linked
/opt/homebrew/Cellar
/opt/homebrew/Caskroom
/opt/homebrew/Frameworks
==> The Xcode Command Line Tools will be installed.

Press RETURN to continue or any other key to abort
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EDIT

A related google search gives me this codes, which seems related to my post. In fact, I see the warnings only when compiling on M1 Mac mini.

list(APPEND CMAKE_SYSTEM_PREFIX_PATH
  /sw        # Fink
  /opt/local # MacPorts
  /opt/homebrew # Brew on Apple Silicon
  )