5 files changed, 26 insertions, 0 deletions
diff --git a/clang/include/clang/Driver/ToolChain.h b/clang/include/clang/Driver/ToolChain.h
index a43ee107512..953229c0bdf 100644
--- a/clang/include/clang/Driver/ToolChain.h
+++ b/clang/include/clang/Driver/ToolChain.h
@@ -283,6 +283,9 @@ public:
   virtual void addClangTargetOptions(const llvm::opt::ArgList &DriverArgs,
                                      llvm::opt::ArgStringList &CC1Args) const;
 
+  /// \brief Add warning options that need to be passed to cc1 for this target.
+  virtual void addClangWarningOptions(llvm::opt::ArgStringList &CC1Args) const;
+
   // GetRuntimeLibType - Determine the runtime library type to use with the
   // given compilation arguments.
   virtual RuntimeLibType
diff --git a/clang/lib/Driver/ToolChain.cpp b/clang/lib/Driver/ToolChain.cpp
index 6172296b630..d164edd7347 100644
--- a/clang/lib/Driver/ToolChain.cpp
+++ b/clang/lib/Driver/ToolChain.cpp
@@ -250,6 +250,8 @@ void ToolChain::addClangTargetOptions(const ArgList &DriverArgs,
                                       ArgStringList &CC1Args) const {
 }
 
+void ToolChain::addClangWarningOptions(ArgStringList &CC1Args) const {}
+
 ToolChain::RuntimeLibType ToolChain::GetRuntimeLibType(
   const ArgList &Args) const
 {
diff --git a/clang/lib/Driver/ToolChains.cpp b/clang/lib/Driver/ToolChains.cpp
index 4bb8332ea7d..3cf3311de5b 100644
--- a/clang/lib/Driver/ToolChains.cpp
+++ b/clang/lib/Driver/ToolChains.cpp
@@ -242,6 +242,20 @@ DarwinClang::DarwinClang(const Driver &D, const llvm::Triple& Triple,
     getProgramPaths().push_back(getDriver().Dir);
 }
 
+void DarwinClang::addClangWarningOptions(ArgStringList &CC1Args) const {
+  // For iOS, 64-bit, promote certain warnings to errors.
+  if (!isTargetMacOS() && getTriple().isArch64Bit()) {
+    // Always enable -Wdeprecated-objc-isa-usage and promote it
+    // to an error.
+    CC1Args.push_back("-Wdeprecated-objc-isa-usage");
+    CC1Args.push_back("-Werror=deprecated-objc-isa-usage");
+
+    // Also error about implicit function declarations, as that
+    // can impact calling conventions.
+    CC1Args.push_back("-Werror=implicit-function-declaration");
+  }
+}
+
 /// \brief Determine whether Objective-C automated reference counting is
 /// enabled.
 static bool isObjCAutoRefCount(const ArgList &Args) {
diff --git a/clang/lib/Driver/ToolChains.h b/clang/lib/Driver/ToolChains.h
index 529dcbed787..ef90c2ab68d 100644
--- a/clang/lib/Driver/ToolChains.h
+++ b/clang/lib/Driver/ToolChains.h
@@ -488,6 +488,8 @@ public:
   AddCCKextLibArgs(const llvm::opt::ArgList &Args,
                    llvm::opt::ArgStringList &CmdArgs) const override;
 
+  virtual void addClangWarningOptions(llvm::opt::ArgStringList &CC1Args) const;
+
   void
   AddLinkARCArgs(const llvm::opt::ArgList &Args,
                  llvm::opt::ArgStringList &CmdArgs) const override;
diff --git a/clang/lib/Driver/Tools.cpp b/clang/lib/Driver/Tools.cpp
index 9a31eb9f9d6..0c397584d93 100644
--- a/clang/lib/Driver/Tools.cpp
+++ b/clang/lib/Driver/Tools.cpp
@@ -2116,6 +2116,11 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA,
   std::string TripleStr = getToolChain().ComputeEffectiveClangTriple(Args);
   CmdArgs.push_back(Args.MakeArgString(TripleStr));
 
+  // Push all default warning arguments that are specific to
+  // the given target.  These come before user provided warning options
+  // are provided.
+  getToolChain().addClangWarningOptions(CmdArgs);
+
   // Select the appropriate action.
   RewriteKind rewriteKind = RK_None;