diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 892ec5041de7..b955ae7c1c5e 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -192,7 +192,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        ruby: [2.6, 2.7, '3.0']
+        ruby: [2.7, '3.0', 3.1]
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v2
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 7fa2d641c1c9..8677be2ab050 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -11,6 +11,8 @@ Bug fixes:
 * Fix capacity computation for huge `Hash` (#2635, @eregon).
 * Fix aliased methods to return the correct owner when method is from a superclass (@bjfish).
 * Fix `String#[Regexp, Integer]` when the capture group exists but is not matched (@eregon).
+* Fix `File.open` mode string parsing when binary option is the third character (@bjfish).
+* Fix `rb_scan_args_kw` macro to avoid shadowing variables (#2649, @aardvark179).
 
 Compatibility:
 
@@ -22,6 +24,8 @@ Compatibility:
 * Implement `rb_gc_mark_maybe` and `rb_global_variable` to ensure `VALUE` stay live in C extensions (@aardvark179).
 * Implement `rb_imemo_tmpbuf` allocation for `ripper` (@aardvark179).
 * `Process.euid=` should accept String (#2615, @ngtban).
+* Implement `inherit` argument for `Module#class_variables` (#2653, @bjfish).
+* Fix `Float#/` when dividing by `Rational` (@bjfish).
 
 Performance:
 
diff --git a/bench/benchmark-interface/examples/error.rb b/bench/benchmark-interface/examples/error.rb
index dcc135c83263..9b55c36455e0 100644
--- a/bench/benchmark-interface/examples/error.rb
+++ b/bench/benchmark-interface/examples/error.rb
@@ -6,8 +6,8 @@
 # GNU General Public License version 2, or
 # GNU Lesser General Public License version 2.1.
 
-start = Time.now
+start = BenchmarkInterface.get_time
 
 benchmark do
-  1/0 if Time.now - start > 3
+  1/0 if BenchmarkInterface.get_time - start > 3
 end
diff --git a/bench/benchmark-interface/lib/benchmark-interface.rb b/bench/benchmark-interface/lib/benchmark-interface.rb
index 9762a2e91b30..fe2488da4924 100644
--- a/bench/benchmark-interface/lib/benchmark-interface.rb
+++ b/bench/benchmark-interface/lib/benchmark-interface.rb
@@ -7,7 +7,9 @@
 # GNU Lesser General Public License version 2.1.
 
 require 'benchmark-interface/version'
+require 'benchmark-interface/timing'
 require 'benchmark-interface/benchmark'
+require 'benchmark-interface/benchmark-api'
 require 'benchmark-interface/benchmark-set'
 require 'benchmark-interface/frontends/mri'
 require 'benchmark-interface/backends/simple'
@@ -21,6 +23,8 @@
 require 'benchmark-interface/run'
 
 module BenchmarkInterface
+  extend Timing
+
   def self.benchmark(name=nil, &block)
     BenchmarkInterface::BenchmarkSet.current.register name, block
   end
@@ -28,9 +32,10 @@ def self.benchmark(name=nil, &block)
   def self.run_n_iterations(iterations)
     i = 0
     while i < iterations
-      yield
+      result = yield
       i += 1
     end
+    result
   end
 end
 
@@ -38,7 +43,7 @@ def benchmark(name=nil, &block)
   BenchmarkInterface.benchmark name, &block
 end
 
-if $PROGRAM_NAME.split('/').last != 'benchmark'
+if File.basename($PROGRAM_NAME) != 'benchmark'
   set = BenchmarkInterface::BenchmarkSet.new
   backend = BenchmarkInterface::Backends::Bips
 
diff --git a/bench/benchmark-interface/lib/benchmark-interface/backends/simple.rb b/bench/benchmark-interface/lib/benchmark-interface/backends/simple.rb
index 96688a5f275f..49c5bf43884b 100644
--- a/bench/benchmark-interface/lib/benchmark-interface/backends/simple.rb
+++ b/bench/benchmark-interface/lib/benchmark-interface/backends/simple.rb
@@ -9,22 +9,11 @@
 module BenchmarkInterface
   module Backends
     module Simple
-      
+      extend BenchmarkInterface::Timing
+
       INITIAL_ITERATIONS = 1
       MAX_ITERATIONS = 2147483647
 
-      # Accomodates Rubinius
-      
-      if defined?(Process::CLOCK_MONOTONIC)
-        def self.get_time
-          Process.clock_gettime(Process::CLOCK_MONOTONIC)
-        end
-      else
-        def self.get_time
-          Time.now
-        end
-      end
-
       def self.run(benchmark_set, names, options)
         full_time = options['--time']
         freq = options['--freq']
@@ -42,8 +31,9 @@ def self.run(benchmark_set, names, options)
 
           while get_time - start_time < full_time
             start_round_time = get_time
-            BenchmarkInterface.run_n_iterations(iterations, &block)
+            result = BenchmarkInterface.run_n_iterations(iterations, &block)
             round_time = get_time - start_round_time
+            benchmark.verify!(result)
             
             # If the round time was very low and so very imprecise then we may
             # get a wild number of iterations next time.
diff --git a/bench/benchmark-interface/lib/benchmark-interface/backends/stable.rb b/bench/benchmark-interface/lib/benchmark-interface/backends/stable.rb
index 57a06f52571d..b7993229d20f 100644
--- a/bench/benchmark-interface/lib/benchmark-interface/backends/stable.rb
+++ b/bench/benchmark-interface/lib/benchmark-interface/backends/stable.rb
@@ -9,6 +9,7 @@
 module BenchmarkInterface
   module Backends
     module Stable
+      extend BenchmarkInterface::Timing
 
       def self.run(benchmark_set, names, options)
         full_time = options['--time']
@@ -22,16 +23,16 @@ def self.run(benchmark_set, names, options)
           puts benchmark.name
           block = benchmark.block
 
-          start_time = Time.now
+          start_time = get_time
 
-          while Time.now - start_time < full_time
-            start_round_time = Time.now
+          while get_time - start_time < full_time
+            start_round_time = get_time
             block.call
-            round_time = Time.now - start_round_time
+            round_time = get_time - start_round_time
             
             ips = 1 / round_time
             puts 1 if print_iterations
-            puts Time.now - start_time if elapsed
+            puts get_time - start_time if elapsed
             puts ips * inner_iterations
           end
         end
diff --git a/bench/benchmark-interface/lib/benchmark-interface/benchmark-api.rb b/bench/benchmark-interface/lib/benchmark-interface/benchmark-api.rb
new file mode 100644
index 000000000000..0318ddfe5f25
--- /dev/null
+++ b/bench/benchmark-interface/lib/benchmark-interface/benchmark-api.rb
@@ -0,0 +1,21 @@
+# Copyright (c) 2022 Oracle and/or its affiliates. All rights reserved. This
+# code is released under a tri EPL/GPL/LGPL license. You can use it,
+# redistribute it and/or modify it under the terms of the:
+#
+# Eclipse Public License version 2.0, or
+# GNU General Public License version 2, or
+# GNU Lesser General Public License version 2.1.
+
+module BenchmarkInterface
+  class BenchmarkAPI
+    attr_reader :benchmark
+
+    def initialize(benchmark)
+      @benchmark = benchmark
+    end
+
+    def verify(&block)
+      @benchmark.verify_block = block
+    end
+  end
+end
diff --git a/bench/benchmark-interface/lib/benchmark-interface/benchmark-set.rb b/bench/benchmark-interface/lib/benchmark-interface/benchmark-set.rb
index da683a997708..05eb21b85f1e 100644
--- a/bench/benchmark-interface/lib/benchmark-interface/benchmark-set.rb
+++ b/bench/benchmark-interface/lib/benchmark-interface/benchmark-set.rb
@@ -35,7 +35,9 @@ def load_mri_benchmarks(path, options)
 
     def register(name, code)
       name = implicit_name unless name
-      @benchmarks.push Benchmark.new(name, code)
+      benchmark = Benchmark.new(name, code)
+      @benchmarks.push benchmark
+      BenchmarkInterface::BenchmarkAPI.new(benchmark)
     end
 
     def implicit_name
diff --git a/bench/benchmark-interface/lib/benchmark-interface/benchmark.rb b/bench/benchmark-interface/lib/benchmark-interface/benchmark.rb
index 32d72b1e3ef8..0e197d2eddda 100644
--- a/bench/benchmark-interface/lib/benchmark-interface/benchmark.rb
+++ b/bench/benchmark-interface/lib/benchmark-interface/benchmark.rb
@@ -10,12 +10,23 @@ module BenchmarkInterface
   class Benchmark
   
     attr_reader :name, :block
-  
+    attr_writer :verify_block
+
     def initialize(name, block)
       @name = name
       @block = block
     end
 
+    def verify!(result)
+      if @verify_block
+        check = @verify_block.call(result)
+        unless check
+          raise "Benchmark #{@name} did not return the correct value, " \
+            "the verify block returned #{check.inspect} and the result was:\n#{result.inspect}"
+        end
+      end
+    end
+
     def remove_line_numbers
       @name = @name.split(':')[0...-1].join(':') if @name.include? ':'
     end
@@ -23,18 +34,21 @@ def remove_line_numbers
     def time_block(desired_time)
       iterations = 1
       while true
-        start = Time.now
+        start = BenchmarkInterface.get_time
         if block.arity == 1
-          block.call iterations
+          result = block.call iterations
         else
-          BenchmarkInterface.run_n_iterations(iterations, &block)
+          result = BenchmarkInterface.run_n_iterations(iterations, &block)
         end
+        time = BenchmarkInterface.get_time - start
+
+        verify!(result)
 
-        time = Time.now - start
         return [time, iterations] if time >= desired_time
         iterations *= 2
       end
     end
+    private :time_block
 
     def basic_iteration_time
       time, iterations = time_block(0.1)
diff --git a/bench/benchmark-interface/lib/benchmark-interface/timing.rb b/bench/benchmark-interface/lib/benchmark-interface/timing.rb
new file mode 100644
index 000000000000..f41354f31105
--- /dev/null
+++ b/bench/benchmark-interface/lib/benchmark-interface/timing.rb
@@ -0,0 +1,22 @@
+# Copyright (c) 2022 Oracle and/or its affiliates. All rights reserved. This
+# code is released under a tri EPL/GPL/LGPL license. You can use it,
+# redistribute it and/or modify it under the terms of the:
+#
+# Eclipse Public License version 2.0, or
+# GNU General Public License version 2, or
+# GNU Lesser General Public License version 2.1.
+
+module BenchmarkInterface
+  module Timing
+    if defined?(Process::CLOCK_MONOTONIC)
+      def get_time
+        Process.clock_gettime(Process::CLOCK_MONOTONIC)
+      end
+    else
+      # Accomodates Rubinius
+      def get_time
+        Time.now
+      end
+    end
+  end
+end
diff --git a/bench/liquid/liquid-bibs-render.rb b/bench/liquid/liquid-bibs-render.rb
index 29d49af078ce..49e7275e9d9e 100644
--- a/bench/liquid/liquid-bibs-render.rb
+++ b/bench/liquid/liquid-bibs-render.rb
@@ -13,5 +13,7 @@
 benchmark do
   result = template.render!(data)
   dev_null.write result
-  raise StandardError, "Incorrect rendering result" unless result == expected_result
+  result
+end.verify do |result|
+  result == expected_result
 end
diff --git a/ci.jsonnet b/ci.jsonnet
index af26f7a01e3f..029495d15258 100644
--- a/ci.jsonnet
+++ b/ci.jsonnet
@@ -10,7 +10,7 @@
 # https://github.com/google/jsonnet/releases and compiled.
 
 # CONFIGURATION
-local overlay = "ffb092a26e86b0b4c2ac33bdbc329d938b527942";
+local overlay = "52900f1ecd0b7b23e0bbb74e7552886e6ec29df3";
 
 # For debugging: generated builds will be restricted to those listed in
 # the array. No restriction is applied when it is empty.
@@ -34,6 +34,8 @@ local part_definitions = {
 
   use: {
     common: {
+      python_version: "3", # To use the correct virtualenv
+
       environment+: {
         path+:: [],
         TRUFFLERUBY_CI: "true",
@@ -676,19 +678,6 @@ local composition_environment = utils.add_inclusion_tracking(part_definitions, "
       "ruby-benchmarks-other-svm-graal-enterprise-multi-tier": shared + svm_other + svm_configurations["svm-graal-enterprise"] + $.use.multi_tier,
     } +
 
-    {
-      local shared = $.platform.linux + $.jdk.v11 + $.use.common + $.use.gem_test_pack +
-                     $.benchmark.runner + $.benchmark.server +
-                     { timelimit: "00:30:00" },
-
-      "ruby-benchmarks-server-mri": shared + other_rubies.mri,
-      "ruby-benchmarks-server-jruby": shared + other_rubies.jruby,
-      "ruby-benchmarks-server-graal-core": shared + graal_configurations["graal-core"] + $.use.no_multi_tier,
-      "ruby-benchmarks-server-graal-core-multi-tier": shared + graal_configurations["graal-core"] + $.use.multi_tier,
-      "ruby-benchmarks-server-graal-enterprise": shared + graal_configurations["graal-enterprise"] + $.use.no_multi_tier,
-      "ruby-benchmarks-server-graal-enterprise-multi-tier": shared + graal_configurations["graal-enterprise"] + $.use.multi_tier,
-    } +
-
     {
       "ruby-metrics-truffle":
         $.platform.linux + $.jdk.v11 + $.use.common + $.env.jvm + $.use.build +
@@ -735,6 +724,7 @@ local composition_environment = utils.add_inclusion_tracking(part_definitions, "
 };
 
 {
+  part_definitions:: part_definitions,
   specVersion: "3",
   overlay: overlay,
   builds: composition_environment.builds,
diff --git a/common.json b/common.json
index bc1ca838a9c9..6b5da58c00f0 100644
--- a/common.json
+++ b/common.json
@@ -30,23 +30,18 @@
   ],
 
   "deps": {
-    "COMMENT.common": [
-      "pip:isort is a dependency of pip:pylint. The explicit dependency on the pip package works around",
-      "https://bugzilla.redhat.com/show_bug.cgi?id=1710221 on older Redhat-based systems, and doesn't",
-      "hurt on others."
-    ],
     "common": {
       "timelimit": "30:00",
       "environment": {
-        "MX_PYTHON": "python3"
+        "MX_PYTHON": "python3.8"
       },
       "packages": {
-        "pip:isort": "==4.3.19",
-        "pip:logilab-common": "==1.4.4",
-        "pip:pylint": "==1.9.3",
+        "python3": "==3.8.10",
+        "pip:pylint": "==2.4.4",
         "pip:lazy-object-proxy": "==1.6.0",
         "pip:ninja_syntax": "==1.7.2"
-      }
+      },
+      "python_version": "3"
     },
 
     "linux": {
@@ -80,6 +75,15 @@
       },
       "environment": {
         "ECLIPSE_EXE": "$ECLIPSE/eclipse"
+      },
+
+      "COMMENT.eclipse_org": [
+        "Coordinates for downloading same version as above directly from eclipse.org (used by GitHub actions).",
+        "Template URL: https://archive.eclipse.org/eclipse/downloads/drops4/R-<eclipse_org.version>-<eclipse_org.timestamp>/eclipse-SDK-<eclipse_org.version>-linux-gtk-x86_64.tar.gz"
+      ],
+      "eclipse_org": {
+        "version": "4.14",
+        "timestamp": "201912100610"
       }
     },
     "jdt": {
diff --git a/lib/cext/ABI_version.txt b/lib/cext/ABI_version.txt
index 00750edc07d6..b8626c4cff28 100644
--- a/lib/cext/ABI_version.txt
+++ b/lib/cext/ABI_version.txt
@@ -1 +1 @@
-3
+4
diff --git a/lib/cext/include/truffleruby/truffleruby.h b/lib/cext/include/truffleruby/truffleruby.h
index d63b7c25facf..7ec070e5d951 100644
--- a/lib/cext/include/truffleruby/truffleruby.h
+++ b/lib/cext/include/truffleruby/truffleruby.h
@@ -61,21 +61,25 @@ if (polyglot_as_boolean(polyglot_invoke(RUBY_CEXT, "warning?"))) { \
 } \
 })
 
+struct rb_tr_scan_args_parse_data {
+  int pre;
+  int optional;
+  bool rest;
+  int post;
+  bool kwargs;
+  bool block;
+};
+
 #define rb_tr_scan_args_kw(kw_flag, argc, argv, format, v1, v2, v3, v4, v5, v6, v7, v8, v9, v10) \
   (RBIMPL_CONSTANT_P(format) ?                                             \
      __extension__ ({ \
-         static bool evaled; \
-         static int pre; \
-         static int optional; \
-         static bool rest; \
-         static int post; \
-         static bool kwargs; \
-         static bool block; \
-         if (!evaled) { \
-             rb_tr_scan_args_kw_parse(format, &pre, &optional, &rest, &post, &kwargs, &block); \
-             evaled = true; \
+         static bool rb_tr_scan_args_format_str_evaled; \
+         static struct rb_tr_scan_args_parse_data rb_tr_scan_data; \
+         if (!rb_tr_scan_args_format_str_evaled) { \
+             rb_tr_scan_args_kw_parse(format, &rb_tr_scan_data); \
+             rb_tr_scan_args_format_str_evaled = true; \
          } \
-         rb_tr_scan_args_kw_int(kw_flag, argc, argv, pre, optional, rest, post, kwargs, block, v1, v2, v3, v4, v5, v6, v7, v8, v9, v10); \
+         rb_tr_scan_args_kw_int(kw_flag, argc, argv, rb_tr_scan_data, v1, v2, v3, v4, v5, v6, v7, v8, v9, v10); \
      }) : \
   rb_tr_scan_args_kw_non_const(kw_flag, argc, argv, format, v1, v2, v3, v4, v5, v6, v7, v8, v9, v10))
 
@@ -214,10 +218,10 @@ static inline char *rb_tr_string_value_cstr(VALUE *value_pointer) {
   return RSTRING_PTR(string);
 }
 
-void rb_tr_scan_args_kw_parse(const char *format, int *pre, int *optional, bool *rest, int *post, bool *kwargs, bool *block);
+void rb_tr_scan_args_kw_parse(const char *format, struct rb_tr_scan_args_parse_data *parse_data);
 
-ALWAYS_INLINE(static int rb_tr_scan_args_kw_int(int kw_flag, int argc, VALUE *argv, int pre, int optional, bool rest, int post, bool kwargs, bool block, VALUE *v1, VALUE *v2, VALUE *v3, VALUE *v4, VALUE *v5, VALUE *v6, VALUE *v7, VALUE *v8, VALUE *v9, VALUE *v10));
-static inline int rb_tr_scan_args_kw_int(int kw_flag, int argc, VALUE *argv, int pre, int optional, bool rest, int post, bool kwargs, bool block, VALUE *v1, VALUE *v2, VALUE *v3, VALUE *v4, VALUE *v5, VALUE *v6, VALUE *v7, VALUE *v8, VALUE *v9, VALUE *v10) {
+ALWAYS_INLINE(static int rb_tr_scan_args_kw_int(int kw_flag, int argc, VALUE *argv, struct rb_tr_scan_args_parse_data parse_data, VALUE *v1, VALUE *v2, VALUE *v3, VALUE *v4, VALUE *v5, VALUE *v6, VALUE *v7, VALUE *v8, VALUE *v9, VALUE *v10));
+static inline int rb_tr_scan_args_kw_int(int kw_flag, int argc, VALUE *argv, struct rb_tr_scan_args_parse_data parse_data, VALUE *v1, VALUE *v2, VALUE *v3, VALUE *v4, VALUE *v5, VALUE *v6, VALUE *v7, VALUE *v8, VALUE *v9, VALUE *v10) {
 
   int keyword_given = 0;
   int last_hash_keyword = 0;
@@ -230,12 +234,12 @@ static inline int rb_tr_scan_args_kw_int(int kw_flag, int argc, VALUE *argv, int
 
   // Check we have enough arguments
 
-  if (pre + post > argc) {
+  if (parse_data.pre + parse_data.post > argc) {
     rb_raise(rb_eArgError, "not enough arguments for required");
   }
 
-  const int n_mand = pre + post;
-  const int n_opt = optional;
+  const int n_mand = parse_data.pre + parse_data.post;
+  const int n_opt = parse_data.optional;
 
   // Read arguments
 
@@ -256,7 +260,7 @@ static inline int rb_tr_scan_args_kw_int(int kw_flag, int argc, VALUE *argv, int
   if (argc > 0) {
     VALUE last = argv[argc - 1];
 
-    if (kwargs && n_mand < argc) {
+    if (parse_data.kwargs && n_mand < argc) {
       if (keyword_given) {
         if (!RB_TYPE_P(last, T_HASH)) {
           rb_warn("Keyword flag set when calling rb_scan_args, but last entry is not a hash");
@@ -271,8 +275,8 @@ static inline int rb_tr_scan_args_kw_int(int kw_flag, int argc, VALUE *argv, int
            option hash only if it is not ambiguous; i.e. '*' is
            not specified and arguments are given more than sufficient.
            This will be removed in Ruby 3. */
-        if (rest || argc <= n_mand + n_opt) {
-          kwargs = false;
+        if (parse_data.rest || argc <= n_mand + n_opt) {
+          parse_data.kwargs = false;
           erased_kwargs = true;
           rb_warn("The last argument is nil, treating as empty keywords");
         }
@@ -280,7 +284,7 @@ static inline int rb_tr_scan_args_kw_int(int kw_flag, int argc, VALUE *argv, int
       else {
         hash = rb_check_hash_type(last);
         if (NIL_P(hash)) {
-          kwargs = false;
+          parse_data.kwargs = false;
           erased_kwargs = true;
         }
       }
@@ -290,20 +294,20 @@ static inline int rb_tr_scan_args_kw_int(int kw_flag, int argc, VALUE *argv, int
         if (!polyglot_as_boolean(RUBY_CEXT_INVOKE_NO_WRAP("test_kwargs", argv[argc - 1], Qfalse))) {
           // Does not handle the case where "The last argument is split into positional and keyword parameters"
           // Instead assumes that it is all one hash
-          kwargs = false;
+          parse_data.kwargs = false;
           erased_kwargs = true;
         }
       }
     }
-    else if (kwargs && keyword_given && n_mand == argc) {
+    else if (parse_data.kwargs && keyword_given && n_mand == argc) {
       /* Warn if treating keywords as positional, as in Ruby 3, this will be an error */
       rb_warn("Passing the keyword argument as the last hash parameter is deprecated");
     }
   }
 
-  int trailing = post;
+  int trailing = parse_data.post;
 
-  if (kwargs) {
+  if (parse_data.kwargs) {
     trailing++;
   }
 
@@ -312,31 +316,31 @@ static inline int rb_tr_scan_args_kw_int(int kw_flag, int argc, VALUE *argv, int
 
     VALUE arg;
 
-    if (pre > 0 || optional > 0) {
-      if (argn - pre < argc - trailing) {
+    if (parse_data.pre > 0 || parse_data.optional > 0) {
+      if (argn - parse_data.pre < argc - trailing) {
         arg = argv[argn];
         argn++;
       } else {
         arg = Qnil;
       }
 
-      if (pre > 0) {
-        pre--;
+      if (parse_data.pre > 0) {
+        parse_data.pre--;
       } else {
-        optional--;
+        parse_data.optional--;
       }
-    } else if (rest && !taken_rest) {
+    } else if (parse_data.rest && !taken_rest) {
       arg = rb_ary_new();
       while (argn < argc - trailing) {
         rb_ary_push(arg, argv[argn]);
         argn++;
       }
       taken_rest = true;
-    } else if (post > 0) {
+    } else if (parse_data.post > 0) {
       arg = argv[argn];
       argn++;
-      post--;
-    } else if (kwargs && !taken_kwargs) {
+      parse_data.post--;
+    } else if (parse_data.kwargs && !taken_kwargs) {
        if (argn < argc) {
         arg = argv[argn];
         RUBY_CEXT_INVOKE_NO_WRAP("test_kwargs", arg, Qtrue);
@@ -349,7 +353,7 @@ static inline int rb_tr_scan_args_kw_int(int kw_flag, int argc, VALUE *argv, int
     } else if (erased_kwargs && !taken_kwargs) {
       arg = Qnil;
       taken_kwargs = true;
-    } else if (block && !taken_block) {
+    } else if (parse_data.block && !taken_block) {
       if (rb_block_given_p()) {
         arg = rb_block_proc();
       } else {
@@ -385,7 +389,7 @@ static inline int rb_tr_scan_args_kw_int(int kw_flag, int argc, VALUE *argv, int
   }
 
   if (argn < argc) {
-	rb_error_arity(argc, n_mand, rest ? UNLIMITED_ARGUMENTS : n_mand + n_opt);
+	rb_error_arity(argc, n_mand, parse_data.rest ? UNLIMITED_ARGUMENTS : n_mand + n_opt);
   }
 
   return argc;
@@ -395,16 +399,11 @@ ALWAYS_INLINE(static int rb_tr_scan_args_kw_non_const(int kw_flag, int argc, VAL
 static inline int rb_tr_scan_args_kw_non_const(int kw_flag, int argc, VALUE *argv, const char *format, VALUE *v1, VALUE *v2, VALUE *v3, VALUE *v4, VALUE *v5, VALUE *v6, VALUE *v7, VALUE *v8, VALUE *v9, VALUE *v10) {
 
   const char *formatp = format;
-  int pre = 0;
-  int optional = 0;
-  bool rest;
-  int post = 0;
-  bool kwargs;
-  bool block;
+  struct rb_tr_scan_args_parse_data parse_data = {0, 0, false, 0, false, false};
 
-  rb_tr_scan_args_kw_parse(format, &pre, &optional, &rest, &post, &kwargs, &block);
+  rb_tr_scan_args_kw_parse(format, &parse_data);
 
-  return rb_tr_scan_args_kw_int(kw_flag, argc, argv, pre, optional, rest, post, kwargs, block, v1, v2, v3, v4, v5, v6, v7, v8, v9, v10);
+  return rb_tr_scan_args_kw_int(kw_flag, argc, argv, parse_data, v1, v2, v3, v4, v5, v6, v7, v8, v9, v10);
 }
 
 #define rb_iv_get(obj, name) \
diff --git a/mx.truffleruby/env_files.md b/mx.truffleruby/env_files.md
new file mode 100644
index 000000000000..a3555163f52a
--- /dev/null
+++ b/mx.truffleruby/env_files.md
@@ -0,0 +1,14 @@
+Here is how the various env files relate to each other:
+* `jvm`
+  * `jvm-ce`: + Graal CE
+    * `jvm-ce-ntl`: + native toolchain launchers
+      * `jvm-ce-libgraal`: + libgraal
+      * `native`: + librubyvm
+  * `jvm-ee`: + Graal EE
+    * `jvm-ee-ntl`: + native toolchain launchers
+      * `jvm-ee-libgraal`: + libgraal
+      * `native-ee`: + librubyvm
+        * `native-ee-g1`: + Native Image G1
+  * `jvm-gu`: + Graal Updater
+  * `jvm-js`: + Graal.js
+  * `jvm-py`: + GraalPython
diff --git a/mx.truffleruby/jvm-ce b/mx.truffleruby/jvm-ce
index de1c3a3bbeee..cb2aaf53b25a 100644
--- a/mx.truffleruby/jvm-ce
+++ b/mx.truffleruby/jvm-ce
@@ -1,2 +1,2 @@
-DYNAMIC_IMPORTS=/compiler,/tools
-COMPONENTS=TruffleRuby,GraalVM compiler,suite:tools
+DYNAMIC_IMPORTS=/tools,/compiler
+COMPONENTS=TruffleRuby,suite:tools,GraalVM compiler
diff --git a/mx.truffleruby/jvm-ce-libgraal b/mx.truffleruby/jvm-ce-libgraal
index d887bdf894b6..414053331693 100644
--- a/mx.truffleruby/jvm-ce-libgraal
+++ b/mx.truffleruby/jvm-ce-libgraal
@@ -1,5 +1,3 @@
-DYNAMIC_IMPORTS=/compiler,/substratevm,/tools
-COMPONENTS=TruffleRuby,GraalVM compiler,SubstrateVM,LibGraal,suite:tools
-# NATIVE_IMAGES=lib:jvmcicompiler,graalvm-native-*
-FORCE_BASH_LAUNCHERS=truffleruby
-SKIP_LIBRARIES=false
+DYNAMIC_IMPORTS=/tools,/compiler,/substratevm
+COMPONENTS=TruffleRuby,suite:tools,GraalVM compiler,SubstrateVM,LibGraal
+NATIVE_IMAGES=suite:sulong,lib:jvmcicompiler
diff --git a/mx.truffleruby/jvm-ce-ntl b/mx.truffleruby/jvm-ce-ntl
index 4e693a88f8f0..d364bb0a3188 100644
--- a/mx.truffleruby/jvm-ce-ntl
+++ b/mx.truffleruby/jvm-ce-ntl
@@ -1,6 +1,3 @@
-# "ntl" stands for native toolchain launchers
-DYNAMIC_IMPORTS=/substratevm,/tools
-COMPONENTS=TruffleRuby,SubstrateVM,suite:tools
-# NATIVE_IMAGES=graalvm-native-*
-FORCE_BASH_LAUNCHERS=truffleruby
-DISABLE_INSTALLABLES=false
+DYNAMIC_IMPORTS=/tools,/compiler,/substratevm
+COMPONENTS=TruffleRuby,suite:tools,GraalVM compiler,SubstrateVM
+NATIVE_IMAGES=suite:sulong
diff --git a/mx.truffleruby/jvm-ee b/mx.truffleruby/jvm-ee
index af58b9fd8910..ce1c3831ea87 100644
--- a/mx.truffleruby/jvm-ee
+++ b/mx.truffleruby/jvm-ee
@@ -1,2 +1,2 @@
-DYNAMIC_IMPORTS=/graal-enterprise,/tools
-COMPONENTS=TruffleRuby,GraalVM enterprise compiler,suite:tools
+DYNAMIC_IMPORTS=/tools,/graal-enterprise
+COMPONENTS=TruffleRuby,suite:tools,GraalVM enterprise compiler
diff --git a/mx.truffleruby/jvm-ee-libgraal b/mx.truffleruby/jvm-ee-libgraal
index b8f9ee591857..a19bac6ef4b5 100644
--- a/mx.truffleruby/jvm-ee-libgraal
+++ b/mx.truffleruby/jvm-ee-libgraal
@@ -1,5 +1,3 @@
-DYNAMIC_IMPORTS=/graal-enterprise,/substratevm-enterprise,/tools
-COMPONENTS=TruffleRuby,GraalVM enterprise compiler,SubstrateVM Enterprise,LibGraal,suite:tools
-# NATIVE_IMAGES=lib:jvmcicompiler,graalvm-native-*
-FORCE_BASH_LAUNCHERS=truffleruby
-SKIP_LIBRARIES=false
+DYNAMIC_IMPORTS=/tools,/graal-enterprise,/substratevm-enterprise
+COMPONENTS=TruffleRuby,suite:tools,GraalVM enterprise compiler,SubstrateVM Enterprise,LibGraal
+NATIVE_IMAGES=suite:sulong,lib:jvmcicompiler
diff --git a/mx.truffleruby/jvm-ee-ntl b/mx.truffleruby/jvm-ee-ntl
new file mode 100644
index 000000000000..dcb14707ed35
--- /dev/null
+++ b/mx.truffleruby/jvm-ee-ntl
@@ -0,0 +1,3 @@
+DYNAMIC_IMPORTS=/tools,/graal-enterprise,/substratevm-enterprise
+COMPONENTS=TruffleRuby,suite:tools,GraalVM enterprise compiler,SubstrateVM Enterprise
+NATIVE_IMAGES=suite:sulong
diff --git a/mx.truffleruby/jvm-gu b/mx.truffleruby/jvm-gu
index 69c5cc09dc44..98da521b9f24 100644
--- a/mx.truffleruby/jvm-gu
+++ b/mx.truffleruby/jvm-gu
@@ -1,2 +1,2 @@
-DYNAMIC_IMPORTS=/vm,/tools
-COMPONENTS=TruffleRuby,gu,suite:tools
+DYNAMIC_IMPORTS=/tools,/vm
+COMPONENTS=TruffleRuby,suite:tools,gu
diff --git a/mx.truffleruby/jvm-js b/mx.truffleruby/jvm-js
index 3d35b01e18e4..a51398c1cb65 100644
--- a/mx.truffleruby/jvm-js
+++ b/mx.truffleruby/jvm-js
@@ -1,2 +1,2 @@
 DYNAMIC_IMPORTS=/tools,/graal-js
-COMPONENTS=TruffleRuby,Graal.js,suite:tools
+COMPONENTS=TruffleRuby,suite:tools,Graal.js
diff --git a/mx.truffleruby/jvm-py b/mx.truffleruby/jvm-py
index d9c097b25416..5179668c2560 100644
--- a/mx.truffleruby/jvm-py
+++ b/mx.truffleruby/jvm-py
@@ -1,2 +1,2 @@
 DYNAMIC_IMPORTS=/tools,graalpython
-COMPONENTS=TruffleRuby,Graal.Python,suite:tools
+COMPONENTS=TruffleRuby,suite:tools,Graal.Python
diff --git a/mx.truffleruby/native b/mx.truffleruby/native
index ce798f751f6e..9fa3f5ab3613 100644
--- a/mx.truffleruby/native
+++ b/mx.truffleruby/native
@@ -1,4 +1,5 @@
-DYNAMIC_IMPORTS=/substratevm,/tools
-COMPONENTS=TruffleRuby,SubstrateVM,suite:tools
-NATIVE_IMAGES=true
+DYNAMIC_IMPORTS=/tools,/compiler,/substratevm
+COMPONENTS=TruffleRuby,suite:tools,GraalVM compiler,SubstrateVM
+NATIVE_IMAGES=suite:sulong,lib:rubyvm
+# To also create the standalone
 DISABLE_INSTALLABLES=false
diff --git a/mx.truffleruby/native-ee b/mx.truffleruby/native-ee
index 7f1f4e069e5f..710ab073d1d2 100644
--- a/mx.truffleruby/native-ee
+++ b/mx.truffleruby/native-ee
@@ -1,5 +1,6 @@
-DYNAMIC_IMPORTS=/substratevm-enterprise,/tools
-COMPONENTS=TruffleRuby,SubstrateVM Enterprise,suite:tools
-NATIVE_IMAGES=true
+DYNAMIC_IMPORTS=/tools,/graal-enterprise,/substratevm-enterprise
+COMPONENTS=TruffleRuby,suite:tools,GraalVM enterprise compiler,SubstrateVM Enterprise
+NATIVE_IMAGES=suite:sulong,lib:rubyvm
 EXTRA_IMAGE_BUILDER_ARGUMENTS=rubyvm:-H:+AuxiliaryEngineCache rubyvm:-H:ReservedAuxiliaryImageBytes=1073741824
+# To also create the standalone
 DISABLE_INSTALLABLES=false
diff --git a/mx.truffleruby/native-ee-g1 b/mx.truffleruby/native-ee-g1
index 0858d456b18b..b3cbb9eb63ac 100644
--- a/mx.truffleruby/native-ee-g1
+++ b/mx.truffleruby/native-ee-g1
@@ -1,5 +1,6 @@
-DYNAMIC_IMPORTS=/substratevm-enterprise,substratevm-enterprise-gcs,/tools
-COMPONENTS=TruffleRuby,SubstrateVM Enterprise,SubstrateVM Enterprise GC,suite:tools
-NATIVE_IMAGES=true
+DYNAMIC_IMPORTS=/tools,/graal-enterprise,/substratevm-enterprise,substratevm-enterprise-gcs
+COMPONENTS=TruffleRuby,suite:tools,GraalVM enterprise compiler,SubstrateVM Enterprise,SubstrateVM Enterprise GC
+NATIVE_IMAGES=suite:sulong,lib:rubyvm
 EXTRA_IMAGE_BUILDER_ARGUMENTS=rubyvm:-H:+UseG1GC
+# To also create the standalone
 DISABLE_INSTALLABLES=false
diff --git a/mx.truffleruby/suite.py b/mx.truffleruby/suite.py
index eb2c77942f06..e1b009016567 100644
--- a/mx.truffleruby/suite.py
+++ b/mx.truffleruby/suite.py
@@ -1,5 +1,5 @@
 suite = {
-    "mxversion": "5.309.0",
+    "mxversion": "6.0.1",
     "name": "truffleruby",
 
     "imports": {
@@ -7,7 +7,7 @@
             {
                 "name": "regex",
                 "subdir": True,
-                "version": "ee11f21138f4ce3b4d4a178436dc5e7c5ed3264f",
+                "version": "bccc6d539bfde23d1d4ed7b4d3f647777c5560db",
                 "urls": [
                     {"url": "https://github.com/oracle/graal.git", "kind": "git"},
                     {"url": "https://curio.ssw.jku.at/nexus/content/repositories/snapshots", "kind": "binary"},
@@ -16,7 +16,7 @@
             {
                 "name": "sulong",
                 "subdir": True,
-                "version": "ee11f21138f4ce3b4d4a178436dc5e7c5ed3264f",
+                "version": "bccc6d539bfde23d1d4ed7b4d3f647777c5560db",
                 "urls": [
                     {"url": "https://github.com/oracle/graal.git", "kind": "git"},
                     {"url": "https://curio.ssw.jku.at/nexus/content/repositories/snapshots", "kind": "binary"},
diff --git a/spec/ruby/core/file/open_spec.rb b/spec/ruby/core/file/open_spec.rb
index c7dd34d5c61d..172978057029 100644
--- a/spec/ruby/core/file/open_spec.rb
+++ b/spec/ruby/core/file/open_spec.rb
@@ -494,6 +494,14 @@
     File.open(@file, "w") { |f| f.puts "testing" }
     File.size(@file).should > 0
     File.open(@file, "rb+") do |f|
+      f.binmode?.should == true
+      f.external_encoding.should == Encoding::ASCII_8BIT
+      f.pos.should == 0
+      f.should_not.eof?
+    end
+    File.open(@file, "r+b") do |f|
+      f.binmode?.should == true
+      f.external_encoding.should == Encoding::ASCII_8BIT
       f.pos.should == 0
       f.should_not.eof?
     end
diff --git a/spec/ruby/core/float/divide_spec.rb b/spec/ruby/core/float/divide_spec.rb
index d8f71a6b982c..72ab7527bd52 100644
--- a/spec/ruby/core/float/divide_spec.rb
+++ b/spec/ruby/core/float/divide_spec.rb
@@ -36,4 +36,8 @@
     -> { 13.0 / "10"    }.should raise_error(TypeError)
     -> { 13.0 / :symbol }.should raise_error(TypeError)
   end
+
+  it "divides correctly by Rational numbers" do
+    (1.2345678901234567 / Rational(1, 10000000000000000000)).should == 1.2345678901234567e+19
+  end
 end
diff --git a/spec/ruby/core/integer/fdiv_spec.rb b/spec/ruby/core/integer/fdiv_spec.rb
index d99a19eb0f99..d9ea2fdf8d57 100644
--- a/spec/ruby/core/integer/fdiv_spec.rb
+++ b/spec/ruby/core/integer/fdiv_spec.rb
@@ -55,6 +55,11 @@
     num.fdiv(den).should == -0.5555555555555556
   end
 
+  it "rounds to the correct float for bignum denominators" do
+    1.fdiv(10**324).should == 0.0
+    1.fdiv(10**323).should == 1.0e-323
+  end
+
   it "performs floating-point division between self and a Float" do
     8.fdiv(9.0).should be_close(0.888888888888889, TOLERANCE)
   end
diff --git a/spec/ruby/core/module/class_variables_spec.rb b/spec/ruby/core/module/class_variables_spec.rb
index fd7aa93aa8ba..e155f1deac25 100644
--- a/spec/ruby/core/module/class_variables_spec.rb
+++ b/spec/ruby/core/module/class_variables_spec.rb
@@ -23,4 +23,12 @@
     c.extend ModuleSpecs::MVars
     c.class_variables.should_not include(:@@mvar)
   end
+
+  it "returns the correct class variables when inherit is given" do
+    ModuleSpecs::SubCVars.class_variables(false).should == [:@@sub]
+    ModuleSpecs::SubCVars.new.singleton_class.class_variables(false).should == []
+
+    ModuleSpecs::SubCVars.class_variables(true).should == [:@@sub, :@@cls, :@@meta]
+    ModuleSpecs::SubCVars.new.singleton_class.class_variables(true).should ==  [:@@sub, :@@cls, :@@meta]
+  end
 end
diff --git a/spec/ruby/core/module/fixtures/classes.rb b/spec/ruby/core/module/fixtures/classes.rb
index 40777cdbbdc2..a64f672b2f1a 100644
--- a/spec/ruby/core/module/fixtures/classes.rb
+++ b/spec/ruby/core/module/fixtures/classes.rb
@@ -352,6 +352,10 @@ def meta
     end
   end
 
+  class SubCVars < CVars
+    @@sub = :sub
+  end
+
   module MVars
     @@mvar = :mvar
   end
diff --git a/src/main/c/cext/args.c b/src/main/c/cext/args.c
index 85bfb6d54b34..ff1b6acd025d 100644
--- a/src/main/c/cext/args.c
+++ b/src/main/c/cext/args.c
@@ -103,43 +103,43 @@ int rb_get_kwargs(VALUE keyword_hash, const ID *table, int required, int optiona
   return extracted;
 }
 
-void rb_tr_scan_args_kw_parse(const char *format, int *pre, int *optional, bool *rest, int *post, bool *kwargs, bool *block) {
+void rb_tr_scan_args_kw_parse(const char *format, struct rb_tr_scan_args_parse_data *parse_data) {
   const char *formatp = format;
 
   if (isdigit(*formatp)) {
-    *pre = *formatp - '0';
+    parse_data->pre = *formatp - '0';
     formatp++;
 
     if (isdigit(*formatp)) {
-      *optional = *formatp - '0';
+      parse_data->optional = *formatp - '0';
       formatp++;
     }
   }
 
   if (*formatp == '*') {
-    *rest = true;
+    parse_data->rest = true;
     formatp++;
   } else {
-    *rest = false;
+    parse_data->rest = false;
   }
 
   if (isdigit(*formatp)) {
-    *post = *formatp - '0';
+    parse_data->post = *formatp - '0';
     formatp++;
   }
 
   if (*formatp == ':') {
-    *kwargs = true;
+    parse_data->kwargs = true;
     formatp++;
   } else {
-    *kwargs = false;
+    parse_data->kwargs = false;
   }
 
   if (*formatp == '&') {
-    *block = true;
+    parse_data->block = true;
     formatp++;
   } else {
-    *block = false;
+    parse_data->block = false;
   }
 
   if (*formatp != '\0') {
diff --git a/src/main/java/org/truffleruby/core/module/ModuleNodes.java b/src/main/java/org/truffleruby/core/module/ModuleNodes.java
index a64abeb9d338..24bc62e02252 100644
--- a/src/main/java/org/truffleruby/core/module/ModuleNodes.java
+++ b/src/main/java/org/truffleruby/core/module/ModuleNodes.java
@@ -12,6 +12,7 @@
 import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.HashSet;
+import java.util.LinkedHashSet;
 import java.util.List;
 import java.util.Map;
 import java.util.Map.Entry;
@@ -884,15 +885,22 @@ protected Object setClassVariable(RubyModule module, String name, Object value,
 
     }
 
-    @CoreMethod(names = "class_variables")
-    public abstract static class ClassVariablesNode extends CoreMethodArrayArgumentsNode {
+    @CoreMethod(names = "class_variables", optional = 1)
+    @NodeChild(value = "module", type = RubyNode.class)
+    @NodeChild(value = "inherit", type = RubyBaseNodeWithExecute.class)
+    public abstract static class ClassVariablesNode extends CoreMethodNode {
+
+        @CreateCast("inherit")
+        protected RubyBaseNodeWithExecute coerceToBoolean(RubyBaseNodeWithExecute inherit) {
+            return BooleanCastWithDefaultNode.create(true, inherit);
+        }
 
         @TruffleBoundary
         @Specialization
-        protected RubyArray getClassVariables(RubyModule module) {
-            final Set<Object> variables = new HashSet<>();
+        protected RubyArray getClassVariables(RubyModule module, boolean inherit) {
+            final Set<Object> variables = new LinkedHashSet<>();
 
-            ModuleOperations.classVariableLookup(module, m -> {
+            ModuleOperations.classVariableLookup(module, inherit, m -> {
                 final ClassVariableStorage classVariableStorage = m.fields.getClassVariables();
                 for (Object key : classVariableStorage.getShape().getKeys()) {
                     variables.add(getSymbol((String) key));
diff --git a/src/main/java/org/truffleruby/core/module/ModuleOperations.java b/src/main/java/org/truffleruby/core/module/ModuleOperations.java
index a1fbcc7dc7cc..60ca23fd0e7e 100644
--- a/src/main/java/org/truffleruby/core/module/ModuleOperations.java
+++ b/src/main/java/org/truffleruby/core/module/ModuleOperations.java
@@ -664,6 +664,7 @@ public static void setClassVariable(RubyLanguage language, RubyContext context,
     private static boolean trySetClassVariable(RubyModule topModule, String name, Object value) {
         return classVariableLookup(
                 topModule,
+                true,
                 module -> module.fields.getClassVariables().putIfPresent(
                         name,
                         value,
@@ -689,13 +690,17 @@ public static Object removeClassVariable(ModuleFields fields, RubyContext contex
     }
 
     @TruffleBoundary
-    public static <R> R classVariableLookup(RubyModule module, Function<RubyModule, R> action) {
+    public static <R> R classVariableLookup(RubyModule module, boolean inherit, Function<RubyModule, R> action) {
         // Look in the current module
         R result = action.apply(module);
         if (result != null) {
             return result;
         }
 
+        if (!inherit) {
+            return null;
+        }
+
         // If singleton class of a module, check the attached module.
         if (module instanceof RubyClass) {
             RubyClass klass = (RubyClass) module;
diff --git a/src/main/java/org/truffleruby/core/numeric/IntegerNodes.java b/src/main/java/org/truffleruby/core/numeric/IntegerNodes.java
index 4404c0935182..d1afce7ba7cf 100644
--- a/src/main/java/org/truffleruby/core/numeric/IntegerNodes.java
+++ b/src/main/java/org/truffleruby/core/numeric/IntegerNodes.java
@@ -286,7 +286,7 @@ protected Object mul(Object a, Object b,
 
     }
 
-    @Primitive(name = "interger_fdiv")
+    @Primitive(name = "integer_fdiv")
     public abstract static class FDivNode extends PrimitiveArrayArgumentsNode {
 
         @Specialization
@@ -302,19 +302,19 @@ protected double fDivLongLong(long num, long den) {
         @TruffleBoundary
         @Specialization
         protected double fDivLongBig(long num, RubyBignum den) {
-            return new BigDecimal(num).divide(new BigDecimal(den.value), 17, RoundingMode.HALF_UP).doubleValue();
+            return new BigDecimal(num).divide(new BigDecimal(den.value), 323, RoundingMode.HALF_UP).doubleValue();
         }
 
         @TruffleBoundary
         @Specialization
         protected double fDivBigLong(RubyBignum num, long den) {
-            return new BigDecimal(num.value).divide(new BigDecimal(den), 17, RoundingMode.HALF_UP).doubleValue();
+            return new BigDecimal(num.value).divide(new BigDecimal(den), 323, RoundingMode.HALF_UP).doubleValue();
         }
 
         @TruffleBoundary
         @Specialization
         protected double fDivBigBig(RubyBignum num, RubyBignum den) {
-            return new BigDecimal(num.value).divide(new BigDecimal(den.value), 17, RoundingMode.HALF_UP).doubleValue();
+            return new BigDecimal(num.value).divide(new BigDecimal(den.value), 323, RoundingMode.HALF_UP).doubleValue();
         }
 
     }
diff --git a/src/main/java/org/truffleruby/language/arguments/SplatToArgsNode.java b/src/main/java/org/truffleruby/language/arguments/SplatToArgsNode.java
index 4a9490313670..e3c435b1e790 100644
--- a/src/main/java/org/truffleruby/language/arguments/SplatToArgsNode.java
+++ b/src/main/java/org/truffleruby/language/arguments/SplatToArgsNode.java
@@ -26,7 +26,7 @@ public SplatToArgsNode() {
         stores = ArrayStoreLibrary.getFactory().createDispatched(ArrayGuards.storageStrategyLimit());
     }
 
-    public Object[] execute(Object receiver, Object[] rubyArgs, RubyArray splatted) {
+    public Object[] execute(Object receiver, RubyArray splatted) {
         int size = splatSizeProfile.profile(splatted.size);
         Object store = splatted.store;
         final Object[] newArgs = RubyArguments.allocate(size);
diff --git a/src/main/java/org/truffleruby/language/dispatch/DispatchNode.java b/src/main/java/org/truffleruby/language/dispatch/DispatchNode.java
index e728bb9f2702..9d99fdccf872 100644
--- a/src/main/java/org/truffleruby/language/dispatch/DispatchNode.java
+++ b/src/main/java/org/truffleruby/language/dispatch/DispatchNode.java
@@ -10,6 +10,7 @@
 package org.truffleruby.language.dispatch;
 
 import com.oracle.truffle.api.CompilerDirectives;
+import com.oracle.truffle.api.CompilerDirectives.CompilationFinal;
 import com.oracle.truffle.api.RootCallTarget;
 import com.oracle.truffle.api.frame.Frame;
 import com.oracle.truffle.api.interop.TruffleObject;
@@ -82,7 +83,7 @@ public static DispatchNode getUncached() {
     @Child protected ToSymbolNode toSymbol;
 
     protected final ConditionProfile methodMissing;
-    protected final BranchProfile methodMissingMissing;
+    @CompilationFinal private boolean methodMissingMissingProfile;
 
     protected DispatchNode(
             DispatchConfiguration config,
@@ -96,7 +97,6 @@ protected DispatchNode(
         this.methodLookup = methodLookup;
         this.callNode = callNode;
         this.methodMissing = methodMissing;
-        this.methodMissingMissing = methodMissingMissing;
     }
 
     protected DispatchNode(DispatchConfiguration config) {
@@ -280,14 +280,24 @@ public final Object dispatch(Frame frame, Object receiver, String methodName, Ob
         return dispatch(frame, receiver, methodName, rubyArgs, null);
     }
 
-    public final Object dispatch(Frame frame, Object receiver, String methodName, Object[] rubyArgs,
+    public Object dispatch(Frame frame, Object receiver, String methodName, Object[] rubyArgs,
             LiteralCallNode literalCallNode) {
+        return dispatchInternal(frame, receiver, methodName, rubyArgs, literalCallNode,
+                metaclassNode, methodLookup, methodMissing, callNode);
+    }
+
+    protected final Object dispatchInternal(Frame frame, Object receiver, String methodName, Object[] rubyArgs,
+            LiteralCallNode literalCallNode,
+            MetaClassNode metaClassNode,
+            LookupMethodNode lookupMethodNode,
+            ConditionProfile methodMissingProfile,
+            CallInternalMethodNode callNode) {
         assert RubyArguments.getSelf(rubyArgs) == receiver;
 
-        final RubyClass metaclass = metaclassNode.execute(receiver);
-        final InternalMethod method = methodLookup.execute(frame, metaclass, methodName, config);
+        final RubyClass metaclass = metaClassNode.execute(receiver);
+        final InternalMethod method = lookupMethodNode.execute(frame, metaclass, methodName, config);
 
-        if (methodMissing.profile(method == null || method.isUndefined())) {
+        if (methodMissingProfile.profile(method == null || method.isUndefined())) {
             switch (config.missingBehavior) {
                 case RETURN_MISSING:
                     return MISSING;
@@ -320,7 +330,7 @@ private Object callMethodMissing(Frame frame, Object receiver, String methodName
                 literalCallNode);
 
         if (result == MISSING) {
-            methodMissingMissing.enter();
+            methodMissingMissingProfileEnter();
             throw new RaiseException(getContext(), coreExceptions().noMethodErrorFromMethodMissing(
                     ExceptionFormatter.NO_METHOD_ERROR,
                     receiver,
@@ -359,6 +369,13 @@ protected DispatchNode getMethodMissingNode() {
         return callMethodMissing;
     }
 
+    protected void methodMissingMissingProfileEnter() {
+        if (!methodMissingMissingProfile) {
+            CompilerDirectives.transferToInterpreterAndInvalidate();
+            methodMissingMissingProfile = true;
+        }
+    }
+
     protected RubySymbol nameToSymbol(String methodName) {
         if (toSymbol == null) {
             CompilerDirectives.transferToInterpreterAndInvalidate();
@@ -404,13 +421,17 @@ private static final class Uncached extends DispatchNode {
         }
 
         protected Uncached(DispatchConfiguration config) {
-            super(
-                    config,
+            super(config, null, null, null, null, null);
+        }
+
+        @Override
+        public Object dispatch(Frame frame, Object receiver, String methodName, Object[] rubyArgs,
+                LiteralCallNode literalCallNode) {
+            return dispatchInternal(frame, receiver, methodName, rubyArgs, literalCallNode,
                     MetaClassNodeGen.getUncached(),
                     LookupMethodNodeGen.getUncached(),
-                    CallInternalMethodNodeGen.getUncached(),
                     ConditionProfile.getUncached(),
-                    BranchProfile.getUncached());
+                    CallInternalMethodNodeGen.getUncached());
         }
 
         @Override
@@ -423,6 +444,10 @@ protected DispatchNode getMethodMissingNode() {
             return DispatchNode.getUncached(DispatchConfiguration.PRIVATE_RETURN_MISSING_IGNORE_REFINEMENTS);
         }
 
+        @Override
+        protected void methodMissingMissingProfileEnter() {
+        }
+
         @Override
         protected RubySymbol nameToSymbol(String methodName) {
             return ToSymbolNode.getUncached().execute(methodName);
diff --git a/src/main/java/org/truffleruby/language/dispatch/InternalRespondToNode.java b/src/main/java/org/truffleruby/language/dispatch/InternalRespondToNode.java
index ff012e88d9af..e20db9eab6c8 100644
--- a/src/main/java/org/truffleruby/language/dispatch/InternalRespondToNode.java
+++ b/src/main/java/org/truffleruby/language/dispatch/InternalRespondToNode.java
@@ -66,7 +66,14 @@ protected InternalRespondToNode(DispatchConfiguration config) {
         this(config, MetaClassNode.create(), LookupMethodNode.create());
     }
 
-    public final boolean execute(Frame frame, Object receiver, String methodName) {
+    public boolean execute(Frame frame, Object receiver, String methodName) {
+        return executeInternal(frame, receiver, methodName, config, metaclassNode, methodLookup);
+    }
+
+    protected static boolean executeInternal(Frame frame, Object receiver, String methodName,
+            DispatchConfiguration config,
+            MetaClassNode metaclassNode,
+            LookupMethodNode methodLookup) {
         final RubyClass metaclass = metaclassNode.execute(receiver);
         final InternalMethod method = methodLookup.execute(frame, metaclass, methodName, config);
         return method != null && method.isDefined() && method.isImplemented();
@@ -83,7 +90,14 @@ private static final class Uncached extends InternalRespondToNode {
         }
 
         protected Uncached(DispatchConfiguration config) {
-            super(config, MetaClassNodeGen.getUncached(), LookupMethodNodeGen.getUncached());
+            super(config, null, null);
+        }
+
+        public boolean execute(Frame frame, Object receiver, String methodName) {
+            return executeInternal(frame, receiver, methodName,
+                    config,
+                    MetaClassNodeGen.getUncached(),
+                    LookupMethodNodeGen.getUncached());
         }
 
         @Override
diff --git a/src/main/java/org/truffleruby/language/dispatch/RubyCallNode.java b/src/main/java/org/truffleruby/language/dispatch/RubyCallNode.java
index a44e1c9e2419..49febfcb4445 100644
--- a/src/main/java/org/truffleruby/language/dispatch/RubyCallNode.java
+++ b/src/main/java/org/truffleruby/language/dispatch/RubyCallNode.java
@@ -192,7 +192,7 @@ private Object[] splatArgs(Object receiverObject, Object[] rubyArgs) {
             splatToArgs = insert(new SplatToArgsNode());
         }
 
-        return splatToArgs.execute(receiverObject, rubyArgs, (RubyArray) RubyArguments.getArgument(rubyArgs, 0));
+        return splatToArgs.execute(receiverObject, (RubyArray) RubyArguments.getArgument(rubyArgs, 0));
     }
 
     @Override
diff --git a/src/main/java/org/truffleruby/language/objects/MetaClassNode.java b/src/main/java/org/truffleruby/language/objects/MetaClassNode.java
index 6ef359d85229..126da39a63e7 100644
--- a/src/main/java/org/truffleruby/language/objects/MetaClassNode.java
+++ b/src/main/java/org/truffleruby/language/objects/MetaClassNode.java
@@ -9,6 +9,7 @@
  */
 package org.truffleruby.language.objects;
 
+import com.oracle.truffle.api.dsl.TypeSystemReference;
 import org.truffleruby.core.encoding.RubyEncoding;
 import org.truffleruby.core.klass.RubyClass;
 import org.truffleruby.core.numeric.RubyBignum;
@@ -16,6 +17,7 @@
 import org.truffleruby.core.symbol.RubySymbol;
 import org.truffleruby.core.string.ImmutableRubyString;
 import org.truffleruby.language.Nil;
+import org.truffleruby.language.NoImplicitCastsToLong;
 import org.truffleruby.language.RubyBaseNode;
 import org.truffleruby.language.RubyDynamicObject;
 
@@ -24,6 +26,7 @@
 import com.oracle.truffle.api.dsl.Specialization;
 
 @GenerateUncached
+@TypeSystemReference(NoImplicitCastsToLong.class)
 public abstract class MetaClassNode extends RubyBaseNode {
 
     public static MetaClassNode create() {
diff --git a/src/main/java/org/truffleruby/language/objects/classvariables/LookupClassVariableStorageNode.java b/src/main/java/org/truffleruby/language/objects/classvariables/LookupClassVariableStorageNode.java
index eec33aa020d2..a83d1e4d8850 100644
--- a/src/main/java/org/truffleruby/language/objects/classvariables/LookupClassVariableStorageNode.java
+++ b/src/main/java/org/truffleruby/language/objects/classvariables/LookupClassVariableStorageNode.java
@@ -36,7 +36,7 @@ protected ClassVariableStorage lookupClassVariable(RubyModule module, String nam
     @Specialization(replaces = "lookupClassVariable")
     @TruffleBoundary
     protected ClassVariableStorage uncachedLookupClassVariable(RubyModule module, String name) {
-        return ModuleOperations.classVariableLookup(module, m -> {
+        return ModuleOperations.classVariableLookup(module, true, m -> {
             final ClassVariableStorage classVariables = m.fields.getClassVariables();
             if (classVariables.getShape().hasProperty(name)) {
                 return classVariables;
diff --git a/src/main/ruby/truffleruby/core/integer.rb b/src/main/ruby/truffleruby/core/integer.rb
index 0c2d00893235..16c7a96cece5 100644
--- a/src/main/ruby/truffleruby/core/integer.rb
+++ b/src/main/ruby/truffleruby/core/integer.rb
@@ -111,7 +111,7 @@ def divmod(b)
 
   def fdiv(n)
     if Primitive.object_kind_of?(n, Integer)
-      Primitive.interger_fdiv(self, n)
+      Primitive.integer_fdiv(self, n)
     else
       redo_coerced :fdiv, n
     end
diff --git a/src/main/ruby/truffleruby/core/io.rb b/src/main/ruby/truffleruby/core/io.rb
index 01f7e5df2628..bca52752b7b1 100644
--- a/src/main/ruby/truffleruby/core/io.rb
+++ b/src/main/ruby/truffleruby/core/io.rb
@@ -648,8 +648,8 @@ def self.normalize_options(mode, perm, options)
       mode, external, internal = mode.split(':')
       raise ArgumentError, 'invalid access mode' unless mode
 
-      binary = true  if mode[1] === ?b
-      binary = false if mode[1] === ?t
+      binary = true  if mode.include?(?b)
+      binary = false if mode.include?(?t)
     elsif mode
       binary = true  if (mode & BINARY) != 0
     end
diff --git a/tool/jt.rb b/tool/jt.rb
index 21c53847f6cb..c2c192e3a6c7 100755
--- a/tool/jt.rb
+++ b/tool/jt.rb
@@ -2330,11 +2330,11 @@ def bootstrap_toolchain
         with_color(TERM_COLOR_RED) do
           puts "\nNOTE: Set env variable JT_IMPORTS_DONT_ASK to always answer 'no' to this prompt.\n\n"
           puts scheckimports_output
-          input = ''
-          until %w(y n).include? input
+          begin
             print 'Do you want to checkout the supported version of graal as specified in truffleruby\'s suite.py? (runs `mx sforceimports`) [y/n] '
+            STDOUT.flush
             input = STDIN.gets.chomp
-          end
+          end until %w(y n).include? input
           puts ''
           input == 'y'
         end