diff --git a/src/mars.c b/src/mars.c
index f5d14cf31a44..4fb4e2d220b0 100644
--- a/src/mars.c
+++ b/src/mars.c
@@ -363,7 +363,7 @@ Usage:\n\
   -o-            do not write object file\n\
   -odobjdir      write object & library files to directory objdir\n\
   -offilename    name output file to filename\n\
-  -op            do not strip paths from source file\n\
+  -op            preserve source path for output files\n\
   -profile       profile runtime performance of generated code\n\
   -property      enforce property syntax\n\
   -quiet         suppress unnecessary messages\n\