Add support to clang-cl driver for /GS switch

Summary:
This patch is adding command-line support for the MSVC buffer security check.

The buffer security check is turned on with the '/GS' compiler switch.
https://msdn.microsoft.com/en-us/library/8dbf701c.aspx

The MSVC buffer security check in implemented here:
http://reviews.llvm.org/D20346

Reviewers: hans, rnk

Subscribers: chrisha, cfe-commits, rnk, hans, thakis

Differential Revision: http://reviews.llvm.org/D20347

llvm-svn: 272832

1 files changed, 13 insertions, 0 deletions

diff --git a/clang/lib/Driver/Tools.cpp b/clang/lib/Driver/Tools.cpp
index e73c22d..4ee7714 100644
--- a/clang/lib/Driver/Tools.cpp
+++ b/clang/lib/Driver/Tools.cpp
@@ -6183,6 +6183,14 @@ void Clang::AddClangCLArgs(const ArgList &Args, types::ID InputType,
                    /*default=*/false))
     CmdArgs.push_back("-fno-rtti-data");
 
+  // This controls whether or not we emit stack-protector instrumentation.
+  // In MSVC, Buffer Security Check (/GS) is on by default.
+  if (Args.hasFlag(options::OPT__SLASH_GS, options::OPT__SLASH_GS_,
+                   /*default=*/true)) {
+    CmdArgs.push_back("-stack-protector");
+    CmdArgs.push_back(Args.MakeArgString(Twine(LangOptions::SSPStrong)));
+  }
+
   // Emit CodeView if -Z7 is present.
   *EmitCodeView = Args.hasArg(options::OPT__SLASH_Z7);
   if (*EmitCodeView)
@@ -10022,6 +10030,11 @@ std::unique_ptr<Command> visualstudio::Compiler::GetCommand(
   if (Args.hasFlag(options::OPT__SLASH_GR_, options::OPT__SLASH_GR,
                    /*default=*/false))
     CmdArgs.push_back("/GR-");
+
+  if (Args.hasFlag(options::OPT__SLASH_GS_, options::OPT__SLASH_GS,
+                   /*default=*/false))
+    CmdArgs.push_back("/GS-");
+
   if (Arg *A = Args.getLastArg(options::OPT_ffunction_sections,
                                options::OPT_fno_function_sections))
     CmdArgs.push_back(A->getOption().getID() == options::OPT_ffunction_sections