Index: include/clang/Frontend/CompilerInvocation.h
===================================================================
--- include/clang/Frontend/CompilerInvocation.h
+++ include/clang/Frontend/CompilerInvocation.h
@@ -153,8 +153,10 @@
   ///
   /// \param Opts - The LangOptions object to set up.
   /// \param IK - The input language.
+  /// \param T - The target triple.
   /// \param LangStd - The input language standard.
   static void setLangDefaults(LangOptions &Opts, InputKind IK,
+                   const llvm::Triple &T,
                    LangStandard::Kind LangStd = LangStandard::lang_unspecified);
   
   /// \brief Retrieve a module hash string that is suitable for uniquely 
Index: lib/Frontend/CompilerInvocation.cpp
===================================================================
--- lib/Frontend/CompilerInvocation.cpp
+++ lib/Frontend/CompilerInvocation.cpp
@@ -1344,6 +1344,7 @@
 }
 
 void CompilerInvocation::setLangDefaults(LangOptions &Opts, InputKind IK,
+                                         const llvm::Triple &T,
                                          LangStandard::Kind LangStd) {
   // Set some properties which depend solely on the input kind; it would be nice
   // to move these to the language standard, and have the driver resolve the
@@ -1376,7 +1377,11 @@
     case IK_PreprocessedC:
     case IK_ObjC:
     case IK_PreprocessedObjC:
-      LangStd = LangStandard::lang_gnu11;
+      // The PS4 uses C99 as the default C standard.
+      if (T.isPS4())
+        LangStd = LangStandard::lang_gnu99;
+      else
+        LangStd = LangStandard::lang_gnu11;
       break;
     case IK_CXX:
     case IK_PreprocessedCXX:
@@ -1530,7 +1535,8 @@
       LangStd = OpenCLLangStd;
   }
 
-  CompilerInvocation::setLangDefaults(Opts, IK, LangStd);
+  llvm::Triple T(TargetOpts.Triple);
+  CompilerInvocation::setLangDefaults(Opts, IK, T, LangStd);
 
   // We abuse '-f[no-]gnu-keywords' to force overriding all GNU-extension
   // keywords. This behavior is provided by GCC's poorly named '-fasm' flag,
@@ -1852,7 +1858,6 @@
   // Provide diagnostic when a given target is not expected to be an OpenMP
   // device or host.
   if (Opts.OpenMP && !Opts.OpenMPIsDevice) {
-    llvm::Triple T(TargetOpts.Triple);
     switch (T.getArch()) {
     default:
       break;
Index: test/FixIt/fixit-errors.c
===================================================================
--- test/FixIt/fixit-errors.c
+++ test/FixIt/fixit-errors.c
@@ -22,6 +22,8 @@
   (void)get_origin->x; // expected-error {{base of member reference is a function; perhaps you meant to call it with no arguments?}}
 }
 
+// These errors require C11.
+#if __STDC_VERSION__ > 199901L
 void noreturn_1() _Noreturn; // expected-error {{must precede function declarator}}
 void noreturn_1() {
   return; // expected-warning {{should not return}}
@@ -29,3 +31,4 @@
 void noreturn_2() _Noreturn { // expected-error {{must precede function declarator}}
   return; // expected-warning {{should not return}}
 }
+#endif
Index: test/Preprocessor/init.c
===================================================================
--- test/Preprocessor/init.c
+++ test/Preprocessor/init.c
@@ -88,7 +88,6 @@
 // COMMON:#define __ORDER_LITTLE_ENDIAN__ 1234
 // COMMON:#define __ORDER_PDP_ENDIAN__ 3412
 // COMMON:#define __STDC_HOSTED__ 1
-// COMMON:#define __STDC_VERSION__ 201112L
 // COMMON:#define __STDC__ 1
 // COMMON:#define __VERSION__ {{.*}}
 // COMMON:#define __clang__ 1
@@ -98,7 +97,13 @@
 // COMMON:#define __clang_version__ {{.*}}
 // COMMON:#define __llvm__ 1
 //
+// RUN: %clang_cc1 -E -dM -triple=x86_64-pc-win32 < /dev/null | FileCheck -match-full-lines -check-prefix C-DEFAULT %s
+// RUN: %clang_cc1 -E -dM -triple=x86_64-pc-linux-gnu < /dev/null | FileCheck -match-full-lines -check-prefix C-DEFAULT %s
+// RUN: %clang_cc1 -E -dM -triple=x86_64-apple-darwin < /dev/null | FileCheck -match-full-lines -check-prefix C-DEFAULT %s
+// RUN: %clang_cc1 -E -dM -triple=armv7a-apple-darwin < /dev/null | FileCheck -match-full-lines -check-prefix C-DEFAULT %s
 // 
+// C-DEFAULT:#define __STDC_VERSION__ 201112L
+//
 // RUN: %clang_cc1 -ffreestanding -E -dM < /dev/null | FileCheck -match-full-lines -check-prefix FREESTANDING %s
 // FREESTANDING:#define __STDC_HOSTED__ 0
 //
@@ -8361,6 +8366,7 @@
 // PS4:#define __SSE2__ 1
 // PS4:#define __SSE_MATH__ 1
 // PS4:#define __SSE__ 1
+// PS4:#define __STDC_VERSION__ 199901L
 // PS4:#define __UINTMAX_TYPE__ long unsigned int
 // PS4:#define __USER_LABEL_PREFIX__
 // PS4:#define __WCHAR_MAX__ 65535
Index: test/Sema/attr-deprecated.c
===================================================================
--- test/Sema/attr-deprecated.c
+++ test/Sema/attr-deprecated.c
@@ -122,5 +122,10 @@
 };
 
 typedef int test23_ty __attribute((deprecated));
+// Redefining a typedef is a C11 feature.
+#if __STDC_VERSION__ <= 199901L
+// expected-note@-3 {{'test23_ty' has been explicitly marked deprecated here}}
+#else
 typedef int test23_ty; // expected-note {{'test23_ty' has been explicitly marked deprecated here}}
+#endif
 test23_ty test23_v; // expected-warning {{'test23_ty' is deprecated}}
Index: test/Sema/nullability.c
===================================================================
--- test/Sema/nullability.c
+++ test/Sema/nullability.c
@@ -8,7 +8,11 @@
 typedef int * int_ptr;
 
 // Parse nullability type specifiers.
-typedef int * _Nonnull nonnull_int_ptr; // expected-note{{'_Nonnull' specified here}}
+// This note requires C11.
+#if __STDC_VERSION__ > 199901L
+// expected-note@+2{{'_Nonnull' specified here}}
+#endif
+typedef int * _Nonnull nonnull_int_ptr;
 typedef int * _Nullable nullable_int_ptr;
 typedef int * _Null_unspecified null_unspecified_int_ptr;
 
@@ -23,9 +27,14 @@
 typedef nonnull_int_ptr _Nonnull redundant_okay_1;
 
 // Conflicting nullability specifiers via a typedef are not.
+// Some of these errors require C11.
+#if __STDC_VERSION__ > 199901L
 typedef nonnull_int_ptr _Nullable conflicting_2; // expected-error{{nullability specifier '_Nullable' conflicts with existing specifier '_Nonnull'}}
+#endif
 typedef nonnull_int_ptr nonnull_int_ptr_typedef;
+#if __STDC_VERSION__ > 199901L
 typedef nonnull_int_ptr_typedef _Nullable conflicting_2; // expected-error{{nullability specifier '_Nullable' conflicts with existing specifier '_Nonnull'}}
+#endif
 typedef nonnull_int_ptr_typedef nonnull_int_ptr_typedef_typedef;
 typedef nonnull_int_ptr_typedef_typedef _Null_unspecified conflicting_3; // expected-error{{nullability specifier '_Null_unspecified' conflicts with existing specifier '_Nonnull'}}
 
@@ -69,8 +78,11 @@
 
 // Nullability is not part of the canonical type.
 typedef int * _Nonnull ambiguous_int_ptr;
+// Redefining a typedef is a C11 feature.
+#if __STDC_VERSION__ > 199901L
 typedef int * ambiguous_int_ptr;
 typedef int * _Nullable ambiguous_int_ptr;
+#endif
 
 // Printing of nullability.
 float f;
Index: test/SemaObjC/objcbridge-attribute-arc.m
===================================================================
--- test/SemaObjC/objcbridge-attribute-arc.m
+++ test/SemaObjC/objcbridge-attribute-arc.m
@@ -23,7 +23,10 @@
 
 typedef union __CFUColor __attribute__((objc_bridge(NSUColor))) * CFUColorRef; // expected-error {{parameter of 'objc_bridge' attribute must be 'id' when used on a typedef}}
 
-typedef union __CFUColor __attribute__((objc_bridge(NSUColor))) * CFUColorRef; // expected-error {{parameter of 'objc_bridge' attribute must be 'id' when used on a typedef}}
+// This error requires C11.
+#if __STDC_VERSION__ > 199901L
+typedef union __CFUColor __attribute__((objc_bridge(NSUColor))) * CFUColorRef; // expected-error {{parameter of 'objc_bridge' attribute must be 'id' when used on a typedef}}
+#endif
 
 typedef union __CFUColor __attribute__((objc_bridge(NSUColor))) *CFUColor1Ref; // expected-error {{parameter of 'objc_bridge' attribute must be 'id' when used on a typedef}}