diff --git a/lib/Sema/Sema.cpp b/lib/Sema/Sema.cpp
index 951856d..38063ac 100644
--- a/lib/Sema/Sema.cpp
+++ b/lib/Sema/Sema.cpp
@@ -665,6 +665,10 @@
     if (IsExprValueWithinWidth(S.Context, E, TargetWidth))
       return;
 
+    // People want to build with -Wshorten-64-to-32 and not -Wconversion
+    // and by god we'll let them.
+    if (SourceWidth == 64 && TargetWidth == 32)
+      return DiagnoseImpCast(S, E, T, diag::warn_impcast_integer_64_32);
     return DiagnoseImpCast(S, E, T, diag::warn_impcast_integer_precision);
   }