Avoid passing around a massive $LOAD_PATH.

Portable Ruby crashes if the $LOAD_PATH gets too big.

Library/Homebrew/build.rb

@@ -6,7 +6,7 @@
 
 old_trap = trap("INT") { exit! 130 }
 
-require "global"
+require_relative "global"
 require "build_options"
 require "cxxstdlib"
 require "keg"

Library/Homebrew/config.rb

@@ -67,3 +67,9 @@ HOMEBREW_TEMP = Pathname(EnvVar["HOMEBREW_TEMP"]).yield_self do |tmp|
   tmp.mkpath unless tmp.exist?
   tmp.realpath
 end.freeze
+
+# The Ruby path and args to use for forked Ruby calls
+HOMEBREW_RUBY_EXEC_ARGS = [
+  RUBY_PATH,
+  ENV["HOMEBREW_RUBY_WARNINGS"],
+].freeze

Library/Homebrew/dev-cmd/test.rb

@@ -77,10 +77,7 @@ module Homebrew
       env = ENV.to_hash
 
       begin
-        exec_args = %W[
-          #{RUBY_PATH}
-          #{ENV["HOMEBREW_RUBY_WARNINGS"]}
-          -I #{$LOAD_PATH.join(File::PATH_SEPARATOR)}
+        exec_args = HOMEBREW_RUBY_EXEC_ARGS + %W[
           --
           #{HOMEBREW_LIBRARY_PATH}/test.rb
           #{f.path}

Library/Homebrew/formula_info.rb

@@ -16,13 +16,11 @@ class FormulaInfo
   # Returns nil if formula is absent or if there was an error reading it.
   def self.lookup(name)
     json = Utils.popen_read(
-      RUBY_PATH,
-      ENV["HOMEBREW_RUBY_WARNINGS"],
-      "-I", $LOAD_PATH.join(File::PATH_SEPARATOR),
+      *HOMEBREW_RUBY_EXEC_ARGS,
       HOMEBREW_LIBRARY_PATH/"brew.rb",
       "info",
       "--json=v1",
-      name
+      name,
     )
 
     return unless $CHILD_STATUS.success?

Library/Homebrew/formula_installer.rb

@@ -896,13 +896,12 @@ class FormulaInstaller
     # 1. formulae can modify ENV, so we must ensure that each
     #    installation has a pristine ENV when it starts, forking now is
     #    the easiest way to do this
-    args = %W[
-      nice #{RUBY_PATH}
-      #{ENV["HOMEBREW_RUBY_WARNINGS"]}
-      -I #{$LOAD_PATH.join(File::PATH_SEPARATOR)}
-      --
-      #{HOMEBREW_LIBRARY_PATH}/build.rb
-      #{formula.specified_path}
+    args = [
+      "nice",
+      *HOMEBREW_RUBY_EXEC_ARGS,
+      "--",
+      HOMEBREW_LIBRARY_PATH/"build.rb",
+      formula.specified_path,
     ].concat(build_argv)
 
     Utils.safe_fork do

Library/Homebrew/postinstall.rb

@@ -3,7 +3,7 @@
 
 old_trap = trap("INT") { exit! 130 }
 
-require "global"
+require_relative "global"
 require "debrew"
 require "fcntl"
 require "socket"

Library/Homebrew/software_spec.rb

@@ -11,7 +11,6 @@ require "dependency_collector"
 require "utils/bottles"
 require "patch"
 require "compilers"
-require "global"
 require "os/mac/version"
 require "extend/on_os"
 

Library/Homebrew/test.rb

@@ -3,7 +3,7 @@
 
 old_trap = trap("INT") { exit! 130 }
 
-require "global"
+require_relative "global"
 require "extend/ENV"
 require "timeout"
 require "debrew"

Library/Homebrew/test/dev-cmd/test_spec.rb

@@ -6,8 +6,7 @@ require "cmd/shared_examples/args_parse"
 describe "brew test" do
   it_behaves_like "parseable arguments"
 
-  # randomly segfaults on Linux with portable-ruby.
-  it "tests a given Formula", :integration_test, :needs_macos do
+  it "tests a given Formula", :integration_test do
     install_test_formula "testball", <<~'RUBY'
       test do
         assert_equal "test", shell_output("#{bin}/test")

Library/Homebrew/test/formula_info_spec.rb

@@ -2,7 +2,6 @@
 # frozen_string_literal: true
 
 require "formula_info"
-require "global"
 
 describe FormulaInfo, :integration_test do
   it "tests the FormulaInfo class" do

Library/Homebrew/test/support/helper/spec/shared_context/integration_test.rb

@@ -87,10 +87,7 @@ RSpec.shared_context "integration test" do # rubocop:disable RSpec/ContextWordin
     )
 
     @ruby_args ||= begin
-      ruby_args = [
-        ENV["HOMEBREW_RUBY_WARNINGS"],
-        "-I", $LOAD_PATH.join(File::PATH_SEPARATOR)
-      ]
+      ruby_args = HOMEBREW_RUBY_EXEC_ARGS.dup
       if ENV["HOMEBREW_TESTS_COVERAGE"]
         simplecov_spec = Gem.loaded_specs["simplecov"]
         specs = [simplecov_spec]
@@ -111,12 +108,12 @@ RSpec.shared_context "integration test" do # rubocop:disable RSpec/ContextWordin
         libs.each { |lib| ruby_args << "-I" << lib }
         ruby_args << "-rsimplecov"
       end
-      ruby_args << "-rtest/support/helper/integration_mocks"
+      ruby_args << "-r#{HOMEBREW_LIBRARY_PATH}/test/support/helper/integration_mocks"
       ruby_args << (HOMEBREW_LIBRARY_PATH/"brew.rb").resolved_path.to_s
     end
 
     Bundler.with_clean_env do
-      stdout, stderr, status = Open3.capture3(env, RUBY_PATH, *@ruby_args, *args)
+      stdout, stderr, status = Open3.capture3(env, *@ruby_args, *args)
       $stdout.print stdout
       $stderr.print stderr
       status

Library/Homebrew/test/support/lib/config.rb

@@ -37,6 +37,11 @@ HOMEBREW_LOCKS         = (HOMEBREW_PREFIX.parent/"locks").freeze
 HOMEBREW_CELLAR        = (HOMEBREW_PREFIX.parent/"cellar").freeze
 HOMEBREW_LOGS          = (HOMEBREW_PREFIX.parent/"logs").freeze
 HOMEBREW_TEMP          = (HOMEBREW_PREFIX.parent/"temp").freeze
+HOMEBREW_RUBY_EXEC_ARGS = [
+  RUBY_PATH,
+  ENV["HOMEBREW_RUBY_WARNINGS"],
+  "-I", HOMEBREW_LIBRARY_PATH/"test/support/lib"
+].freeze
 
 TEST_FIXTURE_DIR = (HOMEBREW_LIBRARY_PATH/"test/support/fixtures").freeze