diff --git a/src/os.cpp b/src/os.cpp
index 1085913b1671166e950c2d394043833cc76b3f15..fb6beca8d10a9b842d464381e53f98349489f345 100644
--- a/src/os.cpp
+++ b/src/os.cpp
@@ -973,7 +973,6 @@ void os_stderr_set_color(TermColor color) {
         }
     }
 
-    DWORD chars_written;
     switch (color) {
         case TermColorRed:
             SetConsoleTextAttribute(stderr_handle, FOREGROUND_RED|FOREGROUND_INTENSITY);