Merge bitcoin/bitcoin#31884: cmake: Make implicit libbitcoinkernel dependencies explicit

3b42e05 cmake: Make implicit `libbitcoinkernel` dependencies explicit (Hennadii Stepanov)
3fd64ef cmake: Avoid using `OBJECT` libraries (Hennadii Stepanov)

Pull request description:

  This PR fixes two regressions introduced in bitcoin/bitcoin#30911.

  For example, on the master branch @ 28dec6c:
  - first regression:
  ```
  $ cmake -B build -G "Ninja" -DBUILD_UTIL_CHAINSTATE=ON -DBUILD_SHARED_LIBS=OFF -DCMAKE_INSTALL_PREFIX=/home/hebasto/INSTALL
  $ cmake --build build -j $(nproc) -t libbitcoinkernel
  $ cmake --install build --component libbitcoinkernel
  - Install configuration: "RelWithDebInfo"
  CMake Error at build/src/kernel/cmake_install.cmake:46 (file):
    file INSTALL cannot find
    "/home/hebasto/dev/bitcoin/build/src/crypto/libbitcoin_crypto.a": No such
    file or directory.
  Call Stack (most recent call first):
    build/src/cmake_install.cmake:172 (include)
    build/cmake_install.cmake:57 (include)

  ```

  - second regression:
  ```
  $ cmake -B build -G "Unix Makefiles" -DBUILD_UTIL_CHAINSTATE=ON -DBUILD_SHARED_LIBS=OFF -DCMAKE_INSTALL_PREFIX=/home/hebasto/INSTALL
  $ cmake --build build -j $(nproc) -t libbitcoinkernel
  ...
  gmake[3]: *** No rule to make target 'src/CMakeFiles/bitcoin_clientversion.dir/clientversion.cpp.o', needed by 'src/kernel/libbitcoinkernel.a'.  Stop.
  gmake[2]: *** [CMakeFiles/Makefile2:1360: src/kernel/CMakeFiles/bitcoinkernel.dir/all] Error 2
  gmake[1]: *** [CMakeFiles/Makefile2:1367: src/kernel/CMakeFiles/bitcoinkernel.dir/rule] Error 2
  gmake: *** [Makefile:647: bitcoinkernel] Error 2
  ```

  With this PR:
  ```
  $ cmake -B build -G "Ninja" -DBUILD_UTIL_CHAINSTATE=ON -DBUILD_SHARED_LIBS=OFF -DCMAKE_INSTALL_PREFIX=/home/hebasto/INSTALL
  $ cmake --build build -j $(nproc) -t libbitcoinkernel
  $ cmake --install build --component libbitcoinkernel
  ```
  and
  ```
  $ cmake -B build -G "Unix Makefiles" -DBUILD_UTIL_CHAINSTATE=ON -DBUILD_SHARED_LIBS=OFF -DCMAKE_INSTALL_PREFIX=/home/hebasto/INSTALL
  $ cmake --build build -j $(nproc) -t libbitcoinkernel
  $ cmake --install build --component libbitcoinkernel
  ```

  ---

  **A note for reviewers:** An alternative approach would be to disable the `OPTIMIZE_DEPENDENCIES` property for the `bitcoinkernel` target. However, I contend that this PR is preferable because (1) it preserves parallel builds for the `libbitcoinkernel` target, and (2) the resulting code has one less workaround for a CMake bug.

ACKs for top commit:
  TheCharlatan:
    ACK 3b42e05
  theuni:
    utACK 3b42e05

Tree-SHA512: 73e9da845688a02e5d61770b7cfd5e1a17440182eb524c7329a47df8f1daa6fe0f9cbde5274832bf43f52e17de86473881dc876dee4276c9c06b173b1b78b7a2

Author: fanquake

src/CMakeLists.txt

@@ -13,7 +13,7 @@ add_custom_target(generate_build_info
   COMMENT "Generating bitcoin-build-info.h"
   VERBATIM
 )
-add_library(bitcoin_clientversion OBJECT EXCLUDE_FROM_ALL
+add_library(bitcoin_clientversion STATIC EXCLUDE_FROM_ALL
   clientversion.cpp
 )
 target_link_libraries(bitcoin_clientversion

src/kernel/CMakeLists.txt

@@ -102,6 +102,10 @@ set_target_properties(bitcoinkernel PROPERTIES
   CXX_VISIBILITY_PRESET default
 )
 
+# Add a convenience libbitcoinkernel target as a synonym for bitcoinkernel.
+add_custom_target(libbitcoinkernel)
+add_dependencies(libbitcoinkernel bitcoinkernel)
+
 # When building the static library, install all static libraries the
 # bitcoinkernel depends on.
 if(NOT BUILD_SHARED_LIBS)
@@ -110,6 +114,7 @@ if(NOT BUILD_SHARED_LIBS)
     get_target_property(linked_libraries ${target} LINK_LIBRARIES)
     foreach(dep ${linked_libraries})
       if(TARGET ${dep})
+        add_dependencies(libbitcoinkernel ${dep})
         get_target_property(dep_type ${dep} TYPE)
         if(dep_type STREQUAL "STATIC_LIBRARY")
           list(APPEND ${libs_out} ${dep})
@@ -132,10 +137,6 @@ endif()
 configure_file(${PROJECT_SOURCE_DIR}/libbitcoinkernel.pc.in ${PROJECT_BINARY_DIR}/libbitcoinkernel.pc @ONLY)
 install(FILES ${PROJECT_BINARY_DIR}/libbitcoinkernel.pc DESTINATION "${CMAKE_INSTALL_LIBDIR}/pkgconfig" COMPONENT libbitcoinkernel)
 
-# Add a convenience libbitcoinkernel target as a synonym for bitcoinkernel.
-add_custom_target(libbitcoinkernel)
-add_dependencies(libbitcoinkernel bitcoinkernel)
-
 install(TARGETS bitcoinkernel
   RUNTIME
     DESTINATION ${CMAKE_INSTALL_BINDIR}

src/util/CMakeLists.txt

@@ -36,9 +36,6 @@ add_library(bitcoin_util STATIC EXCLUDE_FROM_ALL
   ../sync.cpp
 )
 
-# Workaround for https://gitlab.kitware.com/cmake/cmake/-/issues/24058
-set_target_properties(bitcoin_util PROPERTIES OPTIMIZE_DEPENDENCIES OFF)
-
 target_link_libraries(bitcoin_util
   PRIVATE
     core_interface