docs(release): update changelog for the 2026-04 release (#16074)

Author: scotthart

CHANGELOG.md

@@ -7,17 +7,35 @@ breaking changes in the upcoming 4.x release. This release is scheduled for
 **NOTE**: Please refer to the [V3 Migration Guide](/doc/v3-migration-guide.md) 
 for details on updating existing applications using v1.x.y or v2.x.y.
 
-## v3.4.0 - TBD
+## v3.4.0 - 2026-04
+
+### [Bigtable](/google/cloud/bigtable/README.md)
+
+- Dynamic Channel Pool support has been added as an opt-in feature. It can be
+  enabled via the [InstanceChannelAffinityOption](https://github.com/googleapis/google-cloud-cpp/blob/f3de489be4caaaf17e589c7fd7e427488c474f61/google/cloud/bigtable/options.h#L186)
+  and configured via the [DynamicChannelPoolSizingPolicyOption](https://github.com/googleapis/google-cloud-cpp/blob/f3de489be4caaaf17e589c7fd7e427488c474f61/google/cloud/bigtable/options.h#L222).
 
 ### [Data Catalog](/google/cloud/datacatalog/README.md)
 
-- Added Data Lineage Config Management library.
+- Added Data Lineage Config Management library.([#16069](https://github.com/googleapis/google-cloud-cpp/pull/16069))
 
 ### [Dataplex](/google/cloud/dataplex/README.md)
 
-- Added Business Glossary library.
-- Added CMEK library.
-- Added Data Products library.
+- Added Business Glossary library.([#16072](https://github.com/googleapis/google-cloud-cpp/pull/16072))
+- Added CMEK library.([#16072](https://github.com/googleapis/google-cloud-cpp/pull/16072))
+- Added Data Products library.([#16072](https://github.com/googleapis/google-cloud-cpp/pull/16072))
+
+### [Spanner](/google/cloud/spanner/README.md)
+
+- feat(spanner): set read lock mode at client level ([#16068](https://github.com/googleapis/google-cloud-cpp/pull/16068))
+
+### [Storage](/google/cloud/storage/README.md)
+
+- feat(storage): add IsOpen API for zonal read operation ([#16063](https://github.com/googleapis/google-cloud-cpp/pull/16063))
+
+### [Google APIs interface definitions](https://github.com/googleapis/googleapis)
+
+- This release is based on definitions as of [2026-04-02T09:44:56-07:00](https://github.com/googleapis/googleapis/tree/c8ca5bce5cbabac76b8619bd8d63ac10bb0561a9)
 
 ## v3.3.0 - 2026-03
 

CMakeLists.txt

@@ -23,7 +23,7 @@ project(
     google-cloud-cpp
     VERSION 3.4.0
     LANGUAGES CXX)
-set(PROJECT_VERSION_PRE_RELEASE "rc")
+set(PROJECT_VERSION_PRE_RELEASE "")
 
 if (NOT "${PROJECT_VERSION_PRE_RELEASE}" STREQUAL "")
     set(PROJECT_VERSION "${PROJECT_VERSION}-${PROJECT_VERSION_PRE_RELEASE}")

MODULE.bazel

@@ -16,7 +16,7 @@
 
 module(
     name = "google_cloud_cpp",
-    version = "3.4.0-rc",  # Updated by CMake
+    version = "3.4.0",  # Updated by CMake
     compatibility_level = 3,  # Updated by CMake
 )
 

google/cloud/internal/version_info.h

@@ -21,6 +21,6 @@
 #define GOOGLE_CLOUD_CPP_VERSION_MINOR 4
 // NOLINTNEXTLINE(modernize-macro-to-enum)
 #define GOOGLE_CLOUD_CPP_VERSION_PATCH 0
-#define GOOGLE_CLOUD_CPP_VERSION_PRE_RELEASE "rc"
+#define GOOGLE_CLOUD_CPP_VERSION_PRE_RELEASE ""
 
 #endif  // GOOGLE_CLOUD_CPP_GOOGLE_CLOUD_INTERNAL_VERSION_INFO_H