revert changes that are moved to another PR

Author: Bill-hbrhbr

CMake/ystdlib-cpp-helpers.cmake

@@ -89,12 +89,6 @@ function(cpp_library)
 
     check_if_header_only(arg_cpp_lib_PRIVATE_SOURCES _IS_INTERFACE_LIB _)
     if(_IS_INTERFACE_LIB)
-        if(arg_cpp_lib_PRIVATE_LINK_LIBRARIES)
-            message(
-                FATAL_ERROR
-                "Private dependency specifications disabled for interface library target ${_ALIAS_TARGET_NAME}."
-            )
-        endif()
         add_library(${arg_cpp_lib_NAME} INTERFACE)
         target_include_directories(
             ${arg_cpp_lib_NAME}
@@ -118,16 +112,17 @@ function(cpp_library)
             PUBLIC
                 "$<BUILD_INTERFACE:${arg_cpp_lib_BUILD_INCLUDE_DIR}>"
         )
-        target_link_libraries(
-            ${arg_cpp_lib_NAME}
-            PUBLIC
-                ${arg_cpp_lib_PUBLIC_LINK_LIBRARIES}
-            PRIVATE
-                ${arg_cpp_lib_PRIVATE_LINK_LIBRARIES}
-        )
         target_compile_features(${arg_cpp_lib_NAME} PUBLIC cxx_std_20)
     endif()
 
+	target_link_libraries(
+		${arg_cpp_lib_NAME}
+		PUBLIC
+			${arg_cpp_lib_PUBLIC_LINK_LIBRARIES}
+		PRIVATE
+			${arg_cpp_lib_PRIVATE_LINK_LIBRARIES}
+	)
+
     add_library(${_ALIAS_TARGET_NAME} ALIAS ${arg_cpp_lib_NAME})
 
     if(YSTDLIB_CPP_ENABLE_TESTS)