diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 17e82601..f2b38101 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -755,13 +755,13 @@ jobs:
       fail-fast: false
       matrix:
         env_vars:
-          - { WIDEMUL: 'int64',  RECOVERY: 'yes', ECDH: 'yes', EXTRAKEYS: 'yes', SCHNORRSIG: 'yes', ELLSWIFT: 'yes' }
+          - { WIDEMUL: 'int64',  RECOVERY: 'yes', ECDH: 'yes', SCHNORRSIG: 'yes', ELLSWIFT: 'yes', EXPERIMENTAL: 'yes', ECDSA_S2C: 'yes', RANGEPROOF: 'yes', WHITELIST: 'yes', GENERATOR: 'yes', MUSIG: 'yes', ECDSAADAPTOR: 'yes', BPPP: 'yes', SCHNORRSIG_HALFAGG: 'yes' }
           - { WIDEMUL: 'int128_struct', ECMULTGENKB: 2, ECMULTWINDOW: 4 }
-          - { WIDEMUL: 'int128',                  ECDH: 'yes', EXTRAKEYS: 'yes', SCHNORRSIG: 'yes', ELLSWIFT: 'yes' }
+          - { WIDEMUL: 'int128',                  ECDH: 'yes', SCHNORRSIG: 'yes', ELLSWIFT: 'yes', EXPERIMENTAL: 'yes', ECDSA_S2C: 'yes', RANGEPROOF: 'yes', WHITELIST: 'yes', GENERATOR: 'yes', MUSIG: 'yes', ECDSAADAPTOR: 'yes', BPPP: 'yes', SCHNORRSIG_HALFAGG: 'yes' }
           - { WIDEMUL: 'int128', RECOVERY: 'yes' }
-          - { WIDEMUL: 'int128', RECOVERY: 'yes', ECDH: 'yes', EXTRAKEYS: 'yes', SCHNORRSIG: 'yes', ELLSWIFT: 'yes' }
-          - { WIDEMUL: 'int128', RECOVERY: 'yes', ECDH: 'yes', EXTRAKEYS: 'yes', SCHNORRSIG: 'yes', ELLSWIFT: 'yes', CC: 'gcc' }
-          - { WIDEMUL: 'int128', RECOVERY: 'yes', ECDH: 'yes', EXTRAKEYS: 'yes', SCHNORRSIG: 'yes', ELLSWIFT: 'yes', CPPFLAGS: '-DVERIFY' }
+          - { WIDEMUL: 'int128', RECOVERY: 'yes', ECDH: 'yes', SCHNORRSIG: 'yes', ELLSWIFT: 'yes', EXPERIMENTAL: 'yes', ECDSA_S2C: 'yes', RANGEPROOF: 'yes', WHITELIST: 'yes', GENERATOR: 'yes', MUSIG: 'yes', ECDSAADAPTOR: 'yes', BPPP: 'yes', SCHNORRSIG_HALFAGG: 'yes' }
+          - { WIDEMUL: 'int128', RECOVERY: 'yes', ECDH: 'yes', SCHNORRSIG: 'yes', ELLSWIFT: 'yes', EXPERIMENTAL: 'yes', ECDSA_S2C: 'yes', RANGEPROOF: 'yes', WHITELIST: 'yes', GENERATOR: 'yes', MUSIG: 'yes', ECDSAADAPTOR: 'yes', BPPP: 'yes', SCHNORRSIG_HALFAGG: 'yes', CC: 'gcc' }
+          - { WIDEMUL: 'int128', RECOVERY: 'yes', ECDH: 'yes', SCHNORRSIG: 'yes', ELLSWIFT: 'yes', EXPERIMENTAL: 'yes', ECDSA_S2C: 'yes', RANGEPROOF: 'yes', WHITELIST: 'yes', GENERATOR: 'yes', MUSIG: 'yes', ECDSAADAPTOR: 'yes', BPPP: 'yes', SCHNORRSIG_HALFAGG: 'yes', CPPFLAGS: '-DVERIFY' }
           - BUILD: 'distcheck'
 
     steps:
diff --git a/CHANGELOG.md b/CHANGELOG.md
index f889aa77..95ca1b61 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -10,6 +10,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+## [0.5.0] - 2024-05-06
+
 #### Added
  - New function `secp256k1_ec_pubkey_sort` that sorts public keys using lexicographic (of compressed serialization) order.
 
@@ -18,6 +20,9 @@ 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
@@ -126,7 +131,8 @@ 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
+[unreleased]: https://github.com/bitcoin-core/secp256k1/compare/v0.5.0...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
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 56aae705..7f2ad5c6 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -11,7 +11,7 @@ project(libsecp256k1
   # The package (a.k.a. release) version is based on semantic versioning 2.0.0 of
   # the API. All changes in experimental modules are treated as
   # backwards-compatible and therefore at most increase the minor version.
-  VERSION 0.4.2
+  VERSION 0.5.1
   DESCRIPTION "Optimized C library for ECDSA signatures and secret/public key operations on curve secp256k1."
   HOMEPAGE_URL "https://github.com/bitcoin-core/secp256k1"
   LANGUAGES C
@@ -34,9 +34,9 @@ endif()
 # https://www.gnu.org/software/libtool/manual/html_node/Updating-version-info.html
 # All changes in experimental modules are treated as if they don't affect the
 # interface and therefore only increase the revision.
-set(${PROJECT_NAME}_LIB_VERSION_CURRENT 3)
-set(${PROJECT_NAME}_LIB_VERSION_REVISION 2)
-set(${PROJECT_NAME}_LIB_VERSION_AGE 1)
+set(${PROJECT_NAME}_LIB_VERSION_CURRENT 4)
+set(${PROJECT_NAME}_LIB_VERSION_REVISION 1)
+set(${PROJECT_NAME}_LIB_VERSION_AGE 2)
 
 set(CMAKE_C_STANDARD 90)
 set(CMAKE_C_EXTENSIONS OFF)
@@ -325,6 +325,17 @@ endif()
 
 set(CMAKE_C_VISIBILITY_PRESET hidden)
 
+set(print_msan_notice)
+if(SECP256K1_BUILD_CTIME_TESTS)
+  include(CheckMemorySanitizer)
+  check_memory_sanitizer(msan_enabled)
+  if(msan_enabled)
+    try_append_c_flags(-fno-sanitize-memory-param-retval)
+    set(print_msan_notice YES)
+  endif()
+  unset(msan_enabled)
+endif()
+
 # Ask CTest to create a "check" target (e.g., make check) as alias for the "test" target.
 # CTEST_TEST_TARGET_ALIAS is not documented but supposed to be user-facing.
 # See: https://gitlab.kitware.com/cmake/cmake/-/commit/816c9d1aa1f2b42d40c81a991b68c96eb12b6d2
@@ -402,7 +413,7 @@ message("Valgrind .............................. ${SECP256K1_VALGRIND}")
 get_directory_property(definitions COMPILE_DEFINITIONS)
 string(REPLACE ";" " " definitions "${definitions}")
 message("Preprocessor defined macros ........... ${definitions}")
-message("C compiler ............................ ${CMAKE_C_COMPILER}")
+message("C compiler ............................ ${CMAKE_C_COMPILER_ID} ${CMAKE_C_COMPILER_VERSION}, ${CMAKE_C_COMPILER}")
 message("CFLAGS ................................ ${CMAKE_C_FLAGS}")
 get_directory_property(compile_options COMPILE_OPTIONS)
 string(REPLACE ";" " " compile_options "${compile_options}")
@@ -428,7 +439,14 @@ endif()
 if(SECP256K1_LATE_CFLAGS)
   message("SECP256K1_LATE_CFLAGS ................. ${SECP256K1_LATE_CFLAGS}")
 endif()
-message("\n")
+message("")
+if(print_msan_notice)
+  message(
+    "Note:\n"
+    "  MemorySanitizer detected, tried to add -fno-sanitize-memory-param-retval to compile options\n"
+    "  to avoid false positives in ctime_tests. Pass -DSECP256K1_BUILD_CTIME_TESTS=OFF to avoid this.\n"
+  )
+endif()
 if(SECP256K1_EXPERIMENTAL)
   message(
     "  ******\n"
diff --git a/build-aux/m4/bitcoin_secp.m4 b/build-aux/m4/bitcoin_secp.m4
index fee2d7b4..048267fa 100644
--- a/build-aux/m4/bitcoin_secp.m4
+++ b/build-aux/m4/bitcoin_secp.m4
@@ -50,10 +50,14 @@ AC_MSG_CHECKING(whether MemorySanitizer is enabled)
 AC_COMPILE_IFELSE([AC_LANG_SOURCE([[
   #if defined(__has_feature)
   #  if __has_feature(memory_sanitizer)
-  #    error "MemorySanitizer is enabled."
+       /* MemorySanitizer is enabled. */
+  #  elif
+  #    error "MemorySanitizer is disabled."
   #  endif
+  #else
+  #  error "__has_feature is not defined."
   #endif
-  ]])], [msan_enabled=no], [msan_enabled=yes])
+  ]])], [msan_enabled=yes], [msan_enabled=no])
 AC_MSG_RESULT([$msan_enabled])
 ])
 
diff --git a/cmake/CheckArm32Assembly.cmake b/cmake/CheckArm32Assembly.cmake
index 15c44b24..baeeff02 100644
--- a/cmake/CheckArm32Assembly.cmake
+++ b/cmake/CheckArm32Assembly.cmake
@@ -1,6 +1,6 @@
 function(check_arm32_assembly)
   try_compile(HAVE_ARM32_ASM
-    ${CMAKE_BINARY_DIR}/check_arm32_assembly
-    SOURCES ${CMAKE_SOURCE_DIR}/cmake/source_arm32.s
+    ${PROJECT_BINARY_DIR}/check_arm32_assembly
+    SOURCES ${PROJECT_SOURCE_DIR}/cmake/source_arm32.s
   )
 endfunction()
diff --git a/cmake/CheckMemorySanitizer.cmake b/cmake/CheckMemorySanitizer.cmake
new file mode 100644
index 00000000..d9ef681e
--- /dev/null
+++ b/cmake/CheckMemorySanitizer.cmake
@@ -0,0 +1,18 @@
+include_guard(GLOBAL)
+include(CheckCSourceCompiles)
+
+function(check_memory_sanitizer output)
+  set(CMAKE_TRY_COMPILE_TARGET_TYPE STATIC_LIBRARY)
+  check_c_source_compiles("
+    #if defined(__has_feature)
+    #  if __has_feature(memory_sanitizer)
+         /* MemorySanitizer is enabled. */
+    #  elif
+    #    error \"MemorySanitizer is disabled.\"
+    #  endif
+    #else
+    #  error \"__has_feature is not defined.\"
+    #endif
+  " HAVE_MSAN)
+  set(${output} ${HAVE_MSAN} PARENT_SCOPE)
+endfunction()
diff --git a/configure.ac b/configure.ac
index 534929f0..93edd171 100644
--- a/configure.ac
+++ b/configure.ac
@@ -296,7 +296,7 @@ if test x"$enable_ctime_tests" = x"auto"; then
 fi
 
 print_msan_notice=no
-if test x"$enable_ctime_tests" = x"yes" && test x"$GCC" = x"yes"; then
+if test x"$enable_ctime_tests" = x"yes"; then
   SECP_MSAN_CHECK
   # MSan on Clang >=16 reports unitialized memory in function parameters and return values, even if
   # the uninitalized variable is never actually "used". This is called "eager" checking, and it's
diff --git a/src/tests.c b/src/tests.c
index 0d57ab25..8a233808 100644
--- a/src/tests.c
+++ b/src/tests.c
@@ -5671,8 +5671,8 @@ static void test_ecmult_accumulate(secp256k1_sha256* acc, const secp256k1_scalar
     secp256k1_ecmult_gen(&CTX->ecmult_gen_ctx, &rj1, x);
     secp256k1_ecmult(&rj2, &gj, x, &secp256k1_scalar_zero);
     secp256k1_ecmult(&rj3, &infj, &secp256k1_scalar_zero, x);
-    secp256k1_ecmult_multi_var(NULL, scratch, &rj4, x, NULL, NULL, 0);
-    secp256k1_ecmult_multi_var(NULL, scratch, &rj5, &secp256k1_scalar_zero, test_ecmult_accumulate_cb, (void*)x, 1);
+    CHECK(secp256k1_ecmult_multi_var(&CTX->error_callback, scratch, &rj4, x, NULL, NULL, 0));
+    CHECK(secp256k1_ecmult_multi_var(&CTX->error_callback, scratch, &rj5, &secp256k1_scalar_zero, test_ecmult_accumulate_cb, (void*)x, 1));
     secp256k1_ecmult_const(&rj6, &secp256k1_ge_const_g, x);
     secp256k1_ge_set_gej_var(&r, &rj1);
     CHECK(secp256k1_gej_eq_ge_var(&rj2, &r));
diff --git a/tools/check-abi.sh b/tools/check-abi.sh
index 55c945ac..94a98831 100755
--- a/tools/check-abi.sh
+++ b/tools/check-abi.sh
@@ -49,7 +49,7 @@ checkout_and_build() {
         -DSECP256K1_BUILD_CTIME_TESTS=OFF \
         -DSECP256K1_BUILD_EXAMPLES=OFF
     cmake --build . -j "$(nproc)"
-    abi-dumper src/libsecp256k1.so -o ABI.dump -lver "$2"
+    abi-dumper src/libsecp256k1.so -o ABI.dump -lver "$2" -public-headers ../include/
     cd "$_orig_dir"
 }