...

CMakeLists.txt

@@ -48,6 +48,8 @@ if(USE_SPDLOG)
     set(SPDLOG_USE_STD_FORMAT ON CACHE INTERNAL "Use of C++20 std::format")
     set(SPDLOG_FMT_EXTERNAL OFF CACHE INTERNAL "Turn off external fmt library")
 
+    set(USE_SPDLOG_SYSTEM OFF)
+
     find_package(spdlog CONFIG)
     if(NOT ${spdlog_FOUND})
         message(STATUS "\tfetch spdlog-lib ...")
@@ -62,7 +64,10 @@ if(USE_SPDLOG)
             "-DSPDLOG_USE_STD_FORMAT=ON -DSPDLOG_FMT_EXTERNAL=OFF"
             OVERRIDE_FIND_PACKAGE
         )
+
         find_package(spdlog REQUIRED CONFIG)
+
+        set(USE_SPDLOG_SYSTEM ON)
     endif()
 endif()
 
@@ -152,6 +157,8 @@ endif()
 if(USE_ASIO)
     pkg_check_modules(ASIOLIB IMPORTED_TARGET GLOBAL asio)
 
+    set(USE_ASIO_SYSTEM ON)
+
     if(NOT ASIOLIB_FOUND)
         message(STATUS "\tfetch asio-lib ...")
 
@@ -165,7 +172,6 @@ if(USE_ASIO)
         )
 
         FetchContent_MakeAvailable(asiolib_project)
-    endif()
 
         execute_process(
             WORKING_DIRECTORY ${asiolib_project_SOURCE_DIR}/asio
@@ -181,6 +187,10 @@ if(USE_ASIO)
         pkg_check_modules(ASIOLIB IMPORTED_TARGET GLOBAL asio)
 
         message(STATUS "ASIO INC PATHS: ${ASIOLIB_INCLUDE_DIRS}")
+
+        set(USE_ASIO_SYSTEM OFF)
+
+    endif()
 endif()
 
 if(USE_BSPLINE_PCM)
@@ -254,7 +264,7 @@ if(USE_ASIO)
 endif()
 
 if(USE_SPDLOG)
-    target_link_libraries(${PROJECT_NAME} INTERFACE spdlog::spdlog)
+    target_link_libraries(${PROJECT_NAME} INTERFACE spdlog::spdlog_header_only)
 endif()
 
 if(BUILD_TESTS)