brew/Library/Homebrew/extend/os/linux/linkage_checker.rb

# typed: true # rubocop:todo Sorbet/StrictSigil
# frozen_string_literal: true

require "compilers"

module OS
  module Linux
    module LinkageChecker
      # Libraries provided by glibc and gcc.
      SYSTEM_LIBRARY_ALLOWLIST = %w[
        ld-linux-x86-64.so.2
        ld-linux-aarch64.so.1
        libanl.so.1
        libatomic.so.1
        libc.so.6
        libdl.so.2
        libm.so.6
        libmvec.so.1
        libnss_files.so.2
        libpthread.so.0
        libresolv.so.2
        librt.so.1
        libthread_db.so.1
        libutil.so.1
        libgcc_s.so.1
        libgomp.so.1
        libstdc++.so.6
        libquadmath.so.0
      ].freeze

      private

      def check_dylibs(rebuild_cache:)
        super

        # glibc and gcc are implicit dependencies.
        # No other linkage to system libraries is expected or desired.
        @unwanted_system_dylibs = @system_dylibs.reject do |s|
          SYSTEM_LIBRARY_ALLOWLIST.include? File.basename(s)
        end

        # We build all formulae with an RPATH that includes the gcc formula's runtime lib directory.
        # See: https://github.com/Homebrew/brew/blob/e689cc07/Library/Homebrew/extend/os/linux/extend/ENV/super.rb#L53
        # This results in formulae showing linkage with gcc whenever it is installed, even if no dependency is
        # declared.
        # See discussions at:
        #   https://github.com/Homebrew/brew/pull/13659
        #   https://github.com/Homebrew/brew/pull/13796
        # TODO: Find a nicer way to handle this. (e.g. examining the ELF file to determine the required libstdc++.)
        @undeclared_deps.delete("gcc")
        @indirect_deps.delete("gcc")
      end
    end
  end
end

LinkageChecker.prepend(OS::Linux::LinkageChecker)