diff --git a/clang/include/clang/Driver/Options.td b/clang/include/clang/Driver/Options.td
--- a/clang/include/clang/Driver/Options.td
+++ b/clang/include/clang/Driver/Options.td
@@ -1720,7 +1720,7 @@
 def ftrivial_auto_var_init : Joined<["-"], "ftrivial-auto-var-init=">, Group<f_Group>,
   Flags<[CC1Option, CoreOption]>, HelpText<"Initialize trivial automatic stack variables: uninitialized (default)"
   " | pattern">, Values<"uninitialized,pattern">;
-def enable_trivial_var_init_zero : Joined<["-"], "enable-trivial-auto-var-init-zero-knowing-it-will-be-removed-from-clang">,
+def enable_trivial_var_init_zero : Flag<["-"], "enable-trivial-auto-var-init-zero-knowing-it-will-be-removed-from-clang">,
   Flags<[CC1Option, CoreOption]>,
   HelpText<"Trivial automatic variable initialization to zero is only here for benchmarks, it'll eventually be removed, and I'm OK with that because I'm only using it to benchmark">;
 def fstandalone_debug : Flag<["-"], "fstandalone-debug">, Group<f_Group>, Flags<[CoreOption]>,