diff --git a/dmd/mars.h b/dmd/mars.h
index ac6a72ea..3dc5f193 100644
--- a/dmd/mars.h
+++ b/dmd/mars.h
@@ -182,7 +182,7 @@ struct Param
     bool useSwitchError; // check for switches without a default
     bool useUnitTests;  // generate unittest code
     bool useInline;     // inline expand functions
-    bool warnings;      // enable warnings
+    ubyte warnings;     // enable warnings
     ubyte Dversion;     // D version number
                         // 1: warnings as errors
                         // 2: informational warnings (no errors)