diff --git a/reactos/cmake/msvc.cmake b/reactos/cmake/msvc.cmake
index ff82dfab108..99d10f7a18b 100644
--- a/reactos/cmake/msvc.cmake
+++ b/reactos/cmake/msvc.cmake
@@ -343,9 +343,9 @@ macro(add_asm_files _target)
         get_directory_property(_defines COMPILE_DEFINITIONS)
         foreach(_source_file ${ARGN})
             get_filename_component(_source_file_base_name ${_source_file} NAME_WE)
+            get_filename_component(_source_file_full_path ${_source_file} ABSOLUTE)
             set(_preprocessed_asm_file ${CMAKE_CURRENT_BINARY_DIR}/asm/${_source_file_base_name}_${_target}.tmp)
             set(_object_file ${CMAKE_CURRENT_BINARY_DIR}/asm/${_source_file_base_name}_${_target}.obj)
-            set(_source_file_full_path ${CMAKE_CURRENT_SOURCE_DIR}/${_source_file})
             get_source_file_property(_defines_semicolon_list ${_source_file_full_path} COMPILE_DEFINITIONS)
             unset(_source_file_defines)
             foreach(_define ${_defines_semicolon_list})