From cae9a7ad149d359c061372107d212cdcfad5d323 Mon Sep 17 00:00:00 2001
From: Hennadii Stepanov <32963518+hebasto@users.noreply.github.com>
Date: Sat, 11 May 2024 11:05:12 +0100
Subject: [PATCH 01/19] cmake: Do not set emulated PROJECT_IS_TOP_LEVEL as
 cache variable

Otherwise, downstream projects, which integrate the libsecp256k1 library
using the `add_subdirectory()` command, will be affected.
---
 CMakeLists.txt | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 88994d82..27d6e643 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -18,13 +18,14 @@ project(libsecp256k1
 )
 
 if(CMAKE_VERSION VERSION_LESS 3.21)
+  # Emulates CMake 3.21+ behavior.
   get_directory_property(parent_directory PARENT_DIRECTORY)
   if(parent_directory)
-    set(PROJECT_IS_TOP_LEVEL OFF CACHE INTERNAL "Emulates CMake 3.21+ behavior.")
-    set(${PROJECT_NAME}_IS_TOP_LEVEL OFF CACHE INTERNAL "Emulates CMake 3.21+ behavior.")
+    set(PROJECT_IS_TOP_LEVEL OFF)
+    set(${PROJECT_NAME}_IS_TOP_LEVEL OFF)
   else()
-    set(PROJECT_IS_TOP_LEVEL ON CACHE INTERNAL "Emulates CMake 3.21+ behavior.")
-    set(${PROJECT_NAME}_IS_TOP_LEVEL ON CACHE INTERNAL "Emulates CMake 3.21+ behavior.")
+    set(PROJECT_IS_TOP_LEVEL ON)
+    set(${PROJECT_NAME}_IS_TOP_LEVEL ON)
   endif()
   unset(parent_directory)
 endif()

From ec4c002faa350f02919fe0f710279d2922e254a1 Mon Sep 17 00:00:00 2001
From: Hennadii Stepanov <32963518+hebasto@users.noreply.github.com>
Date: Sat, 11 May 2024 11:13:41 +0100
Subject: [PATCH 02/19] cmake: Simplify `PROJECT_IS_TOP_LEVEL` emulation

Detecting whether it is the top level by comparing the value of
`CMAKE_SOURCE_DIR` with `CMAKE_CURRENT_SOURCE_DIR` is supported by all
versions of CMake and is a very common pattern.
---
 CMakeLists.txt | 10 ++++------
 1 file changed, 4 insertions(+), 6 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 27d6e643..fffa123d 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -19,15 +19,13 @@ project(libsecp256k1
 
 if(CMAKE_VERSION VERSION_LESS 3.21)
   # Emulates CMake 3.21+ behavior.
-  get_directory_property(parent_directory PARENT_DIRECTORY)
-  if(parent_directory)
-    set(PROJECT_IS_TOP_LEVEL OFF)
-    set(${PROJECT_NAME}_IS_TOP_LEVEL OFF)
-  else()
+  if(CMAKE_SOURCE_DIR STREQUAL CMAKE_CURRENT_SOURCE_DIR)
     set(PROJECT_IS_TOP_LEVEL ON)
     set(${PROJECT_NAME}_IS_TOP_LEVEL ON)
+  else()
+    set(PROJECT_IS_TOP_LEVEL OFF)
+    set(${PROJECT_NAME}_IS_TOP_LEVEL OFF)
   endif()
-  unset(parent_directory)
 endif()
 
 # The library version is based on libtool versioning of the ABI. The set of

From 122dbaeb371cf65b8ebbc713bcbdb05203670d49 Mon Sep 17 00:00:00 2001
From: Hennadii Stepanov <32963518+hebasto@users.noreply.github.com>
Date: Mon, 27 May 2024 10:56:37 +0100
Subject: [PATCH 03/19] autotools: Remove "auto" value of
 `--with-ecmult-window` option

"auto" implies that a value is being chosen based on build system
introspection or host system capabilities. However, for the
`--with-ecmult-window` option, the value "auto" is hardcoded, which
might lead to confusion.

This change replaces "auto" with a more appropriate default value.
---
 .cirrus.yml              |  2 +-
 .github/workflows/ci.yml |  2 +-
 configure.ac             | 15 ++++-----------
 3 files changed, 6 insertions(+), 13 deletions(-)

diff --git a/.cirrus.yml b/.cirrus.yml
index 6e77403b..6431465d 100644
--- a/.cirrus.yml
+++ b/.cirrus.yml
@@ -10,7 +10,7 @@ env:
   MAKEFLAGS: -j4
   BUILD: check
   ### secp256k1 config
-  ECMULTWINDOW: auto
+  ECMULTWINDOW: 15
   ECMULTGENKB: auto
   ASM: no
   WIDEMUL: auto
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index d2466820..f42f7852 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -21,7 +21,7 @@ env:
   MAKEFLAGS: '-j4'
   BUILD: 'check'
   ### secp256k1 config
-  ECMULTWINDOW: 'auto'
+  ECMULTWINDOW: 15
   ECMULTGENKB: 'auto'
   ASM: 'no'
   WIDEMUL: 'auto'
diff --git a/configure.ac b/configure.ac
index 8b62e1db..c0f809e7 100644
--- a/configure.ac
+++ b/configure.ac
@@ -203,15 +203,15 @@ AC_ARG_WITH([test-override-wide-multiply], [] ,[set_widemul=$withval], [set_wide
 AC_ARG_WITH([asm], [AS_HELP_STRING([--with-asm=x86_64|arm32|no|auto],
 [assembly to use (experimental: arm32) [default=auto]])],[req_asm=$withval], [req_asm=auto])
 
-AC_ARG_WITH([ecmult-window], [AS_HELP_STRING([--with-ecmult-window=SIZE|auto],
+AC_ARG_WITH([ecmult-window], [AS_HELP_STRING([--with-ecmult-window=SIZE],
 [window size for ecmult precomputation for verification, specified as integer in range [2..24].]
 [Larger values result in possibly better performance at the cost of an exponentially larger precomputed table.]
 [The table will store 2^(SIZE-1) * 64 bytes of data but can be larger in memory due to platform-specific padding and alignment.]
 [A window size larger than 15 will require you delete the prebuilt precomputed_ecmult.c file so that it can be rebuilt.]
 [For very large window sizes, use "make -j 1" to reduce memory use during compilation.]
-["auto" is a reasonable setting for desktop machines (currently 15). [default=auto]]
+[The default value is a reasonable setting for desktop machines (currently 15). [default=15]]
 )],
-[req_ecmult_window=$withval], [req_ecmult_window=auto])
+[set_ecmult_window=$withval], [set_ecmult_window=15])
 
 AC_ARG_WITH([ecmult-gen-kb], [AS_HELP_STRING([--with-ecmult-gen-kb=2|22|86|auto],
 [The size of the precomputed table for signing in multiples of 1024 bytes (on typical platforms).]
@@ -335,14 +335,7 @@ auto)
   ;;
 esac
 
-# Set ecmult window size
-if test x"$req_ecmult_window" = x"auto"; then
-  set_ecmult_window=15
-else
-  set_ecmult_window=$req_ecmult_window
-fi
-
-error_window_size=['window size for ecmult precomputation not an integer in range [2..24] or "auto"']
+error_window_size=['window size for ecmult precomputation not an integer in range [2..24]']
 case $set_ecmult_window in
 ''|*[[!0-9]]*)
   # no valid integer

From 26b94ee92a7928d0e3ceb265f8e4b5bbabf01a77 Mon Sep 17 00:00:00 2001
From: Hennadii Stepanov <32963518+hebasto@users.noreply.github.com>
Date: Mon, 27 May 2024 10:46:36 +0100
Subject: [PATCH 04/19] autotools: Remove "auto" value of
 `--with-ecmult-gen-kb` option

"auto" implies that a value is being chosen based on build system
introspection or host system capabilities. However, for the
`--with-ecmult-gen-kb` option, the value "auto" is hardcoded, which
might lead to confusion.

This change replaces "auto" with a more appropriate default value.
---
 .cirrus.yml              |  2 +-
 .github/workflows/ci.yml |  2 +-
 configure.ac             | 15 ++++-----------
 3 files changed, 6 insertions(+), 13 deletions(-)

diff --git a/.cirrus.yml b/.cirrus.yml
index 6431465d..4bd15511 100644
--- a/.cirrus.yml
+++ b/.cirrus.yml
@@ -11,7 +11,7 @@ env:
   BUILD: check
   ### secp256k1 config
   ECMULTWINDOW: 15
-  ECMULTGENKB: auto
+  ECMULTGENKB: 22
   ASM: no
   WIDEMUL: auto
   WITH_VALGRIND: yes
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index f42f7852..98f5e2b3 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -22,7 +22,7 @@ env:
   BUILD: 'check'
   ### secp256k1 config
   ECMULTWINDOW: 15
-  ECMULTGENKB: 'auto'
+  ECMULTGENKB: 22
   ASM: 'no'
   WIDEMUL: 'auto'
   WITH_VALGRIND: 'yes'
diff --git a/configure.ac b/configure.ac
index c0f809e7..ed3c4b80 100644
--- a/configure.ac
+++ b/configure.ac
@@ -213,12 +213,12 @@ AC_ARG_WITH([ecmult-window], [AS_HELP_STRING([--with-ecmult-window=SIZE],
 )],
 [set_ecmult_window=$withval], [set_ecmult_window=15])
 
-AC_ARG_WITH([ecmult-gen-kb], [AS_HELP_STRING([--with-ecmult-gen-kb=2|22|86|auto],
+AC_ARG_WITH([ecmult-gen-kb], [AS_HELP_STRING([--with-ecmult-gen-kb=2|22|86],
 [The size of the precomputed table for signing in multiples of 1024 bytes (on typical platforms).]
 [Larger values result in possibly better signing/keygeneration performance at the cost of a larger table.]
-["auto" is a reasonable setting for desktop machines (currently 22). [default=auto]]
+[The default value is a reasonable setting for desktop machines (currently 22). [default=22]]
 )],
-[req_ecmult_gen_kb=$withval], [req_ecmult_gen_kb=auto])
+[set_ecmult_gen_kb=$withval], [set_ecmult_gen_kb=22])
 
 AC_ARG_WITH([valgrind], [AS_HELP_STRING([--with-valgrind=yes|no|auto],
 [Build with extra checks for running inside Valgrind [default=auto]]
@@ -350,13 +350,6 @@ case $set_ecmult_window in
   ;;
 esac
 
-# Set ecmult gen kb
-if test x"$req_ecmult_gen_kb" = x"auto"; then
-  set_ecmult_gen_kb=22
-else
-  set_ecmult_gen_kb=$req_ecmult_gen_kb
-fi
-
 case $set_ecmult_gen_kb in
 2)
   SECP_CONFIG_DEFINES="$SECP_CONFIG_DEFINES -DCOMB_BLOCKS=2 -DCOMB_TEETH=5"
@@ -368,7 +361,7 @@ case $set_ecmult_gen_kb in
   SECP_CONFIG_DEFINES="$SECP_CONFIG_DEFINES -DCOMB_BLOCKS=43 -DCOMB_TEETH=6"
   ;;
 *)
-  AC_MSG_ERROR(['ecmult gen table size not 2, 22, 86 or "auto"'])
+  AC_MSG_ERROR(['ecmult gen table size not 2, 22 or 86'])
   ;;
 esac
 

From a06805ee7428d2786e631c9b5650c25fb0d46fe0 Mon Sep 17 00:00:00 2001
From: Hennadii Stepanov <32963518+hebasto@users.noreply.github.com>
Date: Mon, 27 May 2024 13:26:03 +0100
Subject: [PATCH 05/19] cmake: Remove "AUTO" value of
 `SECP256K1_ECMULT_WINDOW_SIZE` option

"AUTO" implies that a value is being chosen based on build system
introspection or host system capabilities. However, for the
`SECP256K1_ECMULT_WINDOW_SIZE` option, the value "AUTO" is hardcoded,
which might lead to confusion.

This change replaces "AUTO" with a more appropriate default value.
---
 CMakeLists.txt | 7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 88994d82..216d6465 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -92,13 +92,10 @@ if(SECP256K1_USE_EXTERNAL_DEFAULT_CALLBACKS)
   add_compile_definitions(USE_EXTERNAL_DEFAULT_CALLBACKS=1)
 endif()
 
-set(SECP256K1_ECMULT_WINDOW_SIZE "AUTO" CACHE STRING "Window size for ecmult precomputation for verification, specified as integer in range [2..24]. \"AUTO\" is a reasonable setting for desktop machines (currently 15). [default=AUTO]")
-set_property(CACHE SECP256K1_ECMULT_WINDOW_SIZE PROPERTY STRINGS "AUTO" 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24)
+set(SECP256K1_ECMULT_WINDOW_SIZE 15 CACHE STRING "Window size for ecmult precomputation for verification, specified as integer in range [2..24]. The default value is a reasonable setting for desktop machines (currently 15). [default=15]")
+set_property(CACHE SECP256K1_ECMULT_WINDOW_SIZE PROPERTY STRINGS 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24)
 include(CheckStringOptionValue)
 check_string_option_value(SECP256K1_ECMULT_WINDOW_SIZE)
-if(SECP256K1_ECMULT_WINDOW_SIZE STREQUAL "AUTO")
-  set(SECP256K1_ECMULT_WINDOW_SIZE 15)
-endif()
 add_compile_definitions(ECMULT_WINDOW_SIZE=${SECP256K1_ECMULT_WINDOW_SIZE})
 
 set(SECP256K1_ECMULT_GEN_KB "AUTO" CACHE STRING "The size of the precomputed table for signing in multiples of 1024 bytes (on typical platforms). Larger values result in possibly better signing or key generation performance at the cost of a larger table. Valid choices are 2, 22, 86. \"AUTO\" is a reasonable setting for desktop machines (currently 22). [default=AUTO]")

From 4d9645bee06e732f5d7d9e72b0c26c22c5006eb8 Mon Sep 17 00:00:00 2001
From: Hennadii Stepanov <32963518+hebasto@users.noreply.github.com>
Date: Mon, 27 May 2024 13:32:23 +0100
Subject: [PATCH 06/19] cmake: Remove "AUTO" value of `SECP256K1_ECMULT_GEN_KB`
 option

"AUTO" implies that a value is being chosen based on build system
introspection or host system capabilities. However, for the
`SECP256K1_ECMULT_GEN_KB` option, the value "AUTO" is hardcoded, which
might lead to confusion.

This change replaces "AUTO" with a more appropriate default value.
---
 CMakeLists.txt | 7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 216d6465..3d0c99b6 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -98,12 +98,9 @@ include(CheckStringOptionValue)
 check_string_option_value(SECP256K1_ECMULT_WINDOW_SIZE)
 add_compile_definitions(ECMULT_WINDOW_SIZE=${SECP256K1_ECMULT_WINDOW_SIZE})
 
-set(SECP256K1_ECMULT_GEN_KB "AUTO" CACHE STRING "The size of the precomputed table for signing in multiples of 1024 bytes (on typical platforms). Larger values result in possibly better signing or key generation performance at the cost of a larger table. Valid choices are 2, 22, 86. \"AUTO\" is a reasonable setting for desktop machines (currently 22). [default=AUTO]")
-set_property(CACHE SECP256K1_ECMULT_GEN_KB PROPERTY STRINGS "AUTO" 2 22 86)
+set(SECP256K1_ECMULT_GEN_KB 22 CACHE STRING "The size of the precomputed table for signing in multiples of 1024 bytes (on typical platforms). Larger values result in possibly better signing or key generation performance at the cost of a larger table. Valid choices are 2, 22, 86. The default value is a reasonable setting for desktop machines (currently 22). [default=22]")
+set_property(CACHE SECP256K1_ECMULT_GEN_KB PROPERTY STRINGS 2 22 86)
 check_string_option_value(SECP256K1_ECMULT_GEN_KB)
-if(SECP256K1_ECMULT_GEN_KB STREQUAL "AUTO")
-  set(SECP256K1_ECMULT_GEN_KB 22)
-endif()
 if(SECP256K1_ECMULT_GEN_KB EQUAL 2)
   add_compile_definitions(COMB_BLOCKS=2)
   add_compile_definitions(COMB_TEETH=5)

From 158f9e5eae583b1520af9ee727db342e7408dab1 Mon Sep 17 00:00:00 2001
From: Hennadii Stepanov <32963518+hebasto@users.noreply.github.com>
Date: Tue, 18 Jun 2024 15:44:15 +0100
Subject: [PATCH 07/19] cmake: Do not modify build types when integrating by
 downstream project

The `CMAKE_BUILD_TYPE` and `CMAKE_CONFIGURATION_TYPES` variables must be
managed by the downstream project.

Suggesting to review with `git diff -w`.
---
 CMakeLists.txt | 32 +++++++++++++++++---------------
 1 file changed, 17 insertions(+), 15 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index ef2b07a1..3a92a329 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -213,23 +213,25 @@ mark_as_advanced(
   CMAKE_SHARED_LINKER_FLAGS_COVERAGE
 )
 
-get_property(is_multi_config GLOBAL PROPERTY GENERATOR_IS_MULTI_CONFIG)
-set(default_build_type "RelWithDebInfo")
-if(is_multi_config)
-  set(CMAKE_CONFIGURATION_TYPES "${default_build_type}" "Release" "Debug" "MinSizeRel" "Coverage" CACHE STRING
-    "Supported configuration types."
-    FORCE
-  )
-else()
-  set_property(CACHE CMAKE_BUILD_TYPE PROPERTY
-    STRINGS "${default_build_type}" "Release" "Debug" "MinSizeRel" "Coverage"
-  )
-  if(NOT CMAKE_BUILD_TYPE)
-    message(STATUS "Setting build type to \"${default_build_type}\" as none was specified")
-    set(CMAKE_BUILD_TYPE "${default_build_type}" CACHE STRING
-      "Choose the type of build."
+if(PROJECT_IS_TOP_LEVEL)
+  get_property(is_multi_config GLOBAL PROPERTY GENERATOR_IS_MULTI_CONFIG)
+  set(default_build_type "RelWithDebInfo")
+  if(is_multi_config)
+    set(CMAKE_CONFIGURATION_TYPES "${default_build_type}" "Release" "Debug" "MinSizeRel" "Coverage" CACHE STRING
+      "Supported configuration types."
       FORCE
     )
+  else()
+    set_property(CACHE CMAKE_BUILD_TYPE PROPERTY
+      STRINGS "${default_build_type}" "Release" "Debug" "MinSizeRel" "Coverage"
+    )
+    if(NOT CMAKE_BUILD_TYPE)
+      message(STATUS "Setting build type to \"${default_build_type}\" as none was specified")
+      set(CMAKE_BUILD_TYPE "${default_build_type}" CACHE STRING
+        "Choose the type of build."
+        FORCE
+      )
+    endif()
   endif()
 endif()
 

From f87a3589f4d3bfd7a398232971bdb1ff125b8e9d Mon Sep 17 00:00:00 2001
From: Hennadii Stepanov <32963518+hebasto@users.noreply.github.com>
Date: Thu, 20 Jun 2024 21:16:30 +0100
Subject: [PATCH 08/19] cmake: Do not set `CTEST_TEST_TARGET_ALIAS`

An alias for the "test" target can be confusing for the downstream
project. So remove it.
---
 CMakeLists.txt | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index ef2b07a1..0ae8bb54 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -273,10 +273,6 @@ if(SECP256K1_BUILD_CTIME_TESTS)
   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
-set(CTEST_TEST_TARGET_ALIAS check)
 include(CTest)
 # We do not use CTest's BUILD_TESTING because a single toggle for all tests is too coarse for our needs.
 mark_as_advanced(BUILD_TESTING)

From c2764dbb99e7b8769df6814cf71beaeb59552701 Mon Sep 17 00:00:00 2001
From: Hennadii Stepanov <32963518+hebasto@users.noreply.github.com>
Date: Fri, 21 Jun 2024 14:46:42 +0100
Subject: [PATCH 09/19] cmake: Rename `SECP256K1_LATE_CFLAGS` to
 `SECP256K1_APPEND_CFLAGS`

This change follows the naming convention currently used in the Bitcoin
Core's CMake staging branch.
---
 CMakeLists.txt | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index ef2b07a1..26ca2e8f 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -284,14 +284,14 @@ if(SECP256K1_BUILD_BENCHMARK OR SECP256K1_BUILD_TESTS OR SECP256K1_BUILD_EXHAUST
   enable_testing()
 endif()
 
-set(SECP256K1_LATE_CFLAGS "" CACHE STRING "Compiler flags that are added to the command line after all other flags added by the build system.")
+set(SECP256K1_APPEND_CFLAGS "" CACHE STRING "Compiler flags that are added to the command line after all other flags added by the build system.")
 include(AllTargetsCompileOptions)
 
 add_subdirectory(src)
-all_targets_compile_options(src "${SECP256K1_LATE_CFLAGS}")
+all_targets_compile_options(src "${SECP256K1_APPEND_CFLAGS}")
 if(SECP256K1_BUILD_EXAMPLES)
   add_subdirectory(examples)
-  all_targets_compile_options(examples "${SECP256K1_LATE_CFLAGS}")
+  all_targets_compile_options(examples "${SECP256K1_APPEND_CFLAGS}")
 endif()
 
 message("\n")
@@ -365,8 +365,8 @@ else()
   message(" - LDFLAGS for executables ............ ${CMAKE_EXE_LINKER_FLAGS_DEBUG}")
   message(" - LDFLAGS for shared libraries ....... ${CMAKE_SHARED_LINKER_FLAGS_DEBUG}")
 endif()
-if(SECP256K1_LATE_CFLAGS)
-  message("SECP256K1_LATE_CFLAGS ................. ${SECP256K1_LATE_CFLAGS}")
+if(SECP256K1_APPEND_CFLAGS)
+  message("SECP256K1_APPEND_CFLAGS ............... ${SECP256K1_APPEND_CFLAGS}")
 endif()
 message("")
 if(print_msan_notice)

From 4706be2cd0bcac97da10ed3b98790f1ac6f04efb Mon Sep 17 00:00:00 2001
From: Hennadii Stepanov <32963518+hebasto@users.noreply.github.com>
Date: Fri, 21 Jun 2024 14:45:07 +0100
Subject: [PATCH 10/19] cmake: Reimplement `SECP256K1_APPEND_CFLAGS` using
 Bitcoin Core approach

---
 CMakeLists.txt                       | 10 ++++++----
 cmake/AllTargetsCompileOptions.cmake | 12 ------------
 2 files changed, 6 insertions(+), 16 deletions(-)
 delete mode 100644 cmake/AllTargetsCompileOptions.cmake

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 26ca2e8f..d91c50d7 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -284,14 +284,16 @@ if(SECP256K1_BUILD_BENCHMARK OR SECP256K1_BUILD_TESTS OR SECP256K1_BUILD_EXHAUST
   enable_testing()
 endif()
 
-set(SECP256K1_APPEND_CFLAGS "" CACHE STRING "Compiler flags that are added to the command line after all other flags added by the build system.")
-include(AllTargetsCompileOptions)
+set(SECP256K1_APPEND_CFLAGS "" CACHE STRING "Compiler flags that are appended to the command line after all other flags added by the build system. This variable is intended for debugging and special builds.")
+if(SECP256K1_APPEND_CFLAGS)
+  # Appending to this low-level rule variable is the only way to
+  # guarantee that the flags appear at the end of the command line.
+  string(APPEND CMAKE_C_COMPILE_OBJECT " ${SECP256K1_APPEND_CFLAGS}")
+endif()
 
 add_subdirectory(src)
-all_targets_compile_options(src "${SECP256K1_APPEND_CFLAGS}")
 if(SECP256K1_BUILD_EXAMPLES)
   add_subdirectory(examples)
-  all_targets_compile_options(examples "${SECP256K1_APPEND_CFLAGS}")
 endif()
 
 message("\n")
diff --git a/cmake/AllTargetsCompileOptions.cmake b/cmake/AllTargetsCompileOptions.cmake
deleted file mode 100644
index 6e420e0f..00000000
--- a/cmake/AllTargetsCompileOptions.cmake
+++ /dev/null
@@ -1,12 +0,0 @@
-# Add compile options to all targets added in the subdirectory.
-function(all_targets_compile_options dir options)
-  get_directory_property(targets DIRECTORY ${dir} BUILDSYSTEM_TARGETS)
-  separate_arguments(options)
-  set(compiled_target_types STATIC_LIBRARY SHARED_LIBRARY OBJECT_LIBRARY EXECUTABLE)
-  foreach(target ${targets})
-    get_target_property(type ${target} TYPE)
-    if(type IN_LIST compiled_target_types)
-      target_compile_options(${target} PRIVATE ${options})
-    endif()
-  endforeach()
-endfunction()

From 7454a537367609e617f0bc5e0a64738ed6fbf6e9 Mon Sep 17 00:00:00 2001
From: Sebastian Falbesoner <sebastian.falbesoner@gmail.com>
Date: Mon, 24 Jun 2024 00:55:56 +0200
Subject: [PATCH 11/19] README: mention ellswift module

Co-authored-by: Tim Ruffing <crypto@timruffing.de>
---
 README.md | 1 +
 1 file changed, 1 insertion(+)

diff --git a/README.md b/README.md
index 6e88eb4e..e8d4123a 100644
--- a/README.md
+++ b/README.md
@@ -20,6 +20,7 @@ Features:
 * Optional module for public key recovery.
 * Optional module for ECDH key exchange.
 * Optional module for Schnorr signatures according to [BIP-340](https://github.com/bitcoin/bips/blob/master/bip-0340.mediawiki).
+* Optional module for ElligatorSwift key exchange according to [BIP-324](https://github.com/bitcoin/bips/blob/master/bip-0324.mediawiki).
 
 Implementation details
 ----------------------

From 0e2fadb20c241bdd6cbbed7fcb3b4715a6133cf6 Mon Sep 17 00:00:00 2001
From: Elliot Lee <github.public@intelliot.com>
Date: Mon, 24 Jun 2024 14:24:48 -0700
Subject: [PATCH 12/19] fix: typos in secp256k1.c

---
 src/secp256k1.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/secp256k1.c b/src/secp256k1.c
index 7a327694..72d725a7 100644
--- a/src/secp256k1.c
+++ b/src/secp256k1.c
@@ -76,7 +76,7 @@ const secp256k1_context *secp256k1_context_no_precomp = &secp256k1_context_stati
 
 /* Helper function that determines if a context is proper, i.e., is not the static context or a copy thereof.
  *
- * This is intended for "context" functions such as secp256k1_context_clone. Function which need specific
+ * This is intended for "context" functions such as secp256k1_context_clone. Functions that need specific
  * features of a context should still check for these features directly. For example, a function that needs
  * ecmult_gen should directly check for the existence of the ecmult_gen context. */
 static int secp256k1_context_is_proper(const secp256k1_context* ctx) {
@@ -544,7 +544,7 @@ static int secp256k1_ecdsa_sign_inner(const secp256k1_context* ctx, secp256k1_sc
             break;
         }
         is_nonce_valid = secp256k1_scalar_set_b32_seckey(&non, nonce32);
-        /* The nonce is still secret here, but it being invalid is is less likely than 1:2^255. */
+        /* The nonce is still secret here, but it being invalid is less likely than 1:2^255. */
         secp256k1_declassify(ctx, &is_nonce_valid, sizeof(is_nonce_valid));
         if (is_nonce_valid) {
             ret = secp256k1_ecdsa_sig_sign(&ctx->ecmult_gen_ctx, r, s, &sec, &msg, &non, recid);

From fe4fbaa7f3eaa404f7ded669e611e28260839f9c Mon Sep 17 00:00:00 2001
From: Sebastian Falbesoner <sebastian.falbesoner@gmail.com>
Date: Tue, 25 Jun 2024 16:52:38 +0200
Subject: [PATCH 13/19] examples: fix case typos in secret clearing paragraphs
 (s/, Or/, or/)

---
 examples/ecdh.c    | 2 +-
 examples/ecdsa.c   | 2 +-
 examples/schnorr.c | 2 +-
 3 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/examples/ecdh.c b/examples/ecdh.c
index 4b7b7d61..d71fd2f6 100644
--- a/examples/ecdh.c
+++ b/examples/ecdh.c
@@ -108,7 +108,7 @@ int main(void) {
 
     /* It's best practice to try to clear secrets from memory after using them.
      * This is done because some bugs can allow an attacker to leak memory, for
-     * example through "out of bounds" array access (see Heartbleed), Or the OS
+     * example through "out of bounds" array access (see Heartbleed), or the OS
      * swapping them to disk. Hence, we overwrite the secret key buffer with zeros.
      *
      * Here we are preventing these writes from being optimized out, as any good compiler
diff --git a/examples/ecdsa.c b/examples/ecdsa.c
index d1d2b0e3..d5c4613d 100644
--- a/examples/ecdsa.c
+++ b/examples/ecdsa.c
@@ -128,7 +128,7 @@ int main(void) {
 
     /* It's best practice to try to clear secrets from memory after using them.
      * This is done because some bugs can allow an attacker to leak memory, for
-     * example through "out of bounds" array access (see Heartbleed), Or the OS
+     * example through "out of bounds" array access (see Heartbleed), or the OS
      * swapping them to disk. Hence, we overwrite the secret key buffer with zeros.
      *
      * Here we are preventing these writes from being optimized out, as any good compiler
diff --git a/examples/schnorr.c b/examples/schnorr.c
index 4c0dd1c1..b0409b98 100644
--- a/examples/schnorr.c
+++ b/examples/schnorr.c
@@ -146,7 +146,7 @@ int main(void) {
 
     /* It's best practice to try to clear secrets from memory after using them.
      * This is done because some bugs can allow an attacker to leak memory, for
-     * example through "out of bounds" array access (see Heartbleed), Or the OS
+     * example through "out of bounds" array access (see Heartbleed), or the OS
      * swapping them to disk. Hence, we overwrite the secret key buffer with zeros.
      *
      * Here we are preventing these writes from being optimized out, as any good compiler

From 31f84595c4fa8fcc89021790257b85416aae44f6 Mon Sep 17 00:00:00 2001
From: Sebastian Falbesoner <sebastian.falbesoner@gmail.com>
Date: Tue, 25 Jun 2024 03:11:21 +0200
Subject: [PATCH 14/19] Add ellswift usage example

This should hopefully be useful as orientation for users implementing
the key exchange part of BIP324. Conceptually the example is not very
different to the ECDH one, so a lot of code/comments are just copied
(e.g. context creation, secret key generation, shared secret comparison,
console output, cleanup with secret key clearing).
---
 .gitignore              |   1 +
 CHANGELOG.md            |   3 +
 Makefile.am             |  11 ++++
 README.md               |   1 +
 examples/CMakeLists.txt |   4 ++
 examples/ellswift.c     | 123 ++++++++++++++++++++++++++++++++++++++++
 6 files changed, 143 insertions(+)
 create mode 100644 examples/ellswift.c

diff --git a/.gitignore b/.gitignore
index 574902b8..18e3259f 100644
--- a/.gitignore
+++ b/.gitignore
@@ -10,6 +10,7 @@ ctime_tests
 ecdh_example
 ecdsa_example
 schnorr_example
+ellswift_example
 *.exe
 *.so
 *.a
diff --git a/CHANGELOG.md b/CHANGELOG.md
index a2855912..200653eb 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -7,6 +7,9 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+#### Added
+ - Added usage example for an ElligatorSwift key exchange.
+
 ## [0.5.0] - 2024-05-06
 
 #### Added
diff --git a/Makefile.am b/Makefile.am
index 322e44ea..8723b53b 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -184,6 +184,17 @@ schnorr_example_LDFLAGS += -lbcrypt
 endif
 TESTS += schnorr_example
 endif
+if ENABLE_MODULE_ELLSWIFT
+noinst_PROGRAMS += ellswift_example
+ellswift_example_SOURCES = examples/ellswift.c
+ellswift_example_CPPFLAGS = -I$(top_srcdir)/include -DSECP256K1_STATIC
+ellswift_example_LDADD = libsecp256k1.la
+ellswift_example_LDFLAGS = -static
+if BUILD_WINDOWS
+ellswift_example_LDFLAGS += -lbcrypt
+endif
+TESTS += ellswift_example
+endif
 endif
 
 ### Precomputed tables
diff --git a/README.md b/README.md
index e8d4123a..9b20dd79 100644
--- a/README.md
+++ b/README.md
@@ -114,6 +114,7 @@ Usage examples can be found in the [examples](examples) directory. To compile th
   * [ECDSA example](examples/ecdsa.c)
   * [Schnorr signatures example](examples/schnorr.c)
   * [Deriving a shared secret (ECDH) example](examples/ecdh.c)
+  * [ElligatorSwift key exchange example](examples/ellswift.c)
 
 To compile the Schnorr signature and ECDH examples, you also need to configure with `--enable-module-schnorrsig` and `--enable-module-ecdh`.
 
diff --git a/examples/CMakeLists.txt b/examples/CMakeLists.txt
index 607bb677..fd1ebce3 100644
--- a/examples/CMakeLists.txt
+++ b/examples/CMakeLists.txt
@@ -28,3 +28,7 @@ endif()
 if(SECP256K1_ENABLE_MODULE_SCHNORRSIG)
   add_example(schnorr)
 endif()
+
+if(SECP256K1_ENABLE_MODULE_ELLSWIFT)
+  add_example(ellswift)
+endif()
diff --git a/examples/ellswift.c b/examples/ellswift.c
new file mode 100644
index 00000000..52be7eeb
--- /dev/null
+++ b/examples/ellswift.c
@@ -0,0 +1,123 @@
+/*************************************************************************
+ * Written in 2024 by Sebastian Falbesoner                               *
+ * To the extent possible under law, the author(s) have dedicated all    *
+ * copyright and related and neighboring rights to the software in this  *
+ * file to the public domain worldwide. This software is distributed     *
+ * without any warranty. For the CC0 Public Domain Dedication, see       *
+ * EXAMPLES_COPYING or https://creativecommons.org/publicdomain/zero/1.0 *
+ *************************************************************************/
+
+/** This file demonstrates how to use the ElligatorSwift module to perform
+ *  a key exchange according to BIP 324. Additionally, see the documentation
+ *  in include/secp256k1_ellswift.h and doc/ellswift.md.
+ */
+
+#include <stdio.h>
+#include <assert.h>
+#include <string.h>
+
+#include <secp256k1.h>
+#include <secp256k1_ellswift.h>
+
+#include "examples_util.h"
+
+int main(void) {
+    secp256k1_context* ctx;
+    unsigned char randomize[32];
+    unsigned char auxrand1[32];
+    unsigned char auxrand2[32];
+    unsigned char seckey1[32];
+    unsigned char seckey2[32];
+    unsigned char ellswift_pubkey1[64];
+    unsigned char ellswift_pubkey2[64];
+    unsigned char shared_secret1[32];
+    unsigned char shared_secret2[32];
+    int return_val;
+
+    /* Create a secp256k1 context */
+    ctx = secp256k1_context_create(SECP256K1_CONTEXT_NONE);
+    if (!fill_random(randomize, sizeof(randomize))) {
+        printf("Failed to generate randomness\n");
+        return 1;
+    }
+    /* Randomizing the context is recommended to protect against side-channel
+     * leakage. See `secp256k1_context_randomize` in secp256k1.h for more
+     * information about it. This should never fail. */
+    return_val = secp256k1_context_randomize(ctx, randomize);
+    assert(return_val);
+
+    /*** Generate secret keys ***/
+
+    /* If the secret key is zero or out of range (bigger than secp256k1's
+     * order), we try to sample a new key. Note that the probability of this
+     * happening is negligible. */
+    while (1) {
+        if (!fill_random(seckey1, sizeof(seckey1)) || !fill_random(seckey2, sizeof(seckey2))) {
+            printf("Failed to generate randomness\n");
+            return 1;
+        }
+        if (secp256k1_ec_seckey_verify(ctx, seckey1) && secp256k1_ec_seckey_verify(ctx, seckey2)) {
+            break;
+        }
+    }
+
+    /* Generate ElligatorSwift public keys. This should never fail with valid context and
+       verified secret keys. Note that providing additional randomness (fourth parameter) is
+       optional, but recommended. */
+    if (!fill_random(auxrand1, sizeof(auxrand1)) || !fill_random(auxrand2, sizeof(auxrand2))) {
+        printf("Failed to generate randomness\n");
+        return 1;
+    }
+    return_val = secp256k1_ellswift_create(ctx, ellswift_pubkey1, seckey1, auxrand1);
+    assert(return_val);
+    return_val = secp256k1_ellswift_create(ctx, ellswift_pubkey2, seckey2, auxrand2);
+    assert(return_val);
+
+    /*** Create the shared secret on each side ***/
+
+    /* Perform x-only ECDH with seckey1 and ellswift_pubkey2. Should never fail
+     * with a verified seckey and valid pubkey. Note that both parties pass both
+     * EllSwift pubkeys in the same order; the pubkey of the calling party is
+     * determined by the "party" boolean (sixth parameter). */
+    return_val = secp256k1_ellswift_xdh(ctx, shared_secret1, ellswift_pubkey1, ellswift_pubkey2,
+        seckey1, 0, secp256k1_ellswift_xdh_hash_function_bip324, NULL);
+    assert(return_val);
+
+    /* Perform x-only ECDH with seckey2 and ellswift_pubkey1. Should never fail
+     * with a verified seckey and valid pubkey. */
+    return_val = secp256k1_ellswift_xdh(ctx, shared_secret2, ellswift_pubkey1, ellswift_pubkey2,
+        seckey2, 1, secp256k1_ellswift_xdh_hash_function_bip324, NULL);
+    assert(return_val);
+
+    /* Both parties should end up with the same shared secret */
+    return_val = memcmp(shared_secret1, shared_secret2, sizeof(shared_secret1));
+    assert(return_val == 0);
+
+    printf(  "     Secret Key1: ");
+    print_hex(seckey1, sizeof(seckey1));
+    printf(  "EllSwift Pubkey1: ");
+    print_hex(ellswift_pubkey1, sizeof(ellswift_pubkey1));
+    printf("\n     Secret Key2: ");
+    print_hex(seckey2, sizeof(seckey2));
+    printf(  "EllSwift Pubkey2: ");
+    print_hex(ellswift_pubkey2, sizeof(ellswift_pubkey2));
+    printf("\n   Shared Secret: ");
+    print_hex(shared_secret1, sizeof(shared_secret1));
+
+    /* This will clear everything from the context and free the memory */
+    secp256k1_context_destroy(ctx);
+
+    /* It's best practice to try to clear secrets from memory after using them.
+     * This is done because some bugs can allow an attacker to leak memory, for
+     * example through "out of bounds" array access (see Heartbleed), or the OS
+     * swapping them to disk. Hence, we overwrite the secret key buffer with zeros.
+     *
+     * Here we are preventing these writes from being optimized out, as any good compiler
+     * will remove any writes that aren't used. */
+    secure_erase(seckey1, sizeof(seckey1));
+    secure_erase(seckey2, sizeof(seckey2));
+    secure_erase(shared_secret1, sizeof(shared_secret1));
+    secure_erase(shared_secret2, sizeof(shared_secret2));
+
+    return 0;
+}

From b8fe33332b7c6a7700f74be20c022fcc49753cd2 Mon Sep 17 00:00:00 2001
From: Eduardo Menges Mattje <eduardomattje@gmail.com>
Date: Thu, 27 Jun 2024 11:46:48 -0300
Subject: [PATCH 15/19] cmake: Fixed O3 replacement

---
 CMakeLists.txt | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 7e3465a7..46abe062 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -185,7 +185,7 @@ else()
   string(REGEX REPLACE "-DNDEBUG[ \t\r\n]*" "" CMAKE_C_FLAGS_RELEASE "${CMAKE_C_FLAGS_RELEASE}")
   string(REGEX REPLACE "-DNDEBUG[ \t\r\n]*" "" CMAKE_C_FLAGS_MINSIZEREL "${CMAKE_C_FLAGS_MINSIZEREL}")
   # Prefer -O2 optimization level. (-O3 is CMake's default for Release for many compilers.)
-  string(REGEX REPLACE "-O3[ \t\r\n]*" "-O2" CMAKE_C_FLAGS_RELEASE "${CMAKE_C_FLAGS_RELEASE}")
+  string(REGEX REPLACE "-O3( |$)" "-O2\\1" CMAKE_C_FLAGS_RELEASE "${CMAKE_C_FLAGS_RELEASE}")
 endif()
 
 # Define custom "Coverage" build type.

From 16685649d2a6e52f81659ec629bc4e603128c54c Mon Sep 17 00:00:00 2001
From: Tim Ruffing <crypto@timruffing.de>
Date: Mon, 1 Jul 2024 18:40:24 +0200
Subject: [PATCH 16/19] doc: Add convention for defaults

---
 CONTRIBUTING.md | 1 +
 1 file changed, 1 insertion(+)

diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index 5fbf7332..a366d38b 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -49,6 +49,7 @@ In addition, libsecp256k1 tries to maintain the following coding conventions:
 * Operations involving secret data should be tested for being constant time with respect to the secrets (see [src/ctime_tests.c](src/ctime_tests.c)).
 * Local variables containing secret data should be cleared explicitly to try to delete secrets from memory.
 * Use `secp256k1_memcmp_var` instead of `memcmp` (see [#823](https://github.com/bitcoin-core/secp256k1/issues/823)).
+* As a rule of thumb, the default values for configuration options should target standard desktop machines and align with Bitcoin Core's defaults, and the tests should mostly exercise the default configuration (see [#1549](https://github.com/bitcoin-core/secp256k1/issues/1549#issuecomment-2200559257)).
 
 #### Style conventions
 

From 9420eece24117fc55540ab6d8bbfaca6b834b761 Mon Sep 17 00:00:00 2001
From: Hennadii Stepanov <32963518+hebasto@users.noreply.github.com>
Date: Mon, 1 Jul 2024 22:46:05 +0100
Subject: [PATCH 17/19] cmake: Bump CMake minimum required version up to 3.16

---
 .github/workflows/ci.yml | 2 +-
 CMakeLists.txt           | 9 +--------
 README.md                | 2 +-
 doc/release-process.md   | 2 +-
 4 files changed, 4 insertions(+), 11 deletions(-)

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index ade94e1e..ded5df36 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -864,5 +864,5 @@ jobs:
           CI_BUILD: ${{ runner.temp }}/${{ github.run_id }}${{ github.action }}/build
           CI_INSTALL: ${{ runner.temp }}/${{ github.run_id }}${{ github.action }}/install
         run: |
-          cmake -B ${{ env.CI_BUILD }} -DCMAKE_INSTALL_PREFIX=${{ env.CI_INSTALL }} && cmake --build ${{ env.CI_BUILD }} --target install && ls -RlAh ${{ env.CI_INSTALL }}
+          cmake -B ${{ env.CI_BUILD }} -DCMAKE_INSTALL_PREFIX=${{ env.CI_INSTALL }} && cmake --build ${{ env.CI_BUILD }} && cmake --install ${{ env.CI_BUILD }} && ls -RlAh ${{ env.CI_INSTALL }}
           gcc -o ecdsa examples/ecdsa.c -I ${{ env.CI_INSTALL }}/include -L ${{ env.CI_INSTALL }}/lib*/ -l secp256k1 -Wl,-rpath,"${{ env.CI_INSTALL }}/lib",-rpath,"${{ env.CI_INSTALL }}/lib64" && ./ecdsa
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 46abe062..8d1e8e40 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1,11 +1,4 @@
-cmake_minimum_required(VERSION 3.13)
-
-if(CMAKE_VERSION VERSION_GREATER_EQUAL 3.15)
-  # MSVC runtime library flags are selected by the CMAKE_MSVC_RUNTIME_LIBRARY abstraction.
-  cmake_policy(SET CMP0091 NEW)
-  # MSVC warning flags are not in CMAKE_<LANG>_FLAGS by default.
-  cmake_policy(SET CMP0092 NEW)
-endif()
+cmake_minimum_required(VERSION 3.16)
 
 project(libsecp256k1
   # The package (a.k.a. release) version is based on semantic versioning 2.0.0 of
diff --git a/README.md b/README.md
index e8d4123a..6a2ea438 100644
--- a/README.md
+++ b/README.md
@@ -82,7 +82,7 @@ To maintain a pristine source tree, CMake encourages to perform an out-of-source
     $ cmake ..
     $ cmake --build .
     $ ctest  # run the test suite
-    $ sudo cmake --build . --target install  # optional
+    $ sudo cmake --install .  # optional
 
 To compile optional modules (such as Schnorr signatures), you need to run `cmake` with additional flags (such as `-DSECP256K1_ENABLE_MODULE_SCHNORRSIG=ON`). Run `cmake .. -LH` to see the full list of available flags.
 
diff --git a/doc/release-process.md b/doc/release-process.md
index cdf62430..c37f519d 100644
--- a/doc/release-process.md
+++ b/doc/release-process.md
@@ -31,7 +31,7 @@ Perform these checks when reviewing the release PR (see below):
    ```shell
    dir=$(mktemp -d)
    build=$(mktemp -d)
-   cmake -B $build -DCMAKE_INSTALL_PREFIX=$dir && cmake --build $build --target install && ls -RlAh $dir
+   cmake -B $build -DCMAKE_INSTALL_PREFIX=$dir && cmake --build $build && cmake --install $build && ls -RlAh $dir
    gcc -o ecdsa examples/ecdsa.c -I $dir/include -L $dir/lib*/ -l secp256k1 -Wl,-rpath,"$dir/lib",-rpath,"$dir/lib64" && ./ecdsa
    ```
 4. Use the [`check-abi.sh`](/tools/check-abi.sh) tool to verify that there are no unexpected ABI incompatibilities and that the version number and the release notes accurately reflect all potential ABI changes. To run this tool, the `abi-dumper` and `abi-compliance-checker` packages are required.

From d94a9273f82aeb468f9c48f6da5ee9abc64c024a Mon Sep 17 00:00:00 2001
From: Hennadii Stepanov <32963518+hebasto@users.noreply.github.com>
Date: Mon, 1 Jul 2024 20:41:36 +0100
Subject: [PATCH 18/19] build: Adjust the default size of the precomputed table
 for signing

The new default value of the precomputed table for signing is aligned
with Bitcoin Core's default.
See: https://github.com/bitcoin/bitcoin/commit/a057869aa3c42457570765966cb66accb2375b13
---
 CMakeLists.txt | 2 +-
 configure.ac   | 4 ++--
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 8d1e8e40..7a876860 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -90,7 +90,7 @@ include(CheckStringOptionValue)
 check_string_option_value(SECP256K1_ECMULT_WINDOW_SIZE)
 add_compile_definitions(ECMULT_WINDOW_SIZE=${SECP256K1_ECMULT_WINDOW_SIZE})
 
-set(SECP256K1_ECMULT_GEN_KB 22 CACHE STRING "The size of the precomputed table for signing in multiples of 1024 bytes (on typical platforms). Larger values result in possibly better signing or key generation performance at the cost of a larger table. Valid choices are 2, 22, 86. The default value is a reasonable setting for desktop machines (currently 22). [default=22]")
+set(SECP256K1_ECMULT_GEN_KB 86 CACHE STRING "The size of the precomputed table for signing in multiples of 1024 bytes (on typical platforms). Larger values result in possibly better signing or key generation performance at the cost of a larger table. Valid choices are 2, 22, 86. The default value is a reasonable setting for desktop machines (currently 86). [default=86]")
 set_property(CACHE SECP256K1_ECMULT_GEN_KB PROPERTY STRINGS 2 22 86)
 check_string_option_value(SECP256K1_ECMULT_GEN_KB)
 if(SECP256K1_ECMULT_GEN_KB EQUAL 2)
diff --git a/configure.ac b/configure.ac
index adae1897..24918885 100644
--- a/configure.ac
+++ b/configure.ac
@@ -216,9 +216,9 @@ AC_ARG_WITH([ecmult-window], [AS_HELP_STRING([--with-ecmult-window=SIZE],
 AC_ARG_WITH([ecmult-gen-kb], [AS_HELP_STRING([--with-ecmult-gen-kb=2|22|86],
 [The size of the precomputed table for signing in multiples of 1024 bytes (on typical platforms).]
 [Larger values result in possibly better signing/keygeneration performance at the cost of a larger table.]
-[The default value is a reasonable setting for desktop machines (currently 22). [default=22]]
+[The default value is a reasonable setting for desktop machines (currently 86). [default=86]]
 )],
-[set_ecmult_gen_kb=$withval], [set_ecmult_gen_kb=22])
+[set_ecmult_gen_kb=$withval], [set_ecmult_gen_kb=86])
 
 AC_ARG_WITH([valgrind], [AS_HELP_STRING([--with-valgrind=yes|no|auto],
 [Build with extra checks for running inside Valgrind [default=auto]]

From e2af491263e2f7e086dc7f1925d86660ff265dc6 Mon Sep 17 00:00:00 2001
From: Hennadii Stepanov <32963518+hebasto@users.noreply.github.com>
Date: Mon, 1 Jul 2024 20:44:23 +0100
Subject: [PATCH 19/19] ci: Switch to the new default value of the precomputed
 table for signing

---
 .github/workflows/ci.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index ded5df36..56a8c9f6 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -22,7 +22,7 @@ env:
   BUILD: 'check'
   ### secp256k1 config
   ECMULTWINDOW: 15
-  ECMULTGENKB: 22
+  ECMULTGENKB: 86
   ASM: 'no'
   WIDEMUL: 'auto'
   WITH_VALGRIND: 'yes'