C++1y: Add a step limit to constexpr evaluation, to catch runaway loops.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@181388 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/clang/Driver/CC1Options.td b/include/clang/Driver/CC1Options.td
index 96a50fc..afe65c47 100644
--- a/include/clang/Driver/CC1Options.td
+++ b/include/clang/Driver/CC1Options.td
@@ -434,6 +434,8 @@
   HelpText<"Maximum depth of recursive template instantiation">;
 def fconstexpr_depth : Separate<["-"], "fconstexpr-depth">,
   HelpText<"Maximum depth of recursive constexpr function calls">;
+def fconstexpr_steps : Separate<["-"], "fconstexpr-steps">,
+  HelpText<"Maximum number of steps in constexpr function evaluation">;
 def fbracket_depth : Separate<["-"], "fbracket-depth">,
   HelpText<"Maximum nesting level for parentheses, brackets, and braces">;
 def fconst_strings : Flag<["-"], "fconst-strings">,