Merge #17: build: Add CMake-based build system (7 of N)

a933ddf [FIXUP] Better document a workaround (Hennadii Stepanov)
769633e [FIXUP] for "cmake: Add wallet functionality" (Hennadii Stepanov)
31e4e62 [FIXUP] for "cmake: Build `test_bitcoin` executable" (Hennadii Stepanov)
f2dbb17 [FIXUP] for "cmake: Build `test_bitcoin` executable" (Hennadii Stepanov)
91d7327 [FIXUP] Boost (Hennadii Stepanov)

Pull request description:

  The parent PR: bitcoin#25797.
  The previous PRs in the staging branch: #5, #6, #7, #10, #13, #15.

  This PR consists of fixups only to make reviewing easier :)

ACKs for top commit:
  theuni:
    ACK a933ddf

Tree-SHA512: 270869a3bf9b9f2d56b75d169f25032385fa2d1297951a23c0d1900d9668a40b153c7a5d9b51fa87596eec681107c40da8e55f405d28a7ecd2ec0f72f3550bbf

cmake/module/AddBoostIfNeeded.cmake

@@ -21,11 +21,35 @@ function(add_boost_if_needed)
   find_package(Boost 1.64.0 REQUIRED)
   set_target_properties(Boost::boost PROPERTIES IMPORTED_GLOBAL TRUE)
   target_compile_definitions(Boost::boost INTERFACE
-    $<$<CONFIG:Debug>:BOOST_MULTI_INDEX_ENABLE_SAFE_MODE>
+    # We don't use multi_index serialization.
+    BOOST_MULTI_INDEX_DISABLE_SERIALIZATION
   )
   if(CMAKE_VERSION VERSION_LESS 3.15)
     add_library(Boost::headers ALIAS Boost::boost)
   endif()
 
+  if(BUILD_TESTS)
+    include(CheckCXXSourceCompiles)
+    set(CMAKE_REQUIRED_INCLUDES ${Boost_INCLUDE_DIR})
+    check_cxx_source_compiles("
+      #define BOOST_TEST_MAIN
+      #include <boost/test/included/unit_test.hpp>
+      " HAVE_BOOST_INCLUDED_UNIT_TEST_H
+    )
+    if(NOT HAVE_BOOST_INCLUDED_UNIT_TEST_H)
+      message(FATAL_ERROR "Building test_bitcoin executable requested but boost/test/included/unit_test.hpp header not available.")
+    endif()
+
+    check_cxx_source_compiles("
+      #define BOOST_TEST_MAIN
+      #include <boost/test/included/unit_test.hpp>
+      #include <boost/test/unit_test.hpp>
+      " HAVE_BOOST_UNIT_TEST_H
+    )
+    if(NOT HAVE_BOOST_UNIT_TEST_H)
+      message(FATAL_ERROR "Building test_bitcoin executable requested but boost/test/unit_test.hpp header not available.")
+    endif()
+  endif()
+
   mark_as_advanced(Boost_INCLUDE_DIR)
 endfunction()

cmake/module/CrossPkgConfig.cmake

@@ -5,6 +5,24 @@
 find_package(PkgConfig REQUIRED)
 
 function(remove_isystem_from_include_directories_internal target)
+  #[=[
+  A workaround for https://gitlab.kitware.com/cmake/cmake/-/issues/20652.
+
+  When the pkg-config provides CFLAGS with -isystem options, for instance:
+
+    $ pkg-config --cflags-only-I libzmq
+    -isystem /usr/include/mit-krb5 -I/usr/include/pgm-5.3 -I/usr/include/libxml2
+
+  an old CMake fails to parse them properly and the INTERFACE_INCLUDE_DIRECTORIES
+  property contains "-isystem" as a separated element:
+
+    -isystem;/usr/include/mit-krb5;/usr/include/pgm-5.3;/usr/include/libxml2
+
+  which ends with an error "Imported target includes non-existent path".
+
+  Fixing by removing the "-isystem" element from the INTERFACE_INCLUDE_DIRECTORIES.
+  ]=]
+
   get_target_property(include_directories ${target} INTERFACE_INCLUDE_DIRECTORIES)
   if(include_directories)
     list(REMOVE_ITEM include_directories -isystem)
@@ -25,7 +43,6 @@ macro(cross_pkg_check_modules prefix)
     pkg_check_modules(${prefix} ${ARGN})
   endif()
 
-  # A workaround for https://gitlab.kitware.com/cmake/cmake/-/issues/20652.
   if(CMAKE_VERSION VERSION_LESS 3.17.3 AND TARGET PkgConfig::${prefix})
     remove_isystem_from_include_directories_internal(PkgConfig::${prefix})
   endif()

cmake/optional.cmake

@@ -111,9 +111,16 @@ endif()
 
 if(ENABLE_WALLET)
   if(WITH_SQLITE)
-    include(CrossPkgConfig)
-    cross_pkg_check_modules(sqlite sqlite3>=3.7.17 IMPORTED_TARGET)
-    if(sqlite_FOUND)
+    # TODO: Consider using the FindSQLite3 module after bumping
+    # the minimum required CMake version up to 3.14+.
+    if(MSVC)
+      # Use of the `unofficial::` namespace is a vcpkg package manager convention.
+      find_package(unofficial-sqlite3 CONFIG)
+    else()
+      include(CrossPkgConfig)
+      cross_pkg_check_modules(sqlite3 sqlite3>=3.7.17 IMPORTED_TARGET)
+    endif()
+    if(TARGET unofficial::sqlite3::sqlite3 OR TARGET PkgConfig::sqlite3)
       set(WITH_SQLITE ON)
       set(USE_SQLITE ON)
     elseif(WITH_SQLITE STREQUAL "AUTO")

src/test/compilerbug_tests.cpp

@@ -6,6 +6,13 @@
 
 BOOST_AUTO_TEST_SUITE(compilerbug_tests)
 
+// At least one test case is required to avoid the "Test setup error: no test
+// cases matching filter or all test cases were disabled" errror.
+BOOST_AUTO_TEST_CASE(dummy)
+{
+    BOOST_CHECK(true);
+}
+
 #if defined(__GNUC__)
 // This block will also be built under clang, which is fine (as it supports noinline)
 void __attribute__ ((noinline)) set_one(unsigned char* ptr)

src/wallet/CMakeLists.txt

@@ -44,7 +44,11 @@ if(NOT USE_SQLITE AND NOT USE_BDB)
 endif()
 if(USE_SQLITE)
   target_sources(bitcoin_wallet PRIVATE sqlite.cpp)
-  target_link_libraries(bitcoin_wallet PRIVATE PkgConfig::sqlite)
+  target_link_libraries(bitcoin_wallet
+    PRIVATE
+      $<TARGET_NAME_IF_EXISTS:unofficial::sqlite3::sqlite3>
+      $<TARGET_NAME_IF_EXISTS:PkgConfig::sqlite3>
+  )
 endif()
 if(USE_BDB)
   target_sources(bitcoin_wallet PRIVATE bdb.cpp salvage.cpp)