release: prepare for 0.5.0

CHANGELOG.md

@@ -5,7 +5,7 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
-## [Unreleased]
+## [0.5.0] - 2025-05-06
 
 #### Added
  - New function `secp256k1_ec_pubkey_sort` that sorts public keys using lexicographic (of compressed serialization) order.
@@ -15,6 +15,9 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
    - The related configure option `--ecmult-gen-precision` was replaced with `--ecmult-gen-kb` (`ECMULT_GEN_KB` for CMake).
    - This changes the supported precomputed table sizes for these operations. The new supported sizes are 2 KiB, 22 KiB, or 86 KiB (while the old supported sizes were 32 KiB, 64 KiB, or 512 KiB).
 
+#### ABI Compatibility
+The ABI is backward compatible with versions 0.4.x and 0.3.x.
+
 ## [0.4.1] - 2023-12-21
 
 #### Changed
@@ -123,7 +126,7 @@ 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/v0.4.1...HEAD
+[0.5.0]: https://github.com/bitcoin-core/secp256k1/compare/v0.4.1...v0.5.0
 [0.4.1]: https://github.com/bitcoin-core/secp256k1/compare/v0.4.0...v0.4.1
 [0.4.0]: https://github.com/bitcoin-core/secp256k1/compare/v0.3.2...v0.4.0
 [0.3.2]: https://github.com/bitcoin-core/secp256k1/compare/v0.3.1...v0.3.2