2 files changed, 22 insertions, 0 deletions
diff --git a/clang/lib/Frontend/CompilerInvocation.cpp b/clang/lib/Frontend/CompilerInvocation.cpp
index 6b2df349f8b..3406c324645 100644
--- a/clang/lib/Frontend/CompilerInvocation.cpp
+++ b/clang/lib/Frontend/CompilerInvocation.cpp
@@ -1625,6 +1625,8 @@ void CompilerInvocation::setLangDefaults(LangOptions &Opts, InputKind IK,
   Opts.GNUKeywords = Opts.GNUMode;
   Opts.CXXOperatorNames = Opts.CPlusPlus;
 
+  Opts.AlignedAllocation = Opts.CPlusPlus1z;
+
   Opts.DollarIdents = !Opts.AsmPreprocessor;
 }
 
@@ -1937,6 +1939,17 @@ static void ParseLangArgs(LangOptions &Opts, ArgList &Args, InputKind IK,
     getAllNoBuiltinFuncValues(Args, Opts.NoBuiltinFuncs);
   Opts.NoMathBuiltin = Args.hasArg(OPT_fno_math_builtin);
   Opts.SizedDeallocation = Args.hasArg(OPT_fsized_deallocation);
+  Opts.AlignedAllocation =
+      Args.hasFlag(OPT_faligned_allocation, OPT_fno_aligned_allocation,
+                   Opts.AlignedAllocation);
+  Opts.NewAlignOverride =
+      getLastArgIntValue(Args, OPT_fnew_alignment_EQ, 0, Diags);
+  if (Opts.NewAlignOverride && !llvm::isPowerOf2_32(Opts.NewAlignOverride)) {
+    Arg *A = Args.getLastArg(OPT_fnew_alignment_EQ);
+    Diags.Report(diag::err_fe_invalid_alignment) << A->getAsString(Args)
+                                                 << A->getValue();
+    Opts.NewAlignOverride = 0;
+  }
   Opts.ConceptsTS = Args.hasArg(OPT_fconcepts_ts);
   Opts.HeinousExtensions = Args.hasArg(OPT_fheinous_gnu_extensions);
   Opts.AccessControl = !Args.hasArg(OPT_fno_access_control);
diff --git a/clang/lib/Frontend/InitPreprocessor.cpp b/clang/lib/Frontend/InitPreprocessor.cpp
index 7d15e4cd589..d7dccb1340b 100644
--- a/clang/lib/Frontend/InitPreprocessor.cpp
+++ b/clang/lib/Frontend/InitPreprocessor.cpp
@@ -392,6 +392,15 @@ static void InitializeStandardPredefinedMacros(const TargetInfo &TI,
     //   C++ translation unit.
     else
       Builder.defineMacro("__cplusplus", "199711L");
+
+    // C++1z [cpp.predefined]p1:
+    //   An integer literal of type std::size_t whose value is the alignment
+    //   guaranteed by a call to operator new(std::size_t)
+    //
+    // We provide this in all language modes, since it seems generally useful.
+    Builder.defineMacro("__STDCPP_DEFAULT_NEW_ALIGNMENT__",
+                        Twine(TI.getNewAlign() / TI.getCharWidth()) +
+                            TI.getTypeConstantSuffix(TI.getSizeType()));
   }
 
   // In C11 these are environment macros. In C++11 they are only defined