Add some more PS4 driver settings related to rtti and exceptions.

Summary:
The PS4 defaults to -fno-rtti, and has to have rtti enabled when enabling
exceptions.

This commit makes clang add the -fno-rtti by default on the PS4, unless
-frtti was passed in.

It also diagnoses misuses for the PS4:
- Exceptions need rtti. Warn and enable rtti if no rtti flag was passed,
  error if -fno-rtti was passed.

I also added a more general warning for when -fno-rtti is the default
(currently it's only on the PS4) and the vptr sanitizer is on.

Fixed a few tests, due to different flag order when passing cc1 arguments.

Reviewers: chandlerc

Subscribers: cfe-commits

Differential Revision: http://reviews.llvm.org/D7250

llvm-svn: 227518

1 files changed, 37 insertions, 9 deletions

diff --git a/clang/lib/Driver/Tools.cpp b/clang/lib/Driver/Tools.cpp
index 2258f69..91cf841 100644
--- a/clang/lib/Driver/Tools.cpp
+++ b/clang/lib/Driver/Tools.cpp
@@ -3956,20 +3956,48 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA,
                    false))
     CmdArgs.push_back("-fno-elide-constructors");
 
-  // -frtti is default.
-  if (!Args.hasFlag(options::OPT_frtti, options::OPT_fno_rtti) ||
+  // -frtti is default, except for the PS4 CPU.
+  if (!Args.hasFlag(options::OPT_frtti, options::OPT_fno_rtti,
+                    !Triple.isPS4CPU()) ||
       KernelOrKext) {
-    CmdArgs.push_back("-fno-rtti");
+    bool RTTIEnabled = false;
+    Arg *NoRTTIArg = Args.getLastArg(
+        options::OPT_mkernel, options::OPT_fapple_kext, options::OPT_fno_rtti);
+
+    // PS4 requires rtti when exceptions are enabled. If -fno-rtti was
+    // explicitly passed, error out. Otherwise enable rtti and emit a
+    // warning.
+    if (Triple.isPS4CPU()) {
+      if (Arg *A = Args.getLastArg(options::OPT_fcxx_exceptions,
+                                   options::OPT_fexceptions)) {
+        if (NoRTTIArg)
+          D.Diag(diag::err_drv_argument_not_allowed_with)
+              << NoRTTIArg->getAsString(Args) << A->getAsString(Args);
+        else {
+          RTTIEnabled = true;
+          D.Diag(diag::warn_drv_enabling_rtti_with_exceptions);
+        }
+      }
+    }
 
     // -fno-rtti cannot usefully be combined with -fsanitize=vptr.
     if (Sanitize.sanitizesVptr()) {
-      std::string NoRttiArg =
-        Args.getLastArg(options::OPT_mkernel,
-                        options::OPT_fapple_kext,
-                        options::OPT_fno_rtti)->getAsString(Args);
-      D.Diag(diag::err_drv_argument_not_allowed_with)
-        << "-fsanitize=vptr" << NoRttiArg;
+      // If rtti was explicitly disabled and the vptr sanitizer is on, error
+      // out. Otherwise, warn that vptr will be disabled unless -frtti is
+      // passed.
+      if (NoRTTIArg) {
+        D.Diag(diag::err_drv_argument_not_allowed_with)
+            << "-fsanitize=vptr" << NoRTTIArg->getAsString(Args);
+      } else {
+        D.Diag(diag::warn_drv_disabling_vptr_no_rtti_default);
+        // All sanitizer switches have been pushed. This -fno-sanitize
+        // will override any -fsanitize={vptr,undefined} passed before it.
+        CmdArgs.push_back("-fno-sanitize=vptr");
+      }
     }
+
+    if (!RTTIEnabled)
+      CmdArgs.push_back("-fno-rtti");
   }
 
   // -fshort-enums=0 is default for all architectures except Hexagon.