4 files changed, 20 insertions, 0 deletions
diff --git a/lib/Basic/TargetInfo.cpp b/lib/Basic/TargetInfo.cpp
index 12caf0c8e5..e965b9aec3 100644
--- a/lib/Basic/TargetInfo.cpp
+++ b/lib/Basic/TargetInfo.cpp
@@ -12,6 +12,7 @@
 //===----------------------------------------------------------------------===//
 
 #include "clang/Basic/TargetInfo.h"
+#include "clang/Basic/LangOptions.h"
 #include "llvm/ADT/APFloat.h"
 #include "llvm/ADT/STLExtras.h"
 #include <cstdlib>
@@ -124,6 +125,15 @@ bool TargetInfo::isTypeSigned(IntType T) const {
   };
 }
 
+/// setForcedLangOptions - Set forced language options.
+/// Apply changes to the target information with respect to certain
+/// language options which change the target configuration.
+void TargetInfo::setForcedLangOptions(LangOptions &Opts) {
+	if (Opts.ShortWChar) {
+    WCharType = UnsignedShort;
+    WCharWidth = WCharAlign = 16;
+	}
+}
 
 //===----------------------------------------------------------------------===//
 
diff --git a/lib/Driver/Tools.cpp b/lib/Driver/Tools.cpp
index 808c31c648..c35ad7c5ea 100644
--- a/lib/Driver/Tools.cpp
+++ b/lib/Driver/Tools.cpp
@@ -922,6 +922,13 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA,
       CmdArgs.push_back("-fsigned-char=0");
   }
 
+  // -fshort-wchar default varies depending on platform; only
+  // pass if specified.
+  if (Arg *A = Args.getLastArg(options::OPT_fshort_wchar)) {
+    if (A->getOption().matches(options::OPT_fshort_wchar))
+      CmdArgs.push_back("-fshort-wchar");
+  }
+
   // -fno-pascal-strings is default, only pass non-default. If the tool chain
   // happened to translate to -mpascal-strings, we want to back translate here.
   //
diff --git a/lib/Frontend/PCHReader.cpp b/lib/Frontend/PCHReader.cpp
index 26f426ba32..a812604e39 100644
--- a/lib/Frontend/PCHReader.cpp
+++ b/lib/Frontend/PCHReader.cpp
@@ -104,6 +104,7 @@ PCHValidator::ReadLanguageOptions(const LangOptions &LangOpts) {
   PARSE_LANGOPT_IMPORTANT(NoInline, diag::warn_pch_no_inline);
   PARSE_LANGOPT_IMPORTANT(AccessControl, diag::warn_pch_access_control);
   PARSE_LANGOPT_IMPORTANT(CharIsSigned, diag::warn_pch_char_signed);
+  PARSE_LANGOPT_IMPORTANT(ShortWChar, diag::warn_pch_short_wchar);
   if ((PPLangOpts.getGCMode() != 0) != (LangOpts.getGCMode() != 0)) {
     Reader.Diag(diag::warn_pch_gc_mode)
       << LangOpts.getGCMode() << PPLangOpts.getGCMode();
@@ -1741,6 +1742,7 @@ bool PCHReader::ParseLanguageOptions(
     PARSE_LANGOPT(NoInline);
     PARSE_LANGOPT(AccessControl);
     PARSE_LANGOPT(CharIsSigned);
+    PARSE_LANGOPT(ShortWChar);
     LangOpts.setGCMode((LangOptions::GCMode)Record[Idx]);
     ++Idx;
     LangOpts.setVisibilityMode((LangOptions::VisibilityMode)Record[Idx]);
diff --git a/lib/Frontend/PCHWriter.cpp b/lib/Frontend/PCHWriter.cpp
index de56166125..436428b375 100644
--- a/lib/Frontend/PCHWriter.cpp
+++ b/lib/Frontend/PCHWriter.cpp
@@ -765,6 +765,7 @@ void PCHWriter::WriteLanguageOptions(const LangOptions &LangOpts) {
                                             // be enabled.
   Record.push_back(LangOpts.CharIsSigned); // Whether char is a signed or
                                            // unsigned type
+  Record.push_back(LangOpts.ShortWChar);  // force wchar_t to be unsigned short
   Record.push_back(LangOpts.getGCMode());
   Record.push_back(LangOpts.getVisibilityMode());
   Record.push_back(LangOpts.getStackProtectorMode());