Merge #72: Make mpgen target independent from multiprocess one

665d1fd Make `mpgen` target independent from `multiprocess` one (Hennadii Stepanov)

Pull request description:

  Instead of dependency `mpgen` on `multiprocess`, both of them can share the `util` object library.

  This is a step towards ability to build and install `mpgen` and `multiprocess` independently, especially when [cross](bitcoin/bitcoin#25941) building.

ACKs for top commit:
  ryanofsky:
    Code review ACK 665d1fd. I like this change. No reason the code generator and runtime need to share all the same dependencies.

Tree-SHA512: 3194f66a0a62c7ec006ba4894ded2489da2fe08371d69eb9b74e210e3499c1231944690b3509955ef2e8d25ae0c9e88301ae8164732077b5236003f7b2e0627e

Author: ryanofsky

CMakeLists.txt

@@ -49,6 +49,11 @@ cmake_pop_check_state()
 
 capnp_generate_cpp(MP_PROXY_SRCS MP_PROXY_HDRS include/mp/proxy.capnp)
 
+add_library(util OBJECT src/mp/util.cpp)
+target_include_directories(util PRIVATE
+  $<BUILD_INTERFACE:${CMAKE_SOURCE_DIR}/include>
+  $<BUILD_INTERFACE:${CMAKE_BINARY_DIR}/include>)
+
 set(MP_PUBLIC_HEADERS
   ${MP_PROXY_HDRS}
   include/mp/proxy-io.h
@@ -61,7 +66,7 @@ add_library(multiprocess STATIC
   ${MP_PROXY_SRCS}
   ${MP_PUBLIC_HEADERS}
   src/mp/proxy.cpp
-  src/mp/util.cpp)
+  $<TARGET_OBJECTS:util>)
 target_include_directories(multiprocess PUBLIC
   $<BUILD_INTERFACE:${CMAKE_CURRENT_BINARY_DIR}/include>
   $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/include>
@@ -76,15 +81,14 @@ set_target_properties(multiprocess PROPERTIES
     PUBLIC_HEADER "${MP_PUBLIC_HEADERS}")
 install(TARGETS multiprocess EXPORT Multiprocess ARCHIVE DESTINATION lib PUBLIC_HEADER DESTINATION include/mp)
 
-add_executable(mpgen src/mp/gen.cpp)
+add_executable(mpgen src/mp/gen.cpp $<TARGET_OBJECTS:util>)
 target_include_directories(mpgen PRIVATE $<BUILD_INTERFACE:${CMAKE_CURRENT_BINARY_DIR}/include>)
 target_include_directories(mpgen PUBLIC $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/include> $<INSTALL_INTERFACE:include>)
 target_link_libraries(mpgen PRIVATE CapnProto::capnp)
 target_link_libraries(mpgen PRIVATE CapnProto::capnp-rpc)
 target_link_libraries(mpgen PRIVATE CapnProto::capnpc)
 target_link_libraries(mpgen PRIVATE CapnProto::kj)
 target_link_libraries(mpgen PRIVATE Threads::Threads)
-target_link_libraries(mpgen PRIVATE multiprocess)
 set_target_properties(mpgen PROPERTIES
     INSTALL_RPATH_USE_LINK_PATH TRUE)
 install(TARGETS mpgen EXPORT Multiprocess RUNTIME DESTINATION bin)