diff --git a/CMakeLists.txt b/CMakeLists.txt
index 48b3b18a48..647b99e578 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -65,7 +65,9 @@ add_definitions(-DREACTOS_BINARY_DIR="${REACTOS_BINARY_DIR}")
 
 # There doesn't seem to be a standard for __FILE__ being relative or absolute, so detect it at runtime.
 file(RELATIVE_PATH _PATH_PREFIX ${REACTOS_BINARY_DIR} ${REACTOS_SOURCE_DIR})
-add_compile_flags(-D__RELFILE__="&__FILE__[__FILE__[0] == '.' ? sizeof \\\"${_PATH_PREFIX}\\\" - 1 : sizeof REACTOS_SOURCE_DIR]")
+add_definitions(-DREACTOS_PATH_PREFIX="\\\"${_PATH_PREFIX}\\\"")
+add_definitions(-DREACTOS_FILE_PATH="\\\"${__FILE__}\\\"")
+#add_compile_flags(-D__RELFILE__="&__FILE__[__FILE__[0] == '.' ? sizeof \\\"${_PATH_PREFIX}\\\" - 1 : sizeof REACTOS_SOURCE_DIR]")
 
 if(MSVC_IDE)
     add_compile_flags("/MP")
diff --git a/sdk/include/reactos/debug.h b/sdk/include/reactos/debug.h
index ab332fda18..34a5f9131e 100644
--- a/sdk/include/reactos/debug.h
+++ b/sdk/include/reactos/debug.h
@@ -15,7 +15,16 @@
 #pragma once
 
 #ifndef __RELFILE__
-#define __RELFILE__ __FILE__
+static __inline const char *reactos_relative_path(void)
+{
+    const char *path = REACTOS_FILE_PATH;
+    if (path[0] == '.')
+    {
+        return &path[sizeof(REACTOS_PATH_PREFIX) - 1];
+    }
+    return &path[sizeof(REACTOS_SOURCE_DIR)];
+}
+#define __RELFILE__ reactos_relative_path()
 #endif
 
 /* Define DbgPrint/DbgPrintEx/RtlAssert unless the NDK is used */
diff --git a/sdk/include/reactos/wine/debug.h b/sdk/include/reactos/wine/debug.h
index 35aefc9852..641995647b 100644
--- a/sdk/include/reactos/wine/debug.h
+++ b/sdk/include/reactos/wine/debug.h
@@ -28,7 +28,16 @@
 #endif
 
 #ifndef __RELFILE__
-#define __RELFILE__ __FILE__
+static __inline const char *reactos_relative_path(void)
+{
+    const char *path = REACTOS_FILE_PATH;
+    if (path[0] == '.')
+    {
+        return &path[sizeof(REACTOS_PATH_PREFIX) - 1];
+    }
+    return &path[sizeof(REACTOS_SOURCE_DIR)];
+}
+#define __RELFILE__ reactos_relative_path()
 #endif
 
 #ifdef __WINE_WINE_TEST_H