From f0aec78d9377e84db7cca0b5cb5d67204ee4e216 Mon Sep 17 00:00:00 2001
From: Hennadii Stepanov <32963518+hebasto@users.noreply.github.com>
Date: Fri, 28 Jun 2024 12:22:51 +0100
Subject: [PATCH 1/8] cmake: Switch to libsecp256k1 upstream build system

---
 CMakeLists.txt        |  1 -
 cmake/secp256k1.cmake | 62 -------------------------------------------
 src/CMakeLists.txt    | 20 ++++++++++++--
 3 files changed, 18 insertions(+), 65 deletions(-)
 delete mode 100644 cmake/secp256k1.cmake

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 4583af6d5efaa..5067151257786 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -369,7 +369,6 @@ include(cmake/ccache.cmake)
 include(cmake/crc32c.cmake)
 include(cmake/leveldb.cmake)
 include(cmake/minisketch.cmake)
-include(cmake/secp256k1.cmake)
 
 add_library(warn_interface INTERFACE)
 target_link_libraries(core_interface INTERFACE warn_interface)
diff --git a/cmake/secp256k1.cmake b/cmake/secp256k1.cmake
deleted file mode 100644
index 22139e519b4a8..0000000000000
--- a/cmake/secp256k1.cmake
+++ /dev/null
@@ -1,62 +0,0 @@
-# Copyright (c) 2023-present The Bitcoin Core developers
-# Distributed under the MIT software license, see the accompanying
-# file COPYING or https://opensource.org/license/mit/.
-
-# This file is part of the transition from Autotools to CMake. Once CMake
-# support has been merged we should switch to using the upstream CMake
-# buildsystem.
-
-enable_language(C)
-set(CMAKE_C_STANDARD 90)
-set(CMAKE_C_EXTENSIONS OFF)
-string(APPEND CMAKE_C_COMPILE_OBJECT " ${APPEND_CPPFLAGS} ${APPEND_CFLAGS}")
-
-include(CheckCSourceCompiles)
-check_c_source_compiles("
-  #include <stdint.h>
-
-  int main()
-  {
-    uint64_t a = 11, tmp;
-    __asm__ __volatile__(\"movq $0x100000000,%1; mulq %%rsi\" : \"+a\"(a) : \"S\"(tmp) : \"cc\", \"%rdx\");
-  }
-  " HAVE_64BIT_ASM
-)
-
-add_library(secp256k1 STATIC EXCLUDE_FROM_ALL
-  ${PROJECT_SOURCE_DIR}/src/secp256k1/src/secp256k1.c
-  ${PROJECT_SOURCE_DIR}/src/secp256k1/src/precomputed_ecmult.c
-  ${PROJECT_SOURCE_DIR}/src/secp256k1/src/precomputed_ecmult_gen.c
-)
-
-target_compile_definitions(secp256k1
-  PRIVATE
-    ECMULT_WINDOW_SIZE=15
-    ENABLE_MODULE_RECOVERY
-    ENABLE_MODULE_SCHNORRSIG
-    ENABLE_MODULE_EXTRAKEYS
-    ENABLE_MODULE_ELLSWIFT
-    # COMB_* definitions for SECP256K1_ECMULT_GEN_KB=86
-    COMB_BLOCKS=43
-    COMB_TEETH=6
-    $<$<BOOL:${HAVE_64BIT_ASM}>:USE_ASM_X86_64=1>
-  INTERFACE
-    $<$<PLATFORM_ID:Windows>:SECP256K1_STATIC>
-)
-
-target_include_directories(secp256k1
-  PUBLIC
-    $<BUILD_INTERFACE:${PROJECT_SOURCE_DIR}/src/secp256k1/include>
-)
-
-if(MSVC)
-  target_compile_options(secp256k1
-    PRIVATE
-      /wd4146
-      /wd4244
-      /wd4267
-  )
-endif()
-
-target_link_libraries(secp256k1 PRIVATE core_base_interface)
-set_target_properties(secp256k1 PROPERTIES EXPORT_COMPILE_COMMANDS OFF)
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 6116b817bc403..39477ebeb3751 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -1,6 +1,6 @@
-# Copyright (c) 2023 The Bitcoin Core developers
+# Copyright (c) 2023-present The Bitcoin Core developers
 # Distributed under the MIT software license, see the accompanying
-# file COPYING or http://www.opensource.org/licenses/mit-license.php.
+# file COPYING or https://opensource.org/license/mit/.
 
 include(GNUInstallDirs)
 include(AddWindowsResources)
@@ -38,6 +38,22 @@ if(WITH_MULTIPROCESS)
   add_subdirectory(ipc)
 endif()
 
+#=============================
+# secp256k1 subtree
+#=============================
+message("")
+message("Configuring secp256k1 subtree...")
+set(SECP256K1_DISABLE_SHARED ON CACHE BOOL "" FORCE)
+set(SECP256K1_ENABLE_MODULE_ECDH OFF CACHE BOOL "" FORCE)
+set(SECP256K1_ENABLE_MODULE_RECOVERY ON CACHE BOOL "" FORCE)
+set(SECP256K1_ECMULT_GEN_KB 86 CACHE STRING "" FORCE)
+include(GetTargetInterface)
+get_target_interface(core_c_flags "" core_base_interface COMPILE_OPTIONS)
+set(SECP256K1_LATE_CFLAGS ${core_c_flags} CACHE STRING "" FORCE)
+unset(core_c_flags)
+add_subdirectory(secp256k1 EXCLUDE_FROM_ALL)
+set_target_properties(secp256k1 PROPERTIES EXPORT_COMPILE_COMMANDS OFF)
+string(APPEND CMAKE_C_COMPILE_OBJECT " ${APPEND_CPPFLAGS} ${APPEND_CFLAGS}")
 
 # Stable, backwards-compatible consensus functionality.
 add_library(bitcoin_consensus STATIC EXCLUDE_FROM_ALL

From c3134b05d2fed18739a0bb2d854d3216db3add6a Mon Sep 17 00:00:00 2001
From: Hennadii Stepanov <32963518+hebasto@users.noreply.github.com>
Date: Sat, 25 May 2024 10:15:03 +0100
Subject: [PATCH 2/8] cmake: Let libsecp256k1 manage config-specific C flags

---
 CMakeLists.txt                           | 24 ++------------------
 cmake/module/ProcessConfigurations.cmake | 28 ------------------------
 2 files changed, 2 insertions(+), 50 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 5067151257786..23de7b4d64b98 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -428,15 +428,12 @@ target_compile_definitions(core_interface_debug INTERFACE
 )
 # We leave assertions on.
 if(MSVC)
-  remove_c_flag_from_all_configs(/DNDEBUG)
   remove_cxx_flag_from_all_configs(/DNDEBUG)
 else()
-  remove_c_flag_from_all_configs(-DNDEBUG)
   remove_cxx_flag_from_all_configs(-DNDEBUG)
 
-  # Adjust flags used by the C/CXX compiler during RELEASE builds.
+  # Adjust flags used by the CXX compiler during RELEASE builds.
   # Prefer -O2 optimization level. (-O3 is CMake's default for Release for many compilers.)
-  replace_c_flag_in_config(Release -O3 -O2)
   replace_cxx_flag_in_config(Release -O3 -O2)
 
   are_flags_overridden(CMAKE_CXX_FLAGS_DEBUG cxx_flags_debug_overridden)
@@ -446,6 +443,7 @@ else()
     if(compiler_supports_g3)
       replace_cxx_flag_in_config(Debug -g -g3)
     endif()
+    unset(compiler_supports_g3)
 
     try_append_cxx_flags("-ftrapv" RESULT_VAR compiler_supports_ftrapv)
     if(compiler_supports_ftrapv)
@@ -462,24 +460,6 @@ else()
     )
   endif()
   unset(cxx_flags_debug_overridden)
-
-  are_flags_overridden(CMAKE_C_FLAGS_DEBUG c_flags_debug_overridden)
-  if(NOT c_flags_debug_overridden)
-    # Redefine flags used by the C compiler during DEBUG builds.
-    if(compiler_supports_g3)
-      replace_c_flag_in_config(Debug -g -g3)
-    endif()
-
-    string(PREPEND CMAKE_C_FLAGS_DEBUG "-O0 ")
-
-    set(CMAKE_C_FLAGS_DEBUG "${CMAKE_C_FLAGS_DEBUG}"
-      CACHE STRING
-      "Flags used by the C compiler during DEBUG builds."
-      FORCE
-    )
-  endif()
-  unset(compiler_supports_g3)
-  unset(c_flags_debug_overridden)
 endif()
 
 set(CMAKE_CXX_FLAGS_COVERAGE "-Og --coverage")
diff --git a/cmake/module/ProcessConfigurations.cmake b/cmake/module/ProcessConfigurations.cmake
index d5895497deb26..e53df8c14f112 100644
--- a/cmake/module/ProcessConfigurations.cmake
+++ b/cmake/module/ProcessConfigurations.cmake
@@ -84,23 +84,6 @@ function(set_default_config config)
   endif()
 endfunction()
 
-function(remove_c_flag_from_all_configs flag)
-  get_all_configs(all_configs)
-  foreach(config IN LISTS all_configs)
-    string(TOUPPER "${config}" config_uppercase)
-    set(flags "${CMAKE_C_FLAGS_${config_uppercase}}")
-    separate_arguments(flags)
-    list(FILTER flags EXCLUDE REGEX "${flag}")
-    list(JOIN flags " " new_flags)
-    set(CMAKE_C_FLAGS_${config_uppercase} "${new_flags}" PARENT_SCOPE)
-    set(CMAKE_C_FLAGS_${config_uppercase} "${new_flags}"
-      CACHE STRING
-      "Flags used by the C compiler during ${config_uppercase} builds."
-      FORCE
-    )
-  endforeach()
-endfunction()
-
 function(remove_cxx_flag_from_all_configs flag)
   get_all_configs(all_configs)
   foreach(config IN LISTS all_configs)
@@ -118,17 +101,6 @@ function(remove_cxx_flag_from_all_configs flag)
   endforeach()
 endfunction()
 
-function(replace_c_flag_in_config config old_flag new_flag)
-  string(TOUPPER "${config}" config_uppercase)
-  string(REGEX REPLACE "(^| )${old_flag}( |$)" "\\1${new_flag}\\2" new_flags "${CMAKE_C_FLAGS_${config_uppercase}}")
-  set(CMAKE_C_FLAGS_${config_uppercase} "${new_flags}" PARENT_SCOPE)
-  set(CMAKE_C_FLAGS_${config_uppercase} "${new_flags}"
-    CACHE STRING
-    "Flags used by the C compiler during ${config_uppercase} builds."
-    FORCE
-  )
-endfunction()
-
 function(replace_cxx_flag_in_config config old_flag new_flag)
   string(TOUPPER "${config}" config_uppercase)
   string(REGEX REPLACE "(^| )${old_flag}( |$)" "\\1${new_flag}\\2" new_flags "${CMAKE_CXX_FLAGS_${config_uppercase}}")

From 469e1ade67406aaf63f2845acb7dff5b2e223a93 Mon Sep 17 00:00:00 2001
From: Hennadii Stepanov <32963518+hebasto@users.noreply.github.com>
Date: Sat, 25 May 2024 10:15:03 +0100
Subject: [PATCH 3/8] cmake: Remove C stuff from summary

---
 CMakeLists.txt                  |  1 -
 cmake/module/FlagsSummary.cmake | 11 -----------
 2 files changed, 12 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 23de7b4d64b98..88993778398ca 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -643,7 +643,6 @@ else()
   set(cross_status "FALSE")
 endif()
 message("Cross compiling ....................... ${cross_status}")
-message("C compiler ............................ ${CMAKE_C_COMPILER_ID} ${CMAKE_C_COMPILER_VERSION}, ${CMAKE_C_COMPILER}")
 message("C++ compiler .......................... ${CMAKE_CXX_COMPILER_ID} ${CMAKE_CXX_COMPILER_VERSION}, ${CMAKE_CXX_COMPILER}")
 include(FlagsSummary)
 flags_summary()
diff --git a/cmake/module/FlagsSummary.cmake b/cmake/module/FlagsSummary.cmake
index b3e9a5ed65910..563146716cb8e 100644
--- a/cmake/module/FlagsSummary.cmake
+++ b/cmake/module/FlagsSummary.cmake
@@ -22,17 +22,6 @@ function(print_flags_per_config config indent_num)
   get_target_interface(definitions ${config} core_interface COMPILE_DEFINITIONS)
   indent_message("Preprocessor defined macros ..........." "${definitions}" ${indent_num})
 
-  string(STRIP "${CMAKE_C_FLAGS} ${CMAKE_C_FLAGS_${config_uppercase}}" combined_c_flags)
-  string(STRIP "${combined_c_flags} ${CMAKE_C${CMAKE_C_STANDARD}_STANDARD_COMPILE_OPTION}" combined_c_flags)
-  if(CMAKE_POSITION_INDEPENDENT_CODE)
-    string(JOIN " " combined_c_flags ${combined_c_flags} ${CMAKE_C_COMPILE_OPTIONS_PIC})
-  endif()
-  get_target_interface(core_c_flags ${config} core_base_interface COMPILE_OPTIONS)
-  string(STRIP "${combined_c_flags} ${core_c_flags}" combined_c_flags)
-  string(STRIP "${combined_c_flags} ${APPEND_CPPFLAGS}" combined_c_flags)
-  string(STRIP "${combined_c_flags} ${APPEND_CFLAGS}" combined_c_flags)
-  indent_message("C compiler flags ......................" "${combined_c_flags}" ${indent_num})
-
   string(STRIP "${CMAKE_CXX_FLAGS} ${CMAKE_CXX_FLAGS_${config_uppercase}}" combined_cxx_flags)
   string(STRIP "${combined_cxx_flags} ${CMAKE_CXX${CMAKE_CXX_STANDARD}_STANDARD_COMPILE_OPTION}" combined_cxx_flags)
   if(CMAKE_POSITION_INDEPENDENT_CODE)

From 65f15d127ca33d69cd3ca3acc20a25d179703822 Mon Sep 17 00:00:00 2001
From: Hennadii Stepanov <32963518+hebasto@users.noreply.github.com>
Date: Tue, 25 Jun 2024 13:48:14 +0100
Subject: [PATCH 4/8] cmake: Pass to secp256k1 build system only sanitizer
 flags

This change mirrors behavior in the master branch.
---
 CMakeLists.txt     | 6 ++++--
 src/CMakeLists.txt | 8 +++++---
 2 files changed, 9 insertions(+), 5 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 88993778398ca..3872c812067a8 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -322,11 +322,13 @@ target_link_libraries(core_base_interface INTERFACE
   Threads::Threads
 )
 
+add_library(sanitize_interface INTERFACE)
+target_link_libraries(core_base_interface INTERFACE sanitize_interface)
 if(SANITIZERS)
   # First check if the compiler accepts flags. If an incompatible pair like
   # -fsanitize=address,thread is used here, this check will fail. This will also
   # fail if a bad argument is passed, e.g. -fsanitize=undfeined
-  try_append_cxx_flags("-fsanitize=${SANITIZERS}" TARGET core_base_interface
+  try_append_cxx_flags("-fsanitize=${SANITIZERS}" TARGET sanitize_interface
     RESULT_VAR cxx_supports_sanitizers
     SKIP_LINK
   )
@@ -353,7 +355,7 @@ if(SANITIZERS)
     message(FATAL_ERROR "Linker did not accept requested flags, you are missing required libraries.")
   endif()
 endif()
-target_link_options(core_base_interface INTERFACE ${SANITIZER_LDFLAGS})
+target_link_options(sanitize_interface INTERFACE ${SANITIZER_LDFLAGS})
 
 include(AddBoostIfNeeded)
 add_boost_if_needed()
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 39477ebeb3751..902b0248cddbe 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -48,9 +48,11 @@ set(SECP256K1_ENABLE_MODULE_ECDH OFF CACHE BOOL "" FORCE)
 set(SECP256K1_ENABLE_MODULE_RECOVERY ON CACHE BOOL "" FORCE)
 set(SECP256K1_ECMULT_GEN_KB 86 CACHE STRING "" FORCE)
 include(GetTargetInterface)
-get_target_interface(core_c_flags "" core_base_interface COMPILE_OPTIONS)
-set(SECP256K1_LATE_CFLAGS ${core_c_flags} CACHE STRING "" FORCE)
-unset(core_c_flags)
+# -fsanitize and related flags apply to both C++ and C,
+# so we can pass them down to libsecp256k1 as CFLAGS.
+get_target_interface(core_sanitizer_cxx_flags "" sanitize_interface COMPILE_OPTIONS)
+set(SECP256K1_LATE_CFLAGS ${core_sanitizer_cxx_flags} CACHE STRING "" FORCE)
+unset(core_sanitizer_cxx_flags)
 add_subdirectory(secp256k1 EXCLUDE_FROM_ALL)
 set_target_properties(secp256k1 PROPERTIES EXPORT_COMPILE_COMMANDS OFF)
 string(APPEND CMAKE_C_COMPILE_OBJECT " ${APPEND_CPPFLAGS} ${APPEND_CFLAGS}")

From cdd843a9e703076287bad54bebb800c4507ff753 Mon Sep 17 00:00:00 2001
From: Hennadii Stepanov <32963518+hebasto@users.noreply.github.com>
Date: Sat, 22 Jun 2024 16:00:06 +0100
Subject: [PATCH 5/8] cmake: Override build configurations for libsecp256k1

---
 src/CMakeLists.txt | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 902b0248cddbe..9558674fe3f56 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -53,6 +53,15 @@ include(GetTargetInterface)
 get_target_interface(core_sanitizer_cxx_flags "" sanitize_interface COMPILE_OPTIONS)
 set(SECP256K1_LATE_CFLAGS ${core_sanitizer_cxx_flags} CACHE STRING "" FORCE)
 unset(core_sanitizer_cxx_flags)
+# We want to build libsecp256k1 with the most tested RelWithDebInfo configuration.
+enable_language(C)
+foreach(config IN LISTS CMAKE_BUILD_TYPE CMAKE_CONFIGURATION_TYPES)
+  if(config STREQUAL "")
+    continue()
+  endif()
+  string(TOUPPER "${config}" config)
+  set(CMAKE_C_FLAGS_${config} "${CMAKE_C_FLAGS_RELWITHDEBINFO}")
+endforeach()
 add_subdirectory(secp256k1 EXCLUDE_FROM_ALL)
 set_target_properties(secp256k1 PROPERTIES EXPORT_COMPILE_COMMANDS OFF)
 string(APPEND CMAKE_C_COMPILE_OBJECT " ${APPEND_CPPFLAGS} ${APPEND_CFLAGS}")

From 70ec2d938616f3a740670ddea216e105bcd28be7 Mon Sep 17 00:00:00 2001
From: Hennadii Stepanov <32963518+hebasto@users.noreply.github.com>
Date: Tue, 25 Jun 2024 10:47:09 +0100
Subject: [PATCH 6/8] cmake: Reorder subdirectories
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

This change ensures that both summaries—secp256k1's and Bitcoin Core's—
are displayed without interleaving of the `find_package(Doxygen)` output
from the `doc` subdirectory.
---
 CMakeLists.txt | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 3872c812067a8..af07c719a75a5 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -588,10 +588,11 @@ endif()
 # - https://github.com/bitcoin/bitcoin/pull/30312#issuecomment-2191235833
 set(CMAKE_SKIP_BUILD_RPATH TRUE)
 set(CMAKE_SKIP_INSTALL_RPATH TRUE)
-add_subdirectory(src)
 add_subdirectory(test)
 add_subdirectory(doc)
 
+add_subdirectory(src)
+
 include(cmake/tests.cmake)
 
 include(Maintenance)

From bfe7c4d556f5e5a5b8cf4497444c270eaeaf99f3 Mon Sep 17 00:00:00 2001
From: Hennadii Stepanov <32963518+hebasto@users.noreply.github.com>
Date: Wed, 26 Jun 2024 21:32:37 +0100
Subject: [PATCH 7/8] [FIXUP] cmake: Enable tests before adding subdirectories

---
 CMakeLists.txt    | 3 +++
 cmake/tests.cmake | 2 --
 2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index af07c719a75a5..1dd2a42085e9e 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -580,6 +580,9 @@ if(DEFINED ENV{LDFLAGS})
   deduplicate_flags(CMAKE_EXE_LINKER_FLAGS)
 endif()
 
+if(BUILD_TESTS)
+  enable_testing()
+endif()
 # TODO: The `CMAKE_SKIP_BUILD_RPATH` variable setting can be deleted
 #       in the future after reordering Guix script commands to
 #       perform binary checks after the installation step.
diff --git a/cmake/tests.cmake b/cmake/tests.cmake
index 0abccf5999f1e..7f597262c82d0 100644
--- a/cmake/tests.cmake
+++ b/cmake/tests.cmake
@@ -2,8 +2,6 @@
 # Distributed under the MIT software license, see the accompanying
 # file COPYING or https://opensource.org/license/mit/.
 
-include(CTest)
-
 if(TARGET bitcoin-util AND TARGET bitcoin-tx AND PYTHON_COMMAND)
   add_test(NAME util_test_runner
     COMMAND ${CMAKE_COMMAND} -E env BITCOINUTIL=$<TARGET_FILE:bitcoin-util> BITCOINTX=$<TARGET_FILE:bitcoin-tx> ${PYTHON_COMMAND} ${CMAKE_BINARY_DIR}/test/util/test_runner.py

From 458d54c57de3f4708a5e1b3e7b6ef1aac9ea4247 Mon Sep 17 00:00:00 2001
From: Hennadii Stepanov <32963518+hebasto@users.noreply.github.com>
Date: Wed, 26 Jun 2024 22:14:16 +0100
Subject: [PATCH 8/8] cmake: Run secp256k1 tests

---
 src/CMakeLists.txt | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 9558674fe3f56..74ee36c6054c2 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -47,6 +47,11 @@ set(SECP256K1_DISABLE_SHARED ON CACHE BOOL "" FORCE)
 set(SECP256K1_ENABLE_MODULE_ECDH OFF CACHE BOOL "" FORCE)
 set(SECP256K1_ENABLE_MODULE_RECOVERY ON CACHE BOOL "" FORCE)
 set(SECP256K1_ECMULT_GEN_KB 86 CACHE STRING "" FORCE)
+set(SECP256K1_BUILD_BENCHMARK OFF CACHE BOOL "" FORCE)
+set(SECP256K1_BUILD_TESTS ${BUILD_TESTS} CACHE BOOL "" FORCE)
+set(SECP256K1_BUILD_EXHAUSTIVE_TESTS ${BUILD_TESTS} CACHE BOOL "" FORCE)
+set(SECP256K1_BUILD_CTIME_TESTS OFF CACHE BOOL "" FORCE)
+set(SECP256K1_BUILD_EXAMPLES OFF CACHE BOOL "" FORCE)
 include(GetTargetInterface)
 # -fsanitize and related flags apply to both C++ and C,
 # so we can pass them down to libsecp256k1 as CFLAGS.
@@ -62,7 +67,7 @@ foreach(config IN LISTS CMAKE_BUILD_TYPE CMAKE_CONFIGURATION_TYPES)
   string(TOUPPER "${config}" config)
   set(CMAKE_C_FLAGS_${config} "${CMAKE_C_FLAGS_RELWITHDEBINFO}")
 endforeach()
-add_subdirectory(secp256k1 EXCLUDE_FROM_ALL)
+add_subdirectory(secp256k1)
 set_target_properties(secp256k1 PROPERTIES EXPORT_COMPILE_COMMANDS OFF)
 string(APPEND CMAKE_C_COMPILE_OBJECT " ${APPEND_CPPFLAGS} ${APPEND_CFLAGS}")