Merge #1239: cmake: Bugfix and other improvements after bumping CMake…

… up to 3.13

a273d74 cmake: Improve version comparison (Hennadii Stepanov)
6a58b48 cmake: Use `if(... IN_LIST ...)` command (Hennadii Stepanov)
2445808 cmake: Use dedicated `GENERATOR_IS_MULTI_CONFIG` property (Hennadii Stepanov)
9f8703e cmake: Use dedicated `CMAKE_HOST_APPLE` variable (Hennadii Stepanov)
8c20170 cmake: Use recommended `add_compile_definitions` command (Hennadii Stepanov)
04d4cc0 cmake: Add `DESCRIPTION` and `HOMEPAGE_URL` options to `project` command (Hennadii Stepanov)
8a8b653 cmake: Use `SameMinorVersion` compatibility mode (Hennadii Stepanov)

Pull request description:

  This PR:
  - resolves two items from #1235, including a bugfix with package version compatibility
  - includes other improvements which have become available for CMake 3.13+.

  To test the `GENERATOR_IS_MULTI_CONFIG` property on Linux, one can use the "[Ninja Multi-Config](https://cmake.org/cmake/help/latest/generator/Ninja%20Multi-Config.html)" generator:
  ```sh
  cmake -S . -B build -G "Ninja Multi-Config"
  ```

ACKs for top commit:
  real-or-random:
    ACK a273d74
  theuni:
    ACK a273d74

Tree-SHA512: f31c4f0f30bf368303e70ab8952cde5cc8c70a5e79a04f879abcbee3d0a8d8c598379fb38f5142cb1f8ff5f9dcfc8b8eb4c13c975a1d05fdcc92d9c805a59d9a

CMakeLists.txt

@@ -1,16 +1,21 @@
 cmake_minimum_required(VERSION 3.13)
 
-if(CMAKE_VERSION VERSION_GREATER 3.14)
+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()
 
-# 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.
-project(libsecp256k1 VERSION 0.3.2 LANGUAGES C)
+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 0.3.2
+  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
+)
 
 # The library version is based on libtool versioning of the ABI. The set of
 # rules for updating the version can be found here:
@@ -36,27 +41,27 @@ option(SECP256K1_INSTALL "Enable installation" ON)
 
 option(SECP256K1_ENABLE_MODULE_ECDH "Enable ECDH module." ON)
 if(SECP256K1_ENABLE_MODULE_ECDH)
-  add_definitions(-DENABLE_MODULE_ECDH=1)
+  add_compile_definitions(ENABLE_MODULE_ECDH=1)
 endif()
 
 option(SECP256K1_ENABLE_MODULE_RECOVERY "Enable ECDSA pubkey recovery module." OFF)
 if(SECP256K1_ENABLE_MODULE_RECOVERY)
-  add_definitions(-DENABLE_MODULE_RECOVERY=1)
+  add_compile_definitions(ENABLE_MODULE_RECOVERY=1)
 endif()
 
 option(SECP256K1_ENABLE_MODULE_EXTRAKEYS "Enable extrakeys module." ON)
 option(SECP256K1_ENABLE_MODULE_SCHNORRSIG "Enable schnorrsig module." ON)
 if(SECP256K1_ENABLE_MODULE_SCHNORRSIG)
   set(SECP256K1_ENABLE_MODULE_EXTRAKEYS ON)
-  add_definitions(-DENABLE_MODULE_SCHNORRSIG=1)
+  add_compile_definitions(ENABLE_MODULE_SCHNORRSIG=1)
 endif()
 if(SECP256K1_ENABLE_MODULE_EXTRAKEYS)
-  add_definitions(-DENABLE_MODULE_EXTRAKEYS=1)
+  add_compile_definitions(ENABLE_MODULE_EXTRAKEYS=1)
 endif()
 
 option(SECP256K1_USE_EXTERNAL_DEFAULT_CALLBACKS "Enable external default callback functions." OFF)
 if(SECP256K1_USE_EXTERNAL_DEFAULT_CALLBACKS)
-  add_definitions(-DUSE_EXTERNAL_DEFAULT_CALLBACKS=1)
+  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]")
@@ -66,22 +71,22 @@ check_string_option_value(SECP256K1_ECMULT_WINDOW_SIZE)
 if(SECP256K1_ECMULT_WINDOW_SIZE STREQUAL "AUTO")
   set(SECP256K1_ECMULT_WINDOW_SIZE 15)
 endif()
-add_definitions(-DECMULT_WINDOW_SIZE=${SECP256K1_ECMULT_WINDOW_SIZE})
+add_compile_definitions(ECMULT_WINDOW_SIZE=${SECP256K1_ECMULT_WINDOW_SIZE})
 
 set(SECP256K1_ECMULT_GEN_PREC_BITS "AUTO" CACHE STRING "Precision bits to tune the precomputed table size for signing, specified as integer 2, 4 or 8. \"AUTO\" is a reasonable setting for desktop machines (currently 4). [default=AUTO]")
 set_property(CACHE SECP256K1_ECMULT_GEN_PREC_BITS PROPERTY STRINGS "AUTO" 2 4 8)
 check_string_option_value(SECP256K1_ECMULT_GEN_PREC_BITS)
 if(SECP256K1_ECMULT_GEN_PREC_BITS STREQUAL "AUTO")
   set(SECP256K1_ECMULT_GEN_PREC_BITS 4)
 endif()
-add_definitions(-DECMULT_GEN_PREC_BITS=${SECP256K1_ECMULT_GEN_PREC_BITS})
+add_compile_definitions(ECMULT_GEN_PREC_BITS=${SECP256K1_ECMULT_GEN_PREC_BITS})
 
 set(SECP256K1_TEST_OVERRIDE_WIDE_MULTIPLY "OFF" CACHE STRING "Test-only override of the (autodetected by the C code) \"widemul\" setting. Legal values are: \"OFF\", \"int128_struct\", \"int128\" or \"int64\". [default=OFF]")
 set_property(CACHE SECP256K1_TEST_OVERRIDE_WIDE_MULTIPLY PROPERTY STRINGS "OFF" "int128_struct" "int128" "int64")
 check_string_option_value(SECP256K1_TEST_OVERRIDE_WIDE_MULTIPLY)
 if(SECP256K1_TEST_OVERRIDE_WIDE_MULTIPLY)
   string(TOUPPER "${SECP256K1_TEST_OVERRIDE_WIDE_MULTIPLY}" widemul_upper_value)
-  add_definitions(-DUSE_FORCE_WIDEMUL_${widemul_upper_value}=1)
+  add_compile_definitions(USE_FORCE_WIDEMUL_${widemul_upper_value}=1)
 endif()
 mark_as_advanced(FORCE SECP256K1_TEST_OVERRIDE_WIDE_MULTIPLY)
 
@@ -90,13 +95,13 @@ set_property(CACHE SECP256K1_ASM PROPERTY STRINGS "AUTO" "OFF" "x86_64" "arm")
 check_string_option_value(SECP256K1_ASM)
 if(SECP256K1_ASM STREQUAL "arm")
   enable_language(ASM)
-  add_definitions(-DUSE_EXTERNAL_ASM=1)
+  add_compile_definitions(USE_EXTERNAL_ASM=1)
 elseif(SECP256K1_ASM)
   include(Check64bitAssembly)
   check_64bit_assembly()
   if(HAS_64BIT_ASM)
     set(SECP256K1_ASM "x86_64")
-    add_definitions(-DUSE_ASM_X86_64=1)
+    add_compile_definitions(USE_ASM_X86_64=1)
   elseif(SECP256K1_ASM STREQUAL "AUTO")
     set(SECP256K1_ASM "OFF")
   else()
@@ -119,7 +124,7 @@ if(SECP256K1_VALGRIND)
   if(Valgrind_FOUND)
     set(SECP256K1_VALGRIND ON)
     include_directories(${Valgrind_INCLUDE_DIR})
-    add_definitions(-DVALGRIND)
+    add_compile_definitions(VALGRIND)
   elseif(SECP256K1_VALGRIND STREQUAL "AUTO")
     set(SECP256K1_VALGRIND OFF)
   else()
@@ -166,21 +171,24 @@ mark_as_advanced(
   CMAKE_SHARED_LINKER_FLAGS_COVERAGE
 )
 
-if(CMAKE_CONFIGURATION_TYPES)
-  set(CMAKE_CONFIGURATION_TYPES "RelWithDebInfo" "Release" "Debug" "MinSizeRel" "Coverage")
-endif()
-
-get_property(cached_cmake_build_type CACHE CMAKE_BUILD_TYPE PROPERTY TYPE)
-if(cached_cmake_build_type)
+get_property(is_multi_config GLOBAL PROPERTY GENERATOR_IS_MULTI_CONFIG)
+set(default_build_type "RelWithDebInfo")
+if(is_multi_config)
+  set(CMAKE_CONFIGURATION_TYPES "${default_build_type}" "Release" "Debug" "MinSizeRel" "Coverage" CACHE STRING
+    "Supported configuration types."
+    FORCE
+  )
+else()
   set_property(CACHE CMAKE_BUILD_TYPE PROPERTY
-    STRINGS "RelWithDebInfo" "Release" "Debug" "MinSizeRel" "Coverage"
+    STRINGS "${default_build_type}" "Release" "Debug" "MinSizeRel" "Coverage"
   )
-endif()
-
-set(default_build_type "RelWithDebInfo")
-if(NOT CMAKE_BUILD_TYPE AND NOT CMAKE_CONFIGURATION_TYPES)
-  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)
+  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()
 
 include(TryAddCompileOption)
@@ -274,15 +282,15 @@ message("CFLAGS ................................ ${CMAKE_C_FLAGS}")
 get_directory_property(compile_options COMPILE_OPTIONS)
 string(REPLACE ";" " " compile_options "${compile_options}")
 message("Compile options ....................... " ${compile_options})
-if(DEFINED CMAKE_BUILD_TYPE)
+if(NOT is_multi_config)
   message("Build type:")
   message(" - CMAKE_BUILD_TYPE ................... ${CMAKE_BUILD_TYPE}")
   string(TOUPPER "${CMAKE_BUILD_TYPE}" build_type)
   message(" - CFLAGS ............................. ${CMAKE_C_FLAGS_${build_type}}")
   message(" - LDFLAGS for executables ............ ${CMAKE_EXE_LINKER_FLAGS_${build_type}}")
   message(" - LDFLAGS for shared libraries ....... ${CMAKE_SHARED_LINKER_FLAGS_${build_type}}")
 else()
-  message("Available configurations .............. ${CMAKE_CONFIGURATION_TYPES}")
+  message("Supported configurations .............. ${CMAKE_CONFIGURATION_TYPES}")
   message("RelWithDebInfo configuration:")
   message(" - CFLAGS ............................. ${CMAKE_C_FLAGS_RELWITHDEBINFO}")
   message(" - LDFLAGS for executables ............ ${CMAKE_EXE_LINKER_FLAGS_RELWITHDEBINFO}")

cmake/CheckStringOptionValue.cmake

@@ -1,11 +1,9 @@
 function(check_string_option_value option)
   get_property(expected_values CACHE ${option} PROPERTY STRINGS)
   if(expected_values)
-    foreach(value IN LISTS expected_values)
-      if(value STREQUAL "${${option}}")
-        return()
-      endif()
-    endforeach()
+    if(${option} IN_LIST expected_values)
+      return()
+    endif()
     message(FATAL_ERROR "${option} value is \"${${option}}\", but must be one of ${expected_values}.")
   endif()
   message(AUTHOR_WARNING "The STRINGS property must be set before invoking `check_string_option_value' function.")

cmake/FindValgrind.cmake

@@ -1,4 +1,4 @@
-if(CMAKE_HOST_SYSTEM_NAME STREQUAL "Darwin")
+if(CMAKE_HOST_APPLE)
   find_program(BREW_COMMAND brew)
   execute_process(
     COMMAND ${BREW_COMMAND} --prefix valgrind

src/CMakeLists.txt

@@ -114,7 +114,7 @@ if(SECP256K1_INSTALL)
     NO_SET_AND_CHECK_MACRO
   )
   write_basic_package_version_file(${PROJECT_NAME}-config-version.cmake
-    COMPATIBILITY SameMajorVersion
+    COMPATIBILITY SameMinorVersion
   )
 
   install(