diff --git a/.github/workflows/zjit-macos.yml b/.github/workflows/zjit-macos.yml
index f9282d64e84b0a..e68bd897fd55d2 100644
--- a/.github/workflows/zjit-macos.yml
+++ b/.github/workflows/zjit-macos.yml
@@ -93,7 +93,7 @@ jobs:
           rustup install ${{ matrix.rust_version }} --profile minimal
           rustup default ${{ matrix.rust_version }}
 
-      - uses: taiki-e/install-action@13608cbb45b01feb47ef444ab1a42dc41ad56f1a # v2.79.11
+      - uses: taiki-e/install-action@e49978b799e49ff429d162b7a30601a569ab6538 # v2.81.1
         with:
           tool: nextest@0.9
         if: ${{ matrix.test_task == 'zjit-check' }}
diff --git a/.github/workflows/zjit-ubuntu.yml b/.github/workflows/zjit-ubuntu.yml
index 1e7bec38599911..8d146b7bdc8cf5 100644
--- a/.github/workflows/zjit-ubuntu.yml
+++ b/.github/workflows/zjit-ubuntu.yml
@@ -119,7 +119,7 @@ jobs:
           ruby-version: '3.1'
           bundler: none
 
-      - uses: taiki-e/install-action@13608cbb45b01feb47ef444ab1a42dc41ad56f1a # v2.79.11
+      - uses: taiki-e/install-action@e49978b799e49ff429d162b7a30601a569ab6538 # v2.81.1
         with:
           tool: nextest@0.9
         if: ${{ matrix.test_task == 'zjit-check' }}
diff --git a/gc/gc.h b/gc/gc.h
index ea8056c6716f08..d147a3122a853a 100644
--- a/gc/gc.h
+++ b/gc/gc.h
@@ -219,12 +219,14 @@ hash_foreach_replace(st_data_t key, st_data_t value, st_data_t argp, int error)
 static int
 hash_replace_ref(st_data_t *key, st_data_t *value, st_data_t argp, int existing)
 {
-    if (rb_gc_location((VALUE)*key) != (VALUE)*key) {
-        *key = rb_gc_location((VALUE)*key);
+    VALUE new_key = rb_gc_location((VALUE)*key);
+    if (new_key != (VALUE)*key) {
+        *key = new_key;
     }
 
-    if (rb_gc_location((VALUE)*value) != (VALUE)*value) {
-        *value = rb_gc_location((VALUE)*value);
+    VALUE new_value = rb_gc_location((VALUE)*value);
+    if (new_value != (VALUE)*value) {
+        *value = new_value;
     }
 
     return ST_CONTINUE;
diff --git a/lib/rubygems/config_file.rb b/lib/rubygems/config_file.rb
index 19718829fccbdd..d5e9eb4e33aec6 100644
--- a/lib/rubygems/config_file.rb
+++ b/lib/rubygems/config_file.rb
@@ -26,9 +26,22 @@
 # RubyGems options use symbol keys.  Valid options are:
 #
 # +:backtrace+:: See #backtrace
-# +:sources+:: Sets Gem::sources
+# +:bulk_threshold+:: See #bulk_threshold
 # +:verbose+:: See #verbose
+# +:update_sources+:: See #update_sources
 # +:concurrent_downloads+:: See #concurrent_downloads
+# +:cert_expiration_length_days+:: See #cert_expiration_length_days
+# +:install_extension_in_lib+:: See #install_extension_in_lib
+# +:ipv4_fallback_enabled+:: See #ipv4_fallback_enabled
+# +:global_gem_cache+:: See #global_gem_cache
+# +:use_psych+:: See #use_psych
+# +:gemhome+:: See #home
+# +:gempath+:: See #path
+# +:sources+:: Sets Gem::sources
+# +:disable_default_gem_server+:: See #disable_default_gem_server
+# +:ssl_verify_mode+:: See #ssl_verify_mode
+# +:ssl_ca_cert+:: See #ssl_ca_cert
+# +:ssl_client_cert+:: See #ssl_client_cert
 #
 # gemrc files may exist in various locations and are read and merged in
 # the following order:
diff --git a/test/rubygems/test_gem_config_file.rb b/test/rubygems/test_gem_config_file.rb
index e85d00530e3089..3c79cb0762d783 100644
--- a/test/rubygems/test_gem_config_file.rb
+++ b/test/rubygems/test_gem_config_file.rb
@@ -53,6 +53,7 @@ def test_initialize
       fp.puts ":sources:"
       fp.puts "  - http://more-gems.example.com"
       fp.puts "install: --wrappers"
+      fp.puts ":gemhome: /tmp/gems"
       fp.puts ":gempath:"
       fp.puts "- /usr/ruby/1.8/lib/ruby/gems/1.8"
       fp.puts "- /var/ruby/1.8/gem_home"
@@ -61,6 +62,7 @@ def test_initialize
       fp.puts ":cert_expiration_length_days: 28"
       fp.puts ":install_extension_in_lib: false"
       fp.puts ":ipv4_fallback_enabled: true"
+      fp.puts ":use_psych: true"
     end
 
     util_config_file
@@ -70,6 +72,7 @@ def test_initialize
     assert_equal false, @cfg.update_sources
     assert_equal %w[http://more-gems.example.com], @cfg.sources
     assert_equal "--wrappers", @cfg[:install]
+    assert_equal "/tmp/gems", @cfg.home
     assert_equal(["/usr/ruby/1.8/lib/ruby/gems/1.8", "/var/ruby/1.8/gem_home"],
                  @cfg.path)
     assert_equal 0, @cfg.ssl_verify_mode
@@ -77,6 +80,7 @@ def test_initialize
     assert_equal 28, @cfg.cert_expiration_length_days
     assert_equal false, @cfg.install_extension_in_lib
     assert_equal true, @cfg.ipv4_fallback_enabled
+    assert_equal true, @cfg.use_psych
   end
 
   def test_initialize_ipv4_fallback_enabled_env
@@ -105,7 +109,7 @@ def test_initialize_global_gem_cache_env
 
   def test_initialize_global_gem_cache_gemrc
     File.open @temp_conf, "w" do |fp|
-      fp.puts "global_gem_cache: true"
+      fp.puts ":global_gem_cache: true"
     end
 
     util_config_file %W[--config-file #{@temp_conf}]
@@ -113,9 +117,19 @@ def test_initialize_global_gem_cache_gemrc
     assert_equal true, @cfg.global_gem_cache
   end
 
+  def test_initialize_use_psych_env
+    orig_use_psych = ENV["RUBYGEMS_USE_PSYCH"]
+    ENV["RUBYGEMS_USE_PSYCH"] = "true"
+    util_config_file %W[--config-file #{@temp_conf}]
+
+    assert_equal true, @cfg.use_psych
+  ensure
+    ENV["RUBYGEMS_USE_PSYCH"] = orig_use_psych
+  end
+
   def test_initialize_concurrent_downloads
     File.open @temp_conf, "w" do |fp|
-      fp.puts "concurrent_downloads: 2"
+      fp.puts ":concurrent_downloads: 2"
     end
 
     util_config_file %W[--config-file #{@temp_conf}]