Add driver arguments -ftemplate-depth=N and -fconstexpr-depth=N, with the same

semantics and defaults as the corresponding g++ arguments. The historical g++
argument -ftemplate-depth-N is kept for compatibility, but modern g++ versions
no longer document that option.

Add -cc1 argument -fconstexpr-depth N to implement the corresponding
functionality.

The -ftemplate-depth=N part of this fixes PR9890.

llvm-svn: 145045

1 files changed, 7 insertions, 1 deletions

diff --git a/clang/lib/Frontend/CompilerInvocation.cpp b/clang/lib/Frontend/CompilerInvocation.cpp
index 738facf0695..34080908c0d 100644
--- a/clang/lib/Frontend/CompilerInvocation.cpp
+++ b/clang/lib/Frontend/CompilerInvocation.cpp
@@ -789,6 +789,10 @@ static void LangOptsToArgs(const LangOptions &Opts,
     Res.push_back("-ftemplate-depth");
     Res.push_back(llvm::utostr(Opts.InstantiationDepth));
   }
+  if (Opts.ConstexprCallDepth != DefaultLangOpts.ConstexprCallDepth) {
+    Res.push_back("-fconstexpr-depth");
+    Res.push_back(llvm::utostr(Opts.ConstexprCallDepth));
+  }
   if (!Opts.ObjCConstantStringClass.empty()) {
     Res.push_back("-fconstant-string-class");
     Res.push_back(Opts.ObjCConstantStringClass);
@@ -1777,7 +1781,9 @@ static void ParseLangArgs(LangOptions &Opts, ArgList &Args, InputKind IK,
   Opts.ElideConstructors = !Args.hasArg(OPT_fno_elide_constructors);
   Opts.MathErrno = Args.hasArg(OPT_fmath_errno);
   Opts.InstantiationDepth = Args.getLastArgIntValue(OPT_ftemplate_depth, 1024,
-                                               Diags);
+                                                    Diags);
+  Opts.ConstexprCallDepth = Args.getLastArgIntValue(OPT_fconstexpr_depth, 512,
+                                                    Diags);
   Opts.DelayedTemplateParsing = Args.hasArg(OPT_fdelayed_template_parsing);
   Opts.NumLargeByValueCopy = Args.getLastArgIntValue(OPT_Wlarge_by_value_copy,
                                                     0, Diags);