Merge branch '3.20.x' into 3.20.x-202204011233
diff --git a/CHANGES.txt b/CHANGES.txt
index 71b4927..873c0dc 100644
--- a/CHANGES.txt
+++ b/CHANGES.txt
@@ -17,8 +17,11 @@
 
   Ruby
   * Dropped Ruby 2.3 and 2.4 support for CI and releases. (#9311)
-  * Message.decode/encode: Add max_recursion_depth option (#9218)
-  * Rename max_recursion_depth to recursion_limit (#9486)
+  * Added Ruby 3.1 support for CI and releases (#9566).
+  * Message.decode/encode: Add recursion_limit option (#9218/#9486)
+  * Allocate with xrealloc()/xfree() so message allocation is visible to the
+    Ruby GC.  In certain tests this leads to much lower memory usage due to more
+    frequent GC runs (#9586).
   * Fix conversion of singleton classes in Ruby (#9342)
   * Suppress warning for intentional circular require (#9556)
   * JSON will now output shorter strings for double and float fields when possible
diff --git a/Protobuf-C++.podspec b/Protobuf-C++.podspec
index cc331e3..afc0743 100644
--- a/Protobuf-C++.podspec
+++ b/Protobuf-C++.podspec
@@ -1,6 +1,6 @@
 Pod::Spec.new do |s|
   s.name     = 'Protobuf-C++'
-  s.version  = '3.20.0-rc1'
+  s.version  = '3.20.0'
   s.summary  = 'Protocol Buffers v3 runtime library for C++.'
   s.homepage = 'https://github.com/google/protobuf'
   s.license  = 'BSD-3-Clause'
diff --git a/Protobuf.podspec b/Protobuf.podspec
index 3bd7147..92c53c9 100644
--- a/Protobuf.podspec
+++ b/Protobuf.podspec
@@ -5,7 +5,7 @@
 # dependent projects use the :git notation to refer to the library.
 Pod::Spec.new do |s|
   s.name     = 'Protobuf'
-  s.version  = '3.20.0-rc1'
+  s.version  = '3.20.0'
   s.summary  = 'Protocol Buffers v.3 runtime library for Objective-C.'
   s.homepage = 'https://github.com/protocolbuffers/protobuf'
   s.license  = 'BSD-3-Clause'
diff --git a/configure.ac b/configure.ac
index 2b1cdad..4db50ce 100644
--- a/configure.ac
+++ b/configure.ac
@@ -17,7 +17,7 @@
 # In the SVN trunk, the version should always be the next anticipated release
 # version with the "-pre" suffix.  (We used to use "-SNAPSHOT" but this pushed
 # the size of one file name in the dist tarfile over the 99-char limit.)
-AC_INIT([Protocol Buffers],[3.20.0-rc-1],[protobuf@googlegroups.com],[protobuf])
+AC_INIT([Protocol Buffers],[3.20.0],[protobuf@googlegroups.com],[protobuf])
 
 AM_MAINTAINER_MODE([enable])
 
diff --git a/csharp/Google.Protobuf.Tools.nuspec b/csharp/Google.Protobuf.Tools.nuspec
index 86f12c9..21b6a62 100644
--- a/csharp/Google.Protobuf.Tools.nuspec
+++ b/csharp/Google.Protobuf.Tools.nuspec
@@ -5,7 +5,7 @@
     <title>Google Protocol Buffers tools</title>
     <summary>Tools for Protocol Buffers - Google's data interchange format.</summary>
     <description>See project site for more info.</description>
-    <version>3.20.0-rc1</version>
+    <version>3.20.0</version>
     <authors>Google Inc.</authors>
     <owners>protobuf-packages</owners>
     <licenseUrl>https://github.com/protocolbuffers/protobuf/blob/master/LICENSE</licenseUrl>
diff --git a/csharp/src/Google.Protobuf/Google.Protobuf.csproj b/csharp/src/Google.Protobuf/Google.Protobuf.csproj
index db5329e..22253cb 100644
--- a/csharp/src/Google.Protobuf/Google.Protobuf.csproj
+++ b/csharp/src/Google.Protobuf/Google.Protobuf.csproj
@@ -4,7 +4,7 @@
     <Description>C# runtime library for Protocol Buffers - Google's data interchange format.</Description>
     <Copyright>Copyright 2015, Google Inc.</Copyright>
     <AssemblyTitle>Google Protocol Buffers</AssemblyTitle>
-    <VersionPrefix>3.20.0-rc1</VersionPrefix>
+    <VersionPrefix>3.20.0</VersionPrefix>
     <!-- C# 7.2 is required for Span/BufferWriter/ReadOnlySequence -->
     <LangVersion>7.2</LangVersion>
     <Authors>Google Inc.</Authors>
diff --git a/java/README.md b/java/README.md
index ecbb9a6..df68050 100644
--- a/java/README.md
+++ b/java/README.md
@@ -23,7 +23,7 @@
 <dependency>
   <groupId>com.google.protobuf</groupId>
   <artifactId>protobuf-java</artifactId>
-  <version>3.20.0-rc-1</version>
+  <version>3.20.0</version>
 </dependency>
 ```
 
@@ -37,7 +37,7 @@
 <dependency>
   <groupId>com.google.protobuf</groupId>
   <artifactId>protobuf-java-util</artifactId>
-  <version>3.20.0-rc-1</version>
+  <version>3.20.0</version>
 </dependency>
 ```
 
@@ -45,7 +45,7 @@
 
 If you are using Gradle, add the following to your `build.gradle` file's dependencies:
 ```
-    implementation 'com.google.protobuf:protobuf-java:3.20.0-rc-1'
+    implementation 'com.google.protobuf:protobuf-java:3.20.0'
 ```
 Again, be sure to check that the version number matches (or is newer than) the version number of protoc that you are using.
 
diff --git a/java/bom/pom.xml b/java/bom/pom.xml
index c5bcb0a..5ebf16a 100644
--- a/java/bom/pom.xml
+++ b/java/bom/pom.xml
@@ -4,7 +4,7 @@
 
   <groupId>com.google.protobuf</groupId>
   <artifactId>protobuf-bom</artifactId>
-  <version>3.20.0-rc-1</version>
+  <version>3.20.0</version>
   <packaging>pom</packaging>
 
   <name>Protocol Buffers [BOM]</name>
diff --git a/java/core/pom.xml b/java/core/pom.xml
index bce2b11..9dadd70 100644
--- a/java/core/pom.xml
+++ b/java/core/pom.xml
@@ -4,7 +4,7 @@
   <parent>
     <groupId>com.google.protobuf</groupId>
     <artifactId>protobuf-parent</artifactId>
-    <version>3.20.0-rc-1</version>
+    <version>3.20.0</version>
   </parent>
 
   <artifactId>protobuf-java</artifactId>
diff --git a/java/kotlin-lite/pom.xml b/java/kotlin-lite/pom.xml
index 6ccb100..11a0102 100644
--- a/java/kotlin-lite/pom.xml
+++ b/java/kotlin-lite/pom.xml
@@ -4,7 +4,7 @@
   <parent>
     <groupId>com.google.protobuf</groupId>
     <artifactId>protobuf-parent</artifactId>
-    <version>3.20.0-rc-1</version>
+    <version>3.20.0</version>
   </parent>
 
   <artifactId>protobuf-kotlin-lite</artifactId>
diff --git a/java/kotlin/pom.xml b/java/kotlin/pom.xml
index 2ae5b68..fe9e0e5 100644
--- a/java/kotlin/pom.xml
+++ b/java/kotlin/pom.xml
@@ -4,7 +4,7 @@
   <parent>
     <groupId>com.google.protobuf</groupId>
     <artifactId>protobuf-parent</artifactId>
-    <version>3.20.0-rc-1</version>
+    <version>3.20.0</version>
   </parent>
 
   <artifactId>protobuf-kotlin</artifactId>
diff --git a/java/lite.md b/java/lite.md
index a71d48e..6fab856 100644
--- a/java/lite.md
+++ b/java/lite.md
@@ -29,7 +29,7 @@
 <dependency>
   <groupId>com.google.protobuf</groupId>
   <artifactId>protobuf-javalite</artifactId>
-  <version>3.20.0-rc-1</version>
+  <version>3.20.0</version>
 </dependency>
 ```
 
diff --git a/java/lite/pom.xml b/java/lite/pom.xml
index 35d8ac2..c2f7e37 100644
--- a/java/lite/pom.xml
+++ b/java/lite/pom.xml
@@ -4,7 +4,7 @@
   <parent>
     <groupId>com.google.protobuf</groupId>
     <artifactId>protobuf-parent</artifactId>
-    <version>3.20.0-rc-1</version>
+    <version>3.20.0</version>
   </parent>
 
   <artifactId>protobuf-javalite</artifactId>
diff --git a/java/pom.xml b/java/pom.xml
index 4869c94..82f31fb 100644
--- a/java/pom.xml
+++ b/java/pom.xml
@@ -4,7 +4,7 @@
 
   <groupId>com.google.protobuf</groupId>
   <artifactId>protobuf-parent</artifactId>
-  <version>3.20.0-rc-1</version>
+  <version>3.20.0</version>
   <packaging>pom</packaging>
 
   <name>Protocol Buffers [Parent]</name>
diff --git a/java/util/pom.xml b/java/util/pom.xml
index 34fcbb3..d9eadd6 100644
--- a/java/util/pom.xml
+++ b/java/util/pom.xml
@@ -4,7 +4,7 @@
   <parent>
     <groupId>com.google.protobuf</groupId>
     <artifactId>protobuf-parent</artifactId>
-    <version>3.20.0-rc-1</version>
+    <version>3.20.0</version>
   </parent>
 
   <artifactId>protobuf-java-util</artifactId>
diff --git a/js/package.json b/js/package.json
index 3f7e291..e5c9a60 100644
--- a/js/package.json
+++ b/js/package.json
@@ -1,6 +1,6 @@
 {
   "name": "google-protobuf",
-  "version": "3.20.0-rc.1",
+  "version": "3.20.0",
   "description": "Protocol Buffers for JavaScript",
   "main": "google-protobuf.js",
   "files": [
diff --git a/php/ext/google/protobuf/package.xml b/php/ext/google/protobuf/package.xml
index 44c4815..b529dc9 100644
--- a/php/ext/google/protobuf/package.xml
+++ b/php/ext/google/protobuf/package.xml
@@ -10,15 +10,15 @@
   <email>protobuf-opensource@google.com</email>
   <active>yes</active>
  </lead>
- <date>2022-03-04</date>
- <time>16:28:14</time>
+ <date>2022-03-25</date>
+ <time>19:17:44</time>
  <version>
-  <release>3.20.0RC1</release>
+  <release>3.20.0</release>
   <api>3.20.0</api>
  </version>
  <stability>
-  <release>beta</release>
-  <api>beta</api>
+  <release>stable</release>
+  <api>stable</api>
  </stability>
  <license uri="https://opensource.org/licenses/BSD-3-Clause">BSD-3-Clause</license>
  <notes>
@@ -46,10 +46,12 @@
     <file baseinstalldir="/" name="protobuf.c" role="src"/>
     <file baseinstalldir="/" name="protobuf.h" role="src"/>
     <file baseinstalldir="/" name="wkt.inc" role="src"/>
-    <file baseinstalldir="/" name="third_party/utf8_range/naive.c" role="doc"/>
-    <file baseinstalldir="/" name="third_party/utf8_range/range2-neon.c" role="doc"/>
-    <file baseinstalldir="/" name="third_party/utf8_range/range2-sse.c" role="doc"/>
     <file baseinstalldir="/" name="LICENSE" role="doc"/>
+    <file baseinstalldir="/" name="third_party/utf8_range/naive.c" role="src"/>
+    <file baseinstalldir="/" name="third_party/utf8_range/range2-neon.c" role="src"/>
+    <file baseinstalldir="/" name="third_party/utf8_range/range2-sse.c" role="src"/>
+    <file baseinstalldir="/" name="third_party/utf8_range/utf8_range.h" role="src"/>
+    <file baseinstalldir="/" name="third_party/utf8_range/LICENSE" role="doc"/>
   </dir>
  </contents>
  <dependencies>
@@ -1221,5 +1223,35 @@
    <notes>
    </notes>
   </release>
+  <release>
+   <version>
+    <release>3.20.0RC2</release>
+    <api>3.20.0</api>
+   </version>
+   <stability>
+    <release>beta</release>
+    <api>beta</api>
+   </stability>
+   <date>2022-03-15</date>
+   <time>21:10:15</time>
+   <license uri="https://opensource.org/licenses/BSD-3-Clause">BSD-3-Clause</license>
+   <notes>
+   </notes>
+  </release>
+  <release>
+   <version>
+    <release>3.20.0</release>
+    <api>3.20.0</api>
+   </version>
+   <stability>
+    <release>stable</release>
+    <api>stable</api>
+   </stability>
+   <date>2022-03-25</date>
+   <time>19:17:44</time>
+   <license uri="https://opensource.org/licenses/BSD-3-Clause">BSD-3-Clause</license>
+   <notes>
+   </notes>
+  </release>
  </changelog>
 </package>
diff --git a/php/ext/google/protobuf/protobuf.h b/php/ext/google/protobuf/protobuf.h
index 47e2494..01be62a 100644
--- a/php/ext/google/protobuf/protobuf.h
+++ b/php/ext/google/protobuf/protobuf.h
@@ -127,7 +127,7 @@
   ZEND_ARG_INFO(0, value)
 ZEND_END_ARG_INFO()
 
-#define PHP_PROTOBUF_VERSION "3.20.0RC1"
+#define PHP_PROTOBUF_VERSION "3.20.0"
 
 // ptr -> PHP object cache. This is a weak map that caches lazily-created
 // wrapper objects around upb types:
diff --git a/php/release.sh b/php/release.sh
index 6b0baac..9a4b139 100755
--- a/php/release.sh
+++ b/php/release.sh
@@ -30,7 +30,11 @@
 sed -i 's|php/src|src|g' composer.json
 git add .
 git commit -m "$VERSION"
-git tag "$VERSION"
+if [ $(git tag -l "$VERSION") ]; then
+  echo "tag $VERSION already exists"
+else
+  git tag "$VERSION"
+fi
 popd
 
 # Clean up
diff --git a/protobuf.bzl b/protobuf.bzl
index ffd7c8d..8e173fd 100644
--- a/protobuf.bzl
+++ b/protobuf.bzl
@@ -266,9 +266,9 @@
         deps = [],
         cc_libs = [],
         include = None,
-        protoc = Label("//:protoc"),
+        protoc = "@com_google_protobuf//:protoc",
         use_grpc_plugin = False,
-        default_runtime = Label("//:protobuf"),
+        default_runtime = "@com_google_protobuf//:protobuf",
         **kargs):
     """Bazel rule to create a C++ protobuf library from proto source files
 
@@ -386,7 +386,7 @@
         "_protoc": attr.label(
             executable = True,
             cfg = "exec",
-            default = "//:protoc",
+            default = "@com_google_protobuf//:protoc",
         ),
     },
 )
@@ -493,8 +493,8 @@
         py_libs = [],
         py_extra_srcs = [],
         include = None,
-        default_runtime = Label("//:protobuf_python"),
-        protoc = Label("//:protoc"),
+        default_runtime = "@com_google_protobuf//:protobuf_python",
+        protoc = "@com_google_protobuf//:protoc",
         use_grpc_plugin = False,
         **kargs):
     """Bazel rule to create a Python protobuf library from proto source files
diff --git a/protobuf_deps.bzl b/protobuf_deps.bzl
index e87b704..601e6c0 100644
--- a/protobuf_deps.bzl
+++ b/protobuf_deps.bzl
@@ -30,7 +30,7 @@
     if not native.existing_rule("zlib"):
         http_archive(
             name = "zlib",
-            build_file = Label("//:third_party/zlib.BUILD"),
+            build_file = "@com_google_protobuf//:third_party/zlib.BUILD",
             sha256 = "629380c90a77b964d896ed37163f5c3a34f6e6d897311f1df2a7016355c45eff",
             strip_prefix = "zlib-1.2.11",
             urls = ["https://github.com/madler/zlib/archive/v1.2.11.tar.gz"],
diff --git a/protobuf_version.bzl b/protobuf_version.bzl
index b2e158d..a62513f 100644
--- a/protobuf_version.bzl
+++ b/protobuf_version.bzl
@@ -1 +1 @@
-PROTOBUF_VERSION = '3.20.0-rc-1'
+PROTOBUF_VERSION = '3.20.0'
diff --git a/protoc-artifacts/pom.xml b/protoc-artifacts/pom.xml
index 5df1af0..a667c52 100644
--- a/protoc-artifacts/pom.xml
+++ b/protoc-artifacts/pom.xml
@@ -8,7 +8,7 @@
   </parent>
   <groupId>com.google.protobuf</groupId>
   <artifactId>protoc</artifactId>
-  <version>3.20.0-rc-1</version>
+  <version>3.20.0</version>
   <packaging>pom</packaging>
   <name>Protobuf Compiler</name>
   <description>
diff --git a/python/google/protobuf/__init__.py b/python/google/protobuf/__init__.py
index b97fe71..39555e6 100644
--- a/python/google/protobuf/__init__.py
+++ b/python/google/protobuf/__init__.py
@@ -30,4 +30,4 @@
 
 # Copyright 2007 Google Inc. All Rights Reserved.
 
-__version__ = '3.20.0rc1'
+__version__ = '3.20.0'
diff --git a/ruby/google-protobuf.gemspec b/ruby/google-protobuf.gemspec
index 0904700..fa99970 100644
--- a/ruby/google-protobuf.gemspec
+++ b/ruby/google-protobuf.gemspec
@@ -1,6 +1,6 @@
 Gem::Specification.new do |s|
   s.name        = "google-protobuf"
-  s.version     = "3.20.0.rc.1"
+  s.version     = "3.20.0"
   git_tag       = "v#{s.version.to_s.sub('.rc.', '-rc')}" # Converts X.Y.Z.rc.N to vX.Y.Z-rcN, used for the git tag
   s.licenses    = ["BSD-3-Clause"]
   s.summary     = "Protocol Buffers"
diff --git a/ruby/pom.xml b/ruby/pom.xml
index bf6a8c9..5482c6f 100644
--- a/ruby/pom.xml
+++ b/ruby/pom.xml
@@ -9,7 +9,7 @@
 
     <groupId>com.google.protobuf.jruby</groupId>
     <artifactId>protobuf-jruby</artifactId>
-    <version>3.20.0-rc-1</version>
+    <version>3.20.0</version>
     <name>Protocol Buffer JRuby native extension</name>
     <description>
       Protocol Buffers are a way of encoding structured data in an efficient yet
@@ -76,7 +76,7 @@
         <dependency>
           <groupId>com.google.protobuf</groupId>
           <artifactId>protobuf-java-util</artifactId>
-          <version>3.20.0-rc-1</version>
+          <version>3.20.0</version>
         </dependency>
         <dependency>
             <groupId>org.jruby</groupId>
diff --git a/src/google/protobuf/port_def.inc b/src/google/protobuf/port_def.inc
index 2afc7b4..a30c246 100644
--- a/src/google/protobuf/port_def.inc
+++ b/src/google/protobuf/port_def.inc
@@ -172,7 +172,7 @@
 #ifdef PROTOBUF_VERSION_SUFFIX
 #error PROTOBUF_VERSION_SUFFIX was previously defined
 #endif
-#define PROTOBUF_VERSION_SUFFIX "-rc1"
+#define PROTOBUF_VERSION_SUFFIX ""
 
 #if defined(PROTOBUF_NAMESPACE) || defined(PROTOBUF_NAMESPACE_ID)
 #error PROTOBUF_NAMESPACE or PROTOBUF_NAMESPACE_ID was previously defined
diff --git a/src/google/protobuf/stubs/common.h b/src/google/protobuf/stubs/common.h
index fd23dac..f88ab44 100644
--- a/src/google/protobuf/stubs/common.h
+++ b/src/google/protobuf/stubs/common.h
@@ -85,7 +85,7 @@
 #define GOOGLE_PROTOBUF_VERSION 3020000
 
 // A suffix string for alpha, beta or rc releases. Empty for stable releases.
-#define GOOGLE_PROTOBUF_VERSION_SUFFIX "-rc1"
+#define GOOGLE_PROTOBUF_VERSION_SUFFIX ""
 
 // The minimum header version which works with the current version of
 // the library.  This constant should only be used by protoc's C++ code
diff --git a/update_version.py b/update_version.py
index 3a96991..e1f259e 100755
--- a/update_version.py
+++ b/update_version.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 # Usage: ./update_version.py <MAJOR>.<MINOR>.<MICRO> [<RC version>]
 #
 # Example:
@@ -201,7 +201,7 @@
         '#if %s < PROTOBUF_MIN_PROTOC_VERSION' % cpp_version,
         line)
     return line
-    
+
   RewriteTextFile('src/google/protobuf/stubs/common.h', RewriteCommon)
   RewriteTextFile('src/google/protobuf/port_def.inc', RewritePortDef)
   RewriteTextFile('src/google/protobuf/any.pb.h', RewritePbH)
@@ -268,7 +268,7 @@
   RewriteXml('protoc-artifacts/pom.xml',
     lambda document : ReplaceText(
       Find(document.documentElement, 'version'), GetFullVersion()))
-  
+
   RewriteTextFile('java/README.md',
     lambda line : re.sub(
       r'<version>.*</version>',