release: prepare for 0.3.0

CHANGELOG.md

@@ -7,6 +7,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+## [0.3.0] - 2023-03-08
+
 #### Added
  - Added experimental support for CMake builds. Traditional GNU Autotools builds (`./configure` and `make`) remain fully supported.
  - Usage examples: Added a recommended method for securely clearing sensitive data, e.g., secret keys, from memory.
@@ -22,6 +24,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 #### Removed
  - Removed the configuration header `src/libsecp256k1-config.h`. We recommend passing flags to `./configure` or `cmake` to set configuration options (see `./configure --help` or `cmake -LH`). If you cannot or do not want to use one of the supported build systems, pass configuration flags such as `-DSECP256K1_ENABLE_MODULE_SCHNORRSIG` manually to the compiler (see the file `configure.ac` for supported flags).
 
+#### ABI Compatibility
+
+Due to changes in the API regarding `secp256k1_context_static` described above, the ABI is *not* compatible with previous versions.
+
 ## [0.2.0] - 2022-12-12
 
 #### Added
@@ -49,6 +55,7 @@ This version was in fact never released.
 The number was given by the build system since the introduction of autotools in Jan 2014 (ea0fe5a5bf0c04f9cc955b2966b614f5f378c6f6).
 Therefore, this version number does not uniquely identify a set of source files.
 
-[unreleased]: https://github.com/bitcoin-core/secp256k1/compare/v0.2.0...HEAD
+[unreleased]: https://github.com/bitcoin-core/secp256k1/compare/v0.3.0...HEAD
+[0.3.0]: https://github.com/bitcoin-core/secp256k1/compare/v0.2.0...v0.3.0
 [0.2.0]: https://github.com/bitcoin-core/secp256k1/compare/423b6d19d373f1224fd671a982584d7e7900bc93..v0.2.0
 [0.1.0]: https://github.com/bitcoin-core/secp256k1/commit/423b6d19d373f1224fd671a982584d7e7900bc93