1 files changed, 3 insertions, 0 deletions
diff --git a/source/slang/syntax.h b/source/slang/syntax.h
index ebb9d814b..00f7eb95b 100644
--- a/source/slang/syntax.h
+++ b/source/slang/syntax.h
@@ -77,6 +77,9 @@ namespace Slang
         // a vector (this will be added to the cost, if any, of converting
         // the element type of the vector)
         kConversionCost_ScalarToVector = 1,
+
+        // Conversion is impossible
+        kConversionCost_Impossible = 0xFFFFFFFF,
     };
 
     // TODO(tfoley): We should ditch this enumeration