Implement __builtin_LINE() et. al. to support source location capture.

Summary:
This patch implements the source location builtins `__builtin_LINE(), `__builtin_FUNCTION()`, `__builtin_FILE()` and `__builtin_COLUMN()`. These builtins are needed to implement [`std::experimental::source_location`](https://rawgit.com/cplusplus/fundamentals-ts/v2/main.html#reflection.src_loc.creation).

With the exception of `__builtin_COLUMN`, GCC also implements these builtins, and Clangs behavior is intended to match as closely as possible. 

Reviewers: rsmith, joerg, aaron.ballman, bogner, majnemer, shafik, martong

Reviewed By: rsmith

Subscribers: rnkovacs, loskutov, riccibruno, mgorny, kunitoki, alexr, majnemer, hfinkel, cfe-commits

Differential Revision: https://reviews.llvm.org/D37035

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@360937 91177308-0d34-0410-b5e6-96231b3b80d8

docs/LanguageExtensions.rst

@@ -2300,6 +2300,61 @@ automatically will insert one if the first argument to `llvm.coro.suspend` is
 token `none`. If a user calls `__builin_suspend`, clang will insert `token none`
 as the first argument to the intrinsic.
 
+Source location builtins
+------------------------
+
+Clang provides experimental builtins to support C++ standard library implementation
+of ``std::experimental::source_location`` as specified in  http://wg21.link/N4600.
+With the exception of ``__builtin_COLUMN``, these builtins are also implemented by
+GCC.
+
+**Syntax**:
+
+.. code-block:: c
+
+  const char *__builtin_FILE();
+  const char *__builtin_FUNCTION();
+  unsigned    __builtin_LINE();
+  unsigned    __builtin_COLUMN(); // Clang only
+
+**Example of use**:
+
+.. code-block:: c++
+
+  void my_assert(bool pred, int line = __builtin_LINE(), // Captures line of caller
+                 const char* file = __builtin_FILE(),
+                 const char* function = __builtin_FUNCTION()) {
+    if (pred) return;
+    printf("%s:%d assertion failed in function %s\n", file, line, function);
+    std::abort();
+  }
+
+  struct MyAggregateType {
+    int x;
+    int line = __builtin_LINE(); // captures line where aggregate initialization occurs
+  };
+  static_assert(MyAggregateType{42}.line == __LINE__);
+
+  struct MyClassType {
+    int line = __builtin_LINE(); // captures line of the constructor used during initialization
+    constexpr MyClassType(int) { assert(line == __LINE__); }
+  };
+
+**Description**:
+
+The builtins ``__builtin_LINE``, ``__builtin_FUNCTION``, and ``__builtin_FILE`` return
+the values, at the "invocation point", for ``__LINE__``, ``__FUNCTION__``, and
+``__FILE__`` respectively. These builtins are constant expressions.
+
+When the builtins appear as part of a default function argument the invocation
+point is the location of the caller. When the builtins appear as part of a
+default member initializer, the invocation point is the location of the
+constructor or aggregate initialization used to create the object. Otherwise
+the invocation point is the same as the location of the builtin.
+
+When the invocation point of ``__builtin_FUNCTION`` is not a function scope the
+empty string is returned.
+
 Non-standard C++11 Attributes
 =============================
 

include/clang/AST/ASTContext.h

@@ -271,6 +271,12 @@ private:
   llvm::DenseMap<const MaterializeTemporaryExpr *, APValue *>
     MaterializedTemporaryValues;
 
+  /// A cache mapping a string value to a StringLiteral object with the same
+  /// value.
+  ///
+  /// This is lazily created.  This is intentionally not serialized.
+  mutable llvm::StringMap<StringLiteral *> StringLiteralCache;
+
   /// Representation of a "canonical" template template parameter that
   /// is used in canonical template names.
   class CanonicalTemplateTemplateParm : public llvm::FoldingSetNode {
@@ -1323,6 +1329,10 @@ public:
                                 ArrayType::ArraySizeModifier ASM,
                                 unsigned IndexTypeQuals) const;
 
+  /// Return a type for a constant array for a string literal of the
+  /// specified element type and length.
+  QualType getStringLiteralArrayType(QualType EltTy, unsigned Length) const;
+
   /// Returns a vla type where known sizes are replaced with [*].
   QualType getVariableArrayDecayedType(QualType Ty) const;
 
@@ -2805,6 +2815,11 @@ public:
   APValue *getMaterializedTemporaryValue(const MaterializeTemporaryExpr *E,
                                          bool MayCreate);
 
+  /// Return a string representing the human readable name for the specified
+  /// function declaration or file name. Used by SourceLocExpr and
+  /// PredefinedExpr to cache evaluated results.
+  StringLiteral *getPredefinedStringLiteralFromCache(StringRef Key) const;
+
   //===--------------------------------------------------------------------===//
   //                    Statistics
   //===--------------------------------------------------------------------===//

include/clang/AST/CurrentSourceLocExprScope.h

@@ -0,0 +1,75 @@
+//===--- CurrentSourceLocExprScope.h ----------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+//  This file defines types used to track the current context needed to evaluate
+//  a SourceLocExpr.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_AST_CURRENT_SOURCE_LOC_EXPR_SCOPE_H
+#define LLVM_CLANG_AST_CURRENT_SOURCE_LOC_EXPR_SCOPE_H
+
+#include <cassert>
+
+namespace clang {
+class Expr;
+
+/// Represents the current source location and context used to determine the
+/// value of the source location builtins (ex. __builtin_LINE), including the
+/// context of default argument and default initializer expressions.
+class CurrentSourceLocExprScope {
+  /// The CXXDefaultArgExpr or CXXDefaultInitExpr we're currently evaluating.
+  const Expr *DefaultExpr = nullptr;
+
+public:
+  /// A RAII style scope guard used for tracking the current source
+  /// location and context as used by the source location builtins
+  /// (ex. __builtin_LINE).
+  class SourceLocExprScopeGuard;
+
+  const Expr *getDefaultExpr() const { return DefaultExpr; }
+
+  explicit CurrentSourceLocExprScope() = default;
+
+private:
+  explicit CurrentSourceLocExprScope(const Expr *DefaultExpr)
+      : DefaultExpr(DefaultExpr) {}
+
+  CurrentSourceLocExprScope(CurrentSourceLocExprScope const &) = default;
+  CurrentSourceLocExprScope &
+  operator=(CurrentSourceLocExprScope const &) = default;
+};
+
+class CurrentSourceLocExprScope::SourceLocExprScopeGuard {
+public:
+  SourceLocExprScopeGuard(const Expr *DefaultExpr,
+                          CurrentSourceLocExprScope &Current)
+      : Current(Current), OldVal(Current), Enable(false) {
+    assert(DefaultExpr && "the new scope should not be empty");
+    if ((Enable = (Current.getDefaultExpr() == nullptr)))
+      Current = CurrentSourceLocExprScope(DefaultExpr);
+  }
+
+  ~SourceLocExprScopeGuard() {
+    if (Enable)
+      Current = OldVal;
+  }
+
+private:
+  SourceLocExprScopeGuard(SourceLocExprScopeGuard const &) = delete;
+  SourceLocExprScopeGuard &operator=(SourceLocExprScopeGuard const &) = delete;
+
+  CurrentSourceLocExprScope &Current;
+  CurrentSourceLocExprScope OldVal;
+  bool Enable;
+};
+
+} // end namespace clang
+
+#endif // LLVM_CLANG_AST_CURRENT_SOURCE_LOC_EXPR_SCOPE_H

include/clang/AST/Expr.h

@@ -4171,6 +4171,70 @@ public:
   }
 };
 
+/// Represents a function call to one of __builtin_LINE(), __builtin_COLUMN(),
+/// __builtin_FUNCTION(), or __builtin_FILE().
+class SourceLocExpr final : public Expr {
+  SourceLocation BuiltinLoc, RParenLoc;
+  DeclContext *ParentContext;
+
+public:
+  enum IdentKind { Function, File, Line, Column };
+
+  SourceLocExpr(const ASTContext &Ctx, IdentKind Type, SourceLocation BLoc,
+                SourceLocation RParenLoc, DeclContext *Context);
+
+  /// Build an empty call expression.
+  explicit SourceLocExpr(EmptyShell Empty) : Expr(SourceLocExprClass, Empty) {}
+
+  /// Return the result of evaluating this SourceLocExpr in the specified
+  /// (and possibly null) default argument or initialization context.
+  APValue EvaluateInContext(const ASTContext &Ctx,
+                            const Expr *DefaultExpr) const;
+
+  /// Return a string representing the name of the specific builtin function.
+  StringRef getBuiltinStr() const;
+
+  IdentKind getIdentKind() const {
+    return static_cast<IdentKind>(SourceLocExprBits.Kind);
+  }
+
+  bool isStringType() const {
+    switch (getIdentKind()) {
+    case File:
+    case Function:
+      return true;
+    case Line:
+    case Column:
+      return false;
+    }
+  }
+  bool isIntType() const LLVM_READONLY { return !isStringType(); }
+
+  /// If the SourceLocExpr has been resolved return the subexpression
+  /// representing the resolved value. Otherwise return null.
+  const DeclContext *getParentContext() const { return ParentContext; }
+  DeclContext *getParentContext() { return ParentContext; }
+
+  SourceLocation getLocation() const { return BuiltinLoc; }
+  SourceLocation getBeginLoc() const { return BuiltinLoc; }
+  SourceLocation getEndLoc() const { return RParenLoc; }
+
+  child_range children() {
+    return child_range(child_iterator(), child_iterator());
+  }
+
+  const_child_range children() const {
+    return const_child_range(child_iterator(), child_iterator());
+  }
+
+  static bool classof(const Stmt *T) {
+    return T->getStmtClass() == SourceLocExprClass;
+  }
+
+private:
+  friend class ASTStmtReader;
+};
+
 /// Describes an C or C++ initializer list.
 ///
 /// InitListExpr describes an initializer list, which can be used to

include/clang/AST/ExprCXX.h

@@ -1121,7 +1121,11 @@ class CXXDefaultArgExpr final : public Expr {
   /// The parameter whose default is being used.
   ParmVarDecl *Param;
 
-  CXXDefaultArgExpr(StmtClass SC, SourceLocation Loc, ParmVarDecl *Param)
+  /// The context where the default argument expression was used.
+  DeclContext *UsedContext;
+
+  CXXDefaultArgExpr(StmtClass SC, SourceLocation Loc, ParmVarDecl *Param,
+      DeclContext *UsedContext)
       : Expr(SC,
              Param->hasUnparsedDefaultArg()
                  ? Param->getType().getNonReferenceType()
@@ -1129,7 +1133,7 @@ class CXXDefaultArgExpr final : public Expr {
              Param->getDefaultArg()->getValueKind(),
              Param->getDefaultArg()->getObjectKind(), false, false, false,
              false),
-        Param(Param) {
+        Param(Param), UsedContext(UsedContext) {
     CXXDefaultArgExprBits.Loc = Loc;
   }
 
@@ -1139,8 +1143,10 @@ public:
   // \p Param is the parameter whose default argument is used by this
   // expression.
   static CXXDefaultArgExpr *Create(const ASTContext &C, SourceLocation Loc,
-                                   ParmVarDecl *Param) {
-    return new (C) CXXDefaultArgExpr(CXXDefaultArgExprClass, Loc, Param);
+                                   ParmVarDecl *Param,
+                                   DeclContext *UsedContext) {
+    return new (C)
+        CXXDefaultArgExpr(CXXDefaultArgExprClass, Loc, Param, UsedContext);
   }
 
   // Retrieve the parameter that the argument was created from.
@@ -1151,6 +1157,9 @@ public:
   const Expr *getExpr() const { return getParam()->getDefaultArg(); }
   Expr *getExpr() { return getParam()->getDefaultArg(); }
 
+  const DeclContext *getUsedContext() const { return UsedContext; }
+  DeclContext *getUsedContext() { return UsedContext; }
+
   /// Retrieve the location where this default argument was actually used.
   SourceLocation getUsedLocation() const { return CXXDefaultArgExprBits.Loc; }
 
@@ -1190,8 +1199,11 @@ class CXXDefaultInitExpr : public Expr {
   /// The field whose default is being used.
   FieldDecl *Field;
 
+  /// The context where the default initializer expression was used.
+  DeclContext *UsedContext;
+
   CXXDefaultInitExpr(const ASTContext &Ctx, SourceLocation Loc,
-                     FieldDecl *Field, QualType Ty);
+                     FieldDecl *Field, QualType Ty, DeclContext *UsedContext);
 
   CXXDefaultInitExpr(EmptyShell Empty) : Expr(CXXDefaultInitExprClass, Empty) {}
 
@@ -1199,8 +1211,8 @@ public:
   /// \p Field is the non-static data member whose default initializer is used
   /// by this expression.
   static CXXDefaultInitExpr *Create(const ASTContext &Ctx, SourceLocation Loc,
-                                    FieldDecl *Field) {
-    return new (Ctx) CXXDefaultInitExpr(Ctx, Loc, Field, Field->getType());
+                                    FieldDecl *Field, DeclContext *UsedContext) {
+    return new (Ctx) CXXDefaultInitExpr(Ctx, Loc, Field, Field->getType(), UsedContext);
   }
 
   /// Get the field whose initializer will be used.
@@ -1217,6 +1229,13 @@ public:
     return Field->getInClassInitializer();
   }
 
+  const DeclContext *getUsedContext() const { return UsedContext; }
+  DeclContext *getUsedContext() { return UsedContext; }
+
+  /// Retrieve the location where this default initializer expression was
+  /// actually used.
+  SourceLocation getUsedLocation() const { return getBeginLoc(); }
+
   SourceLocation getBeginLoc() const { return CXXDefaultInitExprBits.Loc; }
   SourceLocation getEndLoc() const { return CXXDefaultInitExprBits.Loc; }
 

include/clang/AST/RecursiveASTVisitor.h

@@ -2550,6 +2550,8 @@ DEF_TRAVERSE_STMT(PredefinedExpr, {})
 DEF_TRAVERSE_STMT(ShuffleVectorExpr, {})
 DEF_TRAVERSE_STMT(ConvertVectorExpr, {})
 DEF_TRAVERSE_STMT(StmtExpr, {})
+DEF_TRAVERSE_STMT(SourceLocExpr, {})
+
 DEF_TRAVERSE_STMT(UnresolvedLookupExpr, {
   TRY_TO(TraverseNestedNameSpecifierLoc(S->getQualifierLoc()));
   if (S->hasExplicitTemplateArgs()) {

include/clang/AST/Stmt.h

@@ -550,6 +550,17 @@ protected:
     unsigned ResultIndex : 32 - 8 - NumExprBits;
   };
 
+  class SourceLocExprBitfields {
+    friend class ASTStmtReader;
+    friend class SourceLocExpr;
+
+    unsigned : NumExprBits;
+
+    /// The kind of source location builtin represented by the SourceLocExpr.
+    /// Ex. __builtin_LINE, __builtin_FUNCTION, ect.
+    unsigned Kind : 2;
+  };
+
   //===--- C++ Expression bitfields classes ---===//
 
   class CXXOperatorCallExprBitfields {
@@ -935,6 +946,7 @@ protected:
     ParenListExprBitfields ParenListExprBits;
     GenericSelectionExprBitfields GenericSelectionExprBits;
     PseudoObjectExprBitfields PseudoObjectExprBits;
+    SourceLocExprBitfields SourceLocExprBits;
 
     // C++ Expressions
     CXXOperatorCallExprBitfields CXXOperatorCallExprBits;

include/clang/Basic/StmtNodes.td

@@ -96,6 +96,7 @@ def ParenListExpr : DStmt<Expr>;
 def VAArgExpr : DStmt<Expr>;
 def GenericSelectionExpr : DStmt<Expr>;
 def PseudoObjectExpr : DStmt<Expr>;
+def SourceLocExpr : DStmt<Expr>;
 
 // Wrapper expressions
 def FullExpr : DStmt<Expr, 1>;

include/clang/Basic/TokenKinds.def

@@ -404,6 +404,11 @@ KEYWORD(__alignof                   , KEYALL)
 KEYWORD(__attribute                 , KEYALL)
 KEYWORD(__builtin_choose_expr       , KEYALL)
 KEYWORD(__builtin_offsetof          , KEYALL)
+KEYWORD(__builtin_FILE              , KEYALL)
+KEYWORD(__builtin_FUNCTION          , KEYALL)
+KEYWORD(__builtin_LINE              , KEYALL)
+KEYWORD(__builtin_COLUMN            , KEYALL)
+
 // __builtin_types_compatible_p is a GNU C extension that we handle like a C++
 // type trait.
 TYPE_TRAIT_2(__builtin_types_compatible_p, TypeCompatible, KEYNOCXX)

include/clang/Sema/Sema.h

@@ -4612,6 +4612,21 @@ public:
   ExprResult BuildVAArgExpr(SourceLocation BuiltinLoc, Expr *E,
                             TypeSourceInfo *TInfo, SourceLocation RPLoc);
 
+  // __builtin_LINE(), __builtin_FUNCTION(), __builtin_FILE(),
+  // __builtin_COLUMN()
+  ExprResult ActOnSourceLocExpr(SourceLocExpr::IdentKind Kind,
+                                SourceLocation BuiltinLoc,
+                                SourceLocation RPLoc);
+
+  /// Build a potentially resolved SourceLocExpr.
+  ///
+  /// \param SubExpr - null when the SourceLocExpr is unresolved, otherwise
+  /// SubExpr will be a literal expression representing the value of the
+  /// builtin call.
+  ExprResult BuildSourceLocExpr(SourceLocExpr::IdentKind Kind,
+                                SourceLocation BuiltinLoc, SourceLocation RPLoc,
+                                DeclContext *ParentContext);
+
   // __null
   ExprResult ActOnGNUNullExpr(SourceLocation TokenLoc);
 

include/clang/Serialization/ASTBitCodes.h

@@ -1732,6 +1732,9 @@ namespace serialization {
       /// A GNUNullExpr record.
       EXPR_GNU_NULL,
 
+      /// A SourceLocExpr record.
+      EXPR_SOURCE_LOC,
+
       /// A ShuffleVectorExpr record.
       EXPR_SHUFFLE_VECTOR,
 

lib/AST/ASTContext.cpp

@@ -10208,6 +10208,31 @@ ASTContext::getMaterializedTemporaryValue(const MaterializeTemporaryExpr *E,
   return MaterializedTemporaryValues.lookup(E);
 }
 
+QualType ASTContext::getStringLiteralArrayType(QualType EltTy,
+                                               unsigned Length) const {
+  // A C++ string literal has a const-qualified element type (C++ 2.13.4p1).
+  if (getLangOpts().CPlusPlus || getLangOpts().ConstStrings)
+    EltTy = EltTy.withConst();
+
+  EltTy = adjustStringLiteralBaseType(EltTy);
+
+  // Get an array type for the string, according to C99 6.4.5. This includes
+  // the null terminator character.
+  return getConstantArrayType(EltTy, llvm::APInt(32, Length + 1),
+                              ArrayType::Normal, /*IndexTypeQuals*/ 0);
+}
+
+StringLiteral *
+ASTContext::getPredefinedStringLiteralFromCache(StringRef Key) const {
+  StringLiteral *&Result = StringLiteralCache[Key];
+  if (!Result)
+    Result = StringLiteral::Create(
+        *this, Key, StringLiteral::Ascii,
+        /*Pascal*/ false, getStringLiteralArrayType(CharTy, Key.size()),
+        SourceLocation());
+  return Result;
+}
+
 bool ASTContext::AtomicUsesUnsupportedLibcall(const AtomicExpr *E) const {
   const llvm::Triple &T = getTargetInfo().getTriple();
   if (!T.isOSDarwin())

lib/AST/ASTImporter.cpp

@@ -6801,8 +6801,12 @@ ExpectedStmt ASTNodeImporter::VisitCXXDefaultArgExpr(CXXDefaultArgExpr *E) {
   if (!ToParamOrErr)
     return ToParamOrErr.takeError();
 
+  auto UsedContextOrErr = Importer.ImportContext(E->getUsedContext());
+  if (!UsedContextOrErr)
+    return UsedContextOrErr.takeError();
+
   return CXXDefaultArgExpr::Create(
-      Importer.getToContext(), *ToUsedLocOrErr, *ToParamOrErr);
+      Importer.getToContext(), *ToUsedLocOrErr, *ToParamOrErr, *UsedContextOrErr);
 }
 
 ExpectedStmt
@@ -7525,8 +7529,12 @@ ExpectedStmt ASTNodeImporter::VisitCXXDefaultInitExpr(CXXDefaultInitExpr *E) {
   if (!ToFieldOrErr)
     return ToFieldOrErr.takeError();
 
+  auto UsedContextOrErr = Importer.ImportContext(E->getUsedContext());
+  if (!UsedContextOrErr)
+    return UsedContextOrErr.takeError();
+
   return CXXDefaultInitExpr::Create(
-      Importer.getToContext(), *ToBeginLocOrErr, *ToFieldOrErr);
+      Importer.getToContext(), *ToBeginLocOrErr, *ToFieldOrErr, *UsedContextOrErr);
 }
 
 ExpectedStmt ASTNodeImporter::VisitCXXNamedCastExpr(CXXNamedCastExpr *E) {

lib/AST/Expr.cpp

@@ -10,13 +10,14 @@
 //
 //===----------------------------------------------------------------------===//
 
+#include "clang/AST/Expr.h"
+#include "clang/AST/APValue.h"
 #include "clang/AST/ASTContext.h"
 #include "clang/AST/Attr.h"
 #include "clang/AST/DeclCXX.h"
 #include "clang/AST/DeclObjC.h"
 #include "clang/AST/DeclTemplate.h"
 #include "clang/AST/EvaluatedExprVisitor.h"
-#include "clang/AST/Expr.h"
 #include "clang/AST/ExprCXX.h"
 #include "clang/AST/Mangle.h"
 #include "clang/AST/RecordLayout.h"
@@ -1992,6 +1993,91 @@ bool BinaryOperator::isNullPointerArithmeticExtension(ASTContext &Ctx,
 
   return true;
 }
+
+static QualType getDecayedSourceLocExprType(const ASTContext &Ctx,
+                                            SourceLocExpr::IdentKind Kind) {
+  switch (Kind) {
+  case SourceLocExpr::File:
+  case SourceLocExpr::Function: {
+    QualType ArrTy = Ctx.getStringLiteralArrayType(Ctx.CharTy, 0);
+    return Ctx.getPointerType(ArrTy->getAsArrayTypeUnsafe()->getElementType());
+  }
+  case SourceLocExpr::Line:
+  case SourceLocExpr::Column:
+    return Ctx.UnsignedIntTy;
+  }
+  llvm_unreachable("unhandled case");
+}
+
+SourceLocExpr::SourceLocExpr(const ASTContext &Ctx, IdentKind Kind,
+                             SourceLocation BLoc, SourceLocation RParenLoc,
+                             DeclContext *ParentContext)
+    : Expr(SourceLocExprClass, getDecayedSourceLocExprType(Ctx, Kind),
+           VK_RValue, OK_Ordinary, false, false, false, false),
+      BuiltinLoc(BLoc), RParenLoc(RParenLoc), ParentContext(ParentContext) {
+  SourceLocExprBits.Kind = Kind;
+}
+
+StringRef SourceLocExpr::getBuiltinStr() const {
+  switch (getIdentKind()) {
+  case File:
+    return "__builtin_FILE";
+  case Function:
+    return "__builtin_FUNCTION";
+  case Line:
+    return "__builtin_LINE";
+  case Column:
+    return "__builtin_COLUMN";
+  }
+  llvm_unreachable("unexpected IdentKind!");
+}
+
+APValue SourceLocExpr::EvaluateInContext(const ASTContext &Ctx,
+                                         const Expr *DefaultExpr) const {
+  SourceLocation Loc;
+  const DeclContext *Context;
+
+  std::tie(Loc,
+           Context) = [&]() -> std::pair<SourceLocation, const DeclContext *> {
+    if (auto *DIE = dyn_cast_or_null<CXXDefaultInitExpr>(DefaultExpr))
+      return {DIE->getUsedLocation(), DIE->getUsedContext()};
+    if (auto *DAE = dyn_cast_or_null<CXXDefaultArgExpr>(DefaultExpr))
+      return {DAE->getUsedLocation(), DAE->getUsedContext()};
+    return {this->getLocation(), this->getParentContext()};
+  }();
+
+  PresumedLoc PLoc = Ctx.getSourceManager().getPresumedLoc(
+      Ctx.getSourceManager().getExpansionRange(Loc).getEnd());
+
+  auto MakeStringLiteral = [&](StringRef Tmp) {
+    using LValuePathEntry = APValue::LValuePathEntry;
+    StringLiteral *Res = Ctx.getPredefinedStringLiteralFromCache(Tmp);
+    // Decay the string to a pointer to the first character.
+    LValuePathEntry Path[1] = {LValuePathEntry::ArrayIndex(0)};
+    return APValue(Res, CharUnits::Zero(), Path, /*OnePastTheEnd=*/false);
+  };
+
+  switch (getIdentKind()) {
+  case SourceLocExpr::File:
+    return MakeStringLiteral(PLoc.getFilename());
+  case SourceLocExpr::Function: {
+    const Decl *CurDecl = dyn_cast_or_null<Decl>(Context);
+    return MakeStringLiteral(
+        CurDecl ? PredefinedExpr::ComputeName(PredefinedExpr::Function, CurDecl)
+                : std::string(""));
+  }
+  case SourceLocExpr::Line:
+  case SourceLocExpr::Column: {
+    llvm::APSInt IntVal(Ctx.getIntWidth(Ctx.UnsignedIntTy),
+                        /*IsUnsigned=*/true);
+    IntVal = getIdentKind() == SourceLocExpr::Line ? PLoc.getLine()
+                                                   : PLoc.getColumn();
+    return APValue(IntVal);
+  }
+  }
+  llvm_unreachable("unhandled case");
+}
+
 InitListExpr::InitListExpr(const ASTContext &C, SourceLocation lbraceloc,
                            ArrayRef<Expr*> initExprs, SourceLocation rbraceloc)
   : Expr(InitListExprClass, QualType(), VK_RValue, OK_Ordinary, false, false,
@@ -3156,6 +3242,7 @@ bool Expr::HasSideEffects(const ASTContext &Ctx,
   case ObjCAvailabilityCheckExprClass:
   case CXXUuidofExprClass:
   case OpaqueValueExprClass:
+  case SourceLocExprClass:
     // These never have a side-effect.
     return false;
 

lib/AST/ExprCXX.cpp

@@ -907,13 +907,14 @@ const IdentifierInfo *UserDefinedLiteral::getUDSuffix() const {
 }
 
 CXXDefaultInitExpr::CXXDefaultInitExpr(const ASTContext &Ctx, SourceLocation Loc,
-                                       FieldDecl *Field, QualType Ty)
+                                       FieldDecl *Field, QualType Ty,
+                                       DeclContext *UsedContext)
     : Expr(CXXDefaultInitExprClass, Ty.getNonLValueExprType(Ctx),
            Ty->isLValueReferenceType() ? VK_LValue : Ty->isRValueReferenceType()
                                                         ? VK_XValue
                                                         : VK_RValue,
            /*FIXME*/ OK_Ordinary, false, false, false, false),
-      Field(Field) {
+      Field(Field), UsedContext(UsedContext) {
   CXXDefaultInitExprBits.Loc = Loc;
   assert(Field->hasInClassInitializer());
 }

lib/AST/ExprClassification.cpp

@@ -191,6 +191,7 @@ static Cl::Kinds ClassifyInternal(ASTContext &Ctx, const Expr *E) {
   case Expr::ArrayInitIndexExprClass:
   case Expr::NoInitExprClass:
   case Expr::DesignatedInitUpdateExprClass:
+  case Expr::SourceLocExprClass:
     return Cl::CL_PRValue;
 
   case Expr::ConstantExprClass:

lib/AST/ExprConstant.cpp

@@ -37,6 +37,7 @@
 #include "clang/AST/ASTDiagnostic.h"
 #include "clang/AST/ASTLambda.h"
 #include "clang/AST/CharUnits.h"
+#include "clang/AST/CurrentSourceLocExprScope.h"
 #include "clang/AST/CXXInheritance.h"
 #include "clang/AST/Expr.h"
 #include "clang/AST/OSLog.h"
@@ -64,6 +65,9 @@ namespace {
   struct CallStackFrame;
   struct EvalInfo;
 
+  using SourceLocExprScopeGuard =
+      CurrentSourceLocExprScope::SourceLocExprScopeGuard;
+
   static QualType getType(APValue::LValueBase B) {
     if (!B) return QualType();
     if (const ValueDecl *D = B.dyn_cast<const ValueDecl*>()) {
@@ -106,12 +110,12 @@ namespace {
   /// Get an LValue path entry, which is known to not be an array index, as a
   /// field declaration.
   static const FieldDecl *getAsField(APValue::LValuePathEntry E) {
-    return dyn_cast<FieldDecl>(E.getAsBaseOrMember().getPointer());
+    return dyn_cast_or_null<FieldDecl>(E.getAsBaseOrMember().getPointer());
   }
   /// Get an LValue path entry, which is known to not be an array index, as a
   /// base class declaration.
   static const CXXRecordDecl *getAsBaseClass(APValue::LValuePathEntry E) {
-    return dyn_cast<CXXRecordDecl>(E.getAsBaseOrMember().getPointer());
+    return dyn_cast_or_null<CXXRecordDecl>(E.getAsBaseOrMember().getPointer());
   }
   /// Determine whether this LValue path entry for a base class names a virtual
   /// base class.
@@ -464,6 +468,10 @@ namespace {
     /// parameters' function scope indices.
     APValue *Arguments;
 
+    /// Source location information about the default argument or default
+    /// initializer expression we're evaluating, if any.
+    CurrentSourceLocExprScope CurSourceLocExprScope;
+
     // Note that we intentionally use std::map here so that references to
     // values are stable.
     typedef std::pair<const void *, unsigned> MapKeyTy;
@@ -2732,6 +2740,9 @@ static unsigned getBaseIndex(const CXXRecordDecl *Derived,
 /// Extract the value of a character from a string literal.
 static APSInt extractStringLiteralCharacter(EvalInfo &Info, const Expr *Lit,
                                             uint64_t Index) {
+  assert(!isa<SourceLocExpr>(Lit) &&
+         "SourceLocExpr should have already been converted to a StringLiteral");
+
   // FIXME: Support MakeStringConstant
   if (const auto *ObjCEnc = dyn_cast<ObjCEncodeExpr>(Lit)) {
     std::string Str;
@@ -3469,6 +3480,7 @@ static bool handleLValueToRValueConversion(EvalInfo &Info, const Expr *Conv,
 
   // Check for special cases where there is no existing APValue to look at.
   const Expr *Base = LVal.Base.dyn_cast<const Expr*>();
+
   if (Base && !LVal.getLValueCallIndex() && !Type.isVolatileQualified()) {
     if (const CompoundLiteralExpr *CLE = dyn_cast<CompoundLiteralExpr>(Base)) {
       // In C99, a CompoundLiteralExpr is an lvalue, and we defer evaluating the
@@ -5242,6 +5254,7 @@ public:
     { return StmtVisitorTy::Visit(E->getReplacement()); }
   bool VisitCXXDefaultArgExpr(const CXXDefaultArgExpr *E) {
     TempVersionRAII RAII(*Info.CurrentCall);
+    SourceLocExprScopeGuard Guard(E, Info.CurrentCall->CurSourceLocExprScope);
     return StmtVisitorTy::Visit(E->getExpr());
   }
   bool VisitCXXDefaultInitExpr(const CXXDefaultInitExpr *E) {
@@ -5249,8 +5262,10 @@ public:
     // The initializer may not have been parsed yet, or might be erroneous.
     if (!E->getExpr())
       return Error(E);
+    SourceLocExprScopeGuard Guard(E, Info.CurrentCall->CurSourceLocExprScope);
     return StmtVisitorTy::Visit(E->getExpr());
   }
+
   // We cannot create any objects for which cleanups are required, so there is
   // nothing to do here; all cleanups must come from unevaluated subexpressions.
   bool VisitExprWithCleanups(const ExprWithCleanups *E)
@@ -6327,6 +6342,14 @@ public:
     return true;
   }
 
+  bool VisitSourceLocExpr(const SourceLocExpr *E) {
+    assert(E->isStringType() && "SourceLocExpr isn't a pointer type?");
+    APValue LValResult = E->EvaluateInContext(
+        Info.Ctx, Info.CurrentCall->CurSourceLocExprScope.getDefaultExpr());
+    Result.setFrom(Info.Ctx, LValResult);
+    return true;
+  }
+
   // FIXME: Missing: @protocol, @selector
 };
 } // end anonymous namespace
@@ -7982,7 +8005,7 @@ public:
 
   bool VisitCXXNoexceptExpr(const CXXNoexceptExpr *E);
   bool VisitSizeOfPackExpr(const SizeOfPackExpr *E);
-
+  bool VisitSourceLocExpr(const SourceLocExpr *E);
   // FIXME: Missing: array subscript of vector, member of vector
 };
 
@@ -8058,6 +8081,12 @@ static bool EvaluateInteger(const Expr *E, APSInt &Result, EvalInfo &Info) {
   return true;
 }
 
+bool IntExprEvaluator::VisitSourceLocExpr(const SourceLocExpr *E) {
+  APValue Evaluated = E->EvaluateInContext(
+      Info.Ctx, Info.CurrentCall->CurSourceLocExprScope.getDefaultExpr());
+  return Success(Evaluated, E);
+}
+
 static bool EvaluateFixedPoint(const Expr *E, APFixedPoint &Result,
                                EvalInfo &Info) {
   if (E->getType()->isFixedPointType()) {
@@ -11899,7 +11928,7 @@ static ICEDiag CheckICE(const Expr* E, const ASTContext &Ctx) {
 
   case Expr::SizeOfPackExprClass:
   case Expr::GNUNullExprClass:
-    // GCC considers the GNU __null value to be an integral constant expression.
+  case Expr::SourceLocExprClass:
     return NoDiag();
 
   case Expr::SubstNonTypeTemplateParmExprClass:

lib/AST/ItaniumMangle.cpp

@@ -3589,6 +3589,7 @@ recurse:
   case Expr::AsTypeExprClass:
   case Expr::PseudoObjectExprClass:
   case Expr::AtomicExprClass:
+  case Expr::SourceLocExprClass:
   case Expr::FixedPointLiteralClass:
   {
     if (!NullOut) {

lib/AST/StmtPrinter.cpp

@@ -905,6 +905,10 @@ void StmtPrinter::VisitOMPTargetTeamsDistributeSimdDirective(
 //  Expr printing methods.
 //===----------------------------------------------------------------------===//
 
+void StmtPrinter::VisitSourceLocExpr(SourceLocExpr *Node) {
+  OS << Node->getBuiltinStr() << "()";
+}
+
 void StmtPrinter::VisitConstantExpr(ConstantExpr *Node) {
   PrintExpr(Node->getSubExpr());
 }

lib/AST/StmtProfile.cpp

@@ -1882,6 +1882,10 @@ void StmtProfiler::VisitTypoExpr(const TypoExpr *E) {
   VisitExpr(E);
 }
 
+void StmtProfiler::VisitSourceLocExpr(const SourceLocExpr *E) {
+  VisitExpr(E);
+}
+
 void StmtProfiler::VisitObjCStringLiteral(const ObjCStringLiteral *S) {
   VisitExpr(S);
 }

lib/CodeGen/CGExpr.cpp

@@ -1315,11 +1315,15 @@ LValue CodeGenFunction::EmitLValue(const Expr *E) {
     return LV;
   }
 
-  case Expr::CXXDefaultArgExprClass:
-    return EmitLValue(cast<CXXDefaultArgExpr>(E)->getExpr());
+  case Expr::CXXDefaultArgExprClass: {
+    auto *DAE = cast<CXXDefaultArgExpr>(E);
+    CXXDefaultArgExprScope Scope(*this, DAE);
+    return EmitLValue(DAE->getExpr());
+  }
   case Expr::CXXDefaultInitExprClass: {
-    CXXDefaultInitExprScope Scope(*this);
-    return EmitLValue(cast<CXXDefaultInitExpr>(E)->getExpr());
+    auto *DIE = cast<CXXDefaultInitExpr>(E);
+    CXXDefaultInitExprScope Scope(*this, DIE);
+    return EmitLValue(DIE->getExpr());
   }
   case Expr::CXXTypeidExprClass:
     return EmitCXXTypeidLValue(cast<CXXTypeidExpr>(E));

lib/CodeGen/CGExprAgg.cpp

@@ -165,10 +165,11 @@ public:
   void VisitImplicitValueInitExpr(ImplicitValueInitExpr *E);
   void VisitNoInitExpr(NoInitExpr *E) { } // Do nothing.
   void VisitCXXDefaultArgExpr(CXXDefaultArgExpr *DAE) {
+    CodeGenFunction::CXXDefaultArgExprScope Scope(CGF, DAE);
     Visit(DAE->getExpr());
   }
   void VisitCXXDefaultInitExpr(CXXDefaultInitExpr *DIE) {
-    CodeGenFunction::CXXDefaultInitExprScope Scope(CGF);
+    CodeGenFunction::CXXDefaultInitExprScope Scope(CGF, DIE);
     Visit(DIE->getExpr());
   }
   void VisitCXXBindTemporaryExpr(CXXBindTemporaryExpr *E);

lib/CodeGen/CGExprComplex.cpp

@@ -213,10 +213,11 @@ public:
     return Visit(E->getSubExpr());
   }
   ComplexPairTy VisitCXXDefaultArgExpr(CXXDefaultArgExpr *DAE) {
+    CodeGenFunction::CXXDefaultArgExprScope Scope(CGF, DAE);
     return Visit(DAE->getExpr());
   }
   ComplexPairTy VisitCXXDefaultInitExpr(CXXDefaultInitExpr *DIE) {
-    CodeGenFunction::CXXDefaultInitExprScope Scope(CGF);
+    CodeGenFunction::CXXDefaultInitExprScope Scope(CGF, DIE);
     return Visit(DIE->getExpr());
   }
   ComplexPairTy VisitExprWithCleanups(ExprWithCleanups *E) {

lib/CodeGen/CGExprConstant.cpp

@@ -884,10 +884,6 @@ public:
     llvm_unreachable("Invalid CastKind");
   }
 
-  llvm::Constant *VisitCXXDefaultArgExpr(CXXDefaultArgExpr *DAE, QualType T) {
-    return Visit(DAE->getExpr(), T);
-  }
-
   llvm::Constant *VisitCXXDefaultInitExpr(CXXDefaultInitExpr *DIE, QualType T) {
     // No need for a DefaultInitExprScope: we don't handle 'this' in a
     // constant expression.

lib/CodeGen/CGExprScalar.cpp

@@ -16,6 +16,7 @@
 #include "CGObjCRuntime.h"
 #include "CodeGenFunction.h"
 #include "CodeGenModule.h"
+#include "ConstantEmitter.h"
 #include "TargetInfo.h"
 #include "clang/AST/ASTContext.h"
 #include "clang/AST/DeclObjC.h"
@@ -640,12 +641,20 @@ public:
   Value *VisitMaterializeTemporaryExpr(const MaterializeTemporaryExpr *E) {
     return EmitLoadOfLValue(E);
   }
+  Value *VisitSourceLocExpr(SourceLocExpr *SLE) {
+    auto &Ctx = CGF.getContext();
+    APValue Evaluated =
+        SLE->EvaluateInContext(Ctx, CGF.CurSourceLocExprScope.getDefaultExpr());
+    return ConstantEmitter(CGF.CGM, &CGF)
+        .emitAbstract(SLE->getLocation(), Evaluated, SLE->getType());
+  }
 
   Value *VisitCXXDefaultArgExpr(CXXDefaultArgExpr *DAE) {
+    CodeGenFunction::CXXDefaultArgExprScope Scope(CGF, DAE);
     return Visit(DAE->getExpr());
   }
   Value *VisitCXXDefaultInitExpr(CXXDefaultInitExpr *DIE) {
-    CodeGenFunction::CXXDefaultInitExprScope Scope(CGF);
+    CodeGenFunction::CXXDefaultInitExprScope Scope(CGF, DIE);
     return Visit(DIE->getExpr());
   }
   Value *VisitCXXThisExpr(CXXThisExpr *TE) {

lib/CodeGen/CodeGenFunction.h

@@ -22,6 +22,7 @@
 #include "EHScopeStack.h"
 #include "VarBypassDetector.h"
 #include "clang/AST/CharUnits.h"
+#include "clang/AST/CurrentSourceLocExprScope.h"
 #include "clang/AST/ExprCXX.h"
 #include "clang/AST/ExprObjC.h"
 #include "clang/AST/ExprOpenMP.h"
@@ -1393,6 +1394,12 @@ private:
   SourceLocation LastStopPoint;
 
 public:
+  /// Source location information about the default argument or member
+  /// initializer expression we're evaluating, if any.
+  CurrentSourceLocExprScope CurSourceLocExprScope;
+  using SourceLocExprScopeGuard =
+      CurrentSourceLocExprScope::SourceLocExprScopeGuard;
+
   /// A scope within which we are constructing the fields of an object which
   /// might use a CXXDefaultInitExpr. This stashes away a 'this' value to use
   /// if we need to evaluate a CXXDefaultInitExpr within the evaluation.
@@ -1413,11 +1420,12 @@ public:
 
   /// The scope of a CXXDefaultInitExpr. Within this scope, the value of 'this'
   /// is overridden to be the object under construction.
-  class CXXDefaultInitExprScope {
+  class CXXDefaultInitExprScope  {
   public:
-    CXXDefaultInitExprScope(CodeGenFunction &CGF)
-      : CGF(CGF), OldCXXThisValue(CGF.CXXThisValue),
-        OldCXXThisAlignment(CGF.CXXThisAlignment) {
+    CXXDefaultInitExprScope(CodeGenFunction &CGF, const CXXDefaultInitExpr *E)
+        : CGF(CGF), OldCXXThisValue(CGF.CXXThisValue),
+          OldCXXThisAlignment(CGF.CXXThisAlignment),
+          SourceLocScope(E, CGF.CurSourceLocExprScope) {
       CGF.CXXThisValue = CGF.CXXDefaultInitExprThis.getPointer();
       CGF.CXXThisAlignment = CGF.CXXDefaultInitExprThis.getAlignment();
     }
@@ -1430,6 +1438,12 @@ public:
     CodeGenFunction &CGF;
     llvm::Value *OldCXXThisValue;
     CharUnits OldCXXThisAlignment;
+    SourceLocExprScopeGuard SourceLocScope;
+  };
+
+  struct CXXDefaultArgExprScope : SourceLocExprScopeGuard {
+    CXXDefaultArgExprScope(CodeGenFunction &CGF, const CXXDefaultArgExpr *E)
+        : SourceLocExprScopeGuard(E, CGF.CurSourceLocExprScope) {}
   };
 
   /// The scope of an ArrayInitLoopExpr. Within this scope, the value of the

lib/Parse/ParseExpr.cpp

@@ -639,6 +639,10 @@ class CastExpressionIdValidator final : public CorrectionCandidateCallback {
 /// [GNU]   '__builtin_offsetof' '(' type-name ',' offsetof-member-designator')'
 /// [GNU]   '__builtin_choose_expr' '(' assign-expr ',' assign-expr ','
 ///                                     assign-expr ')'
+/// [GNU]   '__builtin_FILE' '(' ')'
+/// [GNU]   '__builtin_FUNCTION' '(' ')'
+/// [GNU]   '__builtin_LINE' '(' ')'
+/// [CLANG] '__builtin_COLUMN' '(' ')'
 /// [GNU]   '__builtin_types_compatible_p' '(' type-name ',' type-name ')'
 /// [GNU]   '__null'
 /// [OBJC]  '[' objc-message-expr ']'
@@ -1106,6 +1110,10 @@ ExprResult Parser::ParseCastExpression(bool isUnaryExpression,
   case tok::kw___builtin_choose_expr:
   case tok::kw___builtin_astype: // primary-expression: [OCL] as_type()
   case tok::kw___builtin_convertvector:
+  case tok::kw___builtin_COLUMN:
+  case tok::kw___builtin_FILE:
+  case tok::kw___builtin_FUNCTION:
+  case tok::kw___builtin_LINE:
     return ParseBuiltinPrimaryExpression();
   case tok::kw___null:
     return Actions.ActOnGNUNullExpr(ConsumeToken());
@@ -2067,6 +2075,10 @@ ExprResult Parser::ParseUnaryExprOrTypeTraitExpression() {
 /// [GNU]   '__builtin_choose_expr' '(' assign-expr ',' assign-expr ','
 ///                                     assign-expr ')'
 /// [GNU]   '__builtin_types_compatible_p' '(' type-name ',' type-name ')'
+/// [GNU]   '__builtin_FILE' '(' ')'
+/// [GNU]   '__builtin_FUNCTION' '(' ')'
+/// [GNU]   '__builtin_LINE' '(' ')'
+/// [CLANG] '__builtin_COLUMN' '(' ')'
 /// [OCL]   '__builtin_astype' '(' assignment-expression ',' type-name ')'
 ///
 /// [GNU] offsetof-member-designator:
@@ -2286,6 +2298,33 @@ ExprResult Parser::ParseBuiltinPrimaryExpression() {
                                          ConsumeParen());
     break;
   }
+  case tok::kw___builtin_COLUMN:
+  case tok::kw___builtin_FILE:
+  case tok::kw___builtin_FUNCTION:
+  case tok::kw___builtin_LINE: {
+    // Attempt to consume the r-paren.
+    if (Tok.isNot(tok::r_paren)) {
+      Diag(Tok, diag::err_expected) << tok::r_paren;
+      SkipUntil(tok::r_paren, StopAtSemi);
+      return ExprError();
+    }
+    SourceLocExpr::IdentKind Kind = [&] {
+      switch (T) {
+      case tok::kw___builtin_FILE:
+        return SourceLocExpr::File;
+      case tok::kw___builtin_FUNCTION:
+        return SourceLocExpr::Function;
+      case tok::kw___builtin_LINE:
+        return SourceLocExpr::Line;
+      case tok::kw___builtin_COLUMN:
+        return SourceLocExpr::Column;
+      default:
+        llvm_unreachable("invalid keyword");
+      }
+    }();
+    Res = Actions.ActOnSourceLocExpr(Kind, StartLoc, ConsumeParen());
+    break;
+  }
   }
 
   if (Res.isInvalid())

lib/Sema/SemaDeclCXX.cpp

@@ -62,7 +62,7 @@ namespace {
 
   public:
     CheckDefaultArgumentVisitor(Expr *defarg, Sema *s)
-      : DefaultArg(defarg), S(s) {}
+        : DefaultArg(defarg), S(s) {}
 
     bool VisitExpr(Expr *Node);
     bool VisitDeclRefExpr(DeclRefExpr *DRE);
@@ -13025,7 +13025,7 @@ ExprResult Sema::BuildCXXDefaultInitExpr(SourceLocation Loc, FieldDecl *Field) {
 
   // If we already have the in-class initializer nothing needs to be done.
   if (Field->getInClassInitializer())
-    return CXXDefaultInitExpr::Create(Context, Loc, Field);
+    return CXXDefaultInitExpr::Create(Context, Loc, Field, CurContext);
 
   // If we might have already tried and failed to instantiate, don't try again.
   if (Field->isInvalidDecl())
@@ -13066,7 +13066,7 @@ ExprResult Sema::BuildCXXDefaultInitExpr(SourceLocation Loc, FieldDecl *Field) {
       Field->setInvalidDecl();
       return ExprError();
     }
-    return CXXDefaultInitExpr::Create(Context, Loc, Field);
+    return CXXDefaultInitExpr::Create(Context, Loc, Field, CurContext);
   }
 
   // DR1351:

lib/Sema/SemaExceptionSpec.cpp

@@ -1289,6 +1289,7 @@ CanThrowResult Sema::canThrow(const Expr *E) {
   case Expr::PredefinedExprClass:
   case Expr::SizeOfPackExprClass:
   case Expr::StringLiteralClass:
+  case Expr::SourceLocExprClass:
     // These expressions can never throw.
     return CT_Cannot;
 

lib/Sema/SemaExpr.cpp

@@ -1683,20 +1683,8 @@ Sema::ActOnStringLiteral(ArrayRef<Token> StringToks, Scope *UDLScope) {
     Diag(RemovalDiagLoc, RemovalDiag);
   }
 
-
-  QualType CharTyConst = CharTy;
-  // A C++ string literal has a const-qualified element type (C++ 2.13.4p1).
-  if (getLangOpts().CPlusPlus || getLangOpts().ConstStrings)
-    CharTyConst.addConst();
-
-  CharTyConst = Context.adjustStringLiteralBaseType(CharTyConst);
-
-  // Get an array type for the string, according to C99 6.4.5.  This includes
-  // the nul terminator character as well as the string length for pascal
-  // strings.
-  QualType StrTy = Context.getConstantArrayType(
-      CharTyConst, llvm::APInt(32, Literal.GetNumStringChars() + 1),
-      ArrayType::Normal, 0);
+  QualType StrTy =
+      Context.getStringLiteralArrayType(CharTy, Literal.GetNumStringChars());
 
   // Pass &StringTokLocs[0], StringTokLocs.size() to factory!
   StringLiteral *Lit = StringLiteral::Create(Context, Literal.GetString(),
@@ -4873,7 +4861,7 @@ ExprResult Sema::BuildCXXDefaultArgExpr(SourceLocation CallLoc,
                                         FunctionDecl *FD, ParmVarDecl *Param) {
   if (CheckCXXDefaultArgExpr(CallLoc, FD, Param))
     return ExprError();
-  return CXXDefaultArgExpr::Create(Context, CallLoc, Param);
+  return CXXDefaultArgExpr::Create(Context, CallLoc, Param, CurContext);
 }
 
 Sema::VariadicCallType
@@ -5138,8 +5126,7 @@ bool Sema::GatherArgumentsForCall(SourceLocation CallLoc, FunctionDecl *FDecl,
     } else {
       assert(Param && "can't use default arguments without a known callee");
 
-      ExprResult ArgExpr =
-        BuildCXXDefaultArgExpr(CallLoc, FDecl, Param);
+      ExprResult ArgExpr = BuildCXXDefaultArgExpr(CallLoc, FDecl, Param);
       if (ArgExpr.isInvalid())
         return true;
 
@@ -14097,6 +14084,20 @@ ExprResult Sema::ActOnGNUNullExpr(SourceLocation TokenLoc) {
   return new (Context) GNUNullExpr(Ty, TokenLoc);
 }
 
+ExprResult Sema::ActOnSourceLocExpr(SourceLocExpr::IdentKind Kind,
+                                    SourceLocation BuiltinLoc,
+                                    SourceLocation RPLoc) {
+  return BuildSourceLocExpr(Kind, BuiltinLoc, RPLoc, CurContext);
+}
+
+ExprResult Sema::BuildSourceLocExpr(SourceLocExpr::IdentKind Kind,
+                                    SourceLocation BuiltinLoc,
+                                    SourceLocation RPLoc,
+                                    DeclContext *ParentContext) {
+  return new (Context)
+      SourceLocExpr(Context, Kind, BuiltinLoc, RPLoc, ParentContext);
+}
+
 bool Sema::ConversionToObjCStringLiteralCheck(QualType DstType, Expr *&Exp,
                                               bool Diagnose) {
   if (!getLangOpts().ObjC)

lib/Sema/SemaExprObjC.cpp

@@ -1097,12 +1097,7 @@ ExprResult Sema::BuildObjCEncodeExpression(SourceLocation AtLoc,
 
     // The type of @encode is the same as the type of the corresponding string,
     // which is an array type.
-    StrTy = Context.CharTy;
-    // A C++ string literal has a const-qualified element type (C++ 2.13.4p1).
-    if (getLangOpts().CPlusPlus || getLangOpts().ConstStrings)
-      StrTy.addConst();
-    StrTy = Context.getConstantArrayType(StrTy, llvm::APInt(32, Str.size()+1),
-                                         ArrayType::Normal, 0);
+    StrTy = Context.getStringLiteralArrayType(Context.CharTy, Str.size());
   }
 
   return new (Context) ObjCEncodeExpr(StrTy, EncodedTypeInfo, AtLoc, RParenLoc);

lib/Sema/TreeTransform.h

@@ -2713,9 +2713,9 @@ public:
   /// By default, builds a new default-argument expression, which does not
   /// require any semantic analysis. Subclasses may override this routine to
   /// provide different behavior.
-  ExprResult RebuildCXXDefaultArgExpr(SourceLocation Loc,
-                                            ParmVarDecl *Param) {
-    return CXXDefaultArgExpr::Create(getSema().Context, Loc, Param);
+  ExprResult RebuildCXXDefaultArgExpr(SourceLocation Loc, ParmVarDecl *Param) {
+    return CXXDefaultArgExpr::Create(getSema().Context, Loc, Param,
+                                     getSema().CurContext);
   }
 
   /// Build a new C++11 default-initialization expression.
@@ -2725,7 +2725,8 @@ public:
   /// routine to provide different behavior.
   ExprResult RebuildCXXDefaultInitExpr(SourceLocation Loc,
                                        FieldDecl *Field) {
-    return CXXDefaultInitExpr::Create(getSema().Context, Loc, Field);
+    return CXXDefaultInitExpr::Create(getSema().Context, Loc, Field,
+                                      getSema().CurContext);
   }
 
   /// Build a new C++ zero-initialization expression.
@@ -2979,6 +2980,18 @@ public:
                                   RParenLoc, Length, PartialArgs);
   }
 
+  /// Build a new expression representing a call to a source location
+  ///  builtin.
+  ///
+  /// By default, performs semantic analysis to build the new expression.
+  /// Subclasses may override this routine to provide different behavior.
+  ExprResult RebuildSourceLocExpr(SourceLocExpr::IdentKind Kind,
+                                  SourceLocation BuiltinLoc,
+                                  SourceLocation RPLoc,
+                                  DeclContext *ParentContext) {
+    return getSema().BuildSourceLocExpr(Kind, BuiltinLoc, RPLoc, ParentContext);
+  }
+
   /// Build a new Objective-C boxed expression.
   ///
   /// By default, performs semantic analysis to build the new expression.
@@ -10132,6 +10145,19 @@ TreeTransform<Derived>::TransformCXXMemberCallExpr(CXXMemberCallExpr *E) {
   return getDerived().TransformCallExpr(E);
 }
 
+template <typename Derived>
+ExprResult TreeTransform<Derived>::TransformSourceLocExpr(SourceLocExpr *E) {
+  bool NeedRebuildFunc = E->getIdentKind() == SourceLocExpr::Function &&
+                         getSema().CurContext != E->getParentContext();
+
+  if (!getDerived().AlwaysRebuild() && !NeedRebuildFunc)
+    return E;
+
+  return getDerived().RebuildSourceLocExpr(E->getIdentKind(), E->getBeginLoc(),
+                                           E->getEndLoc(),
+                                           getSema().CurContext);
+}
+
 template<typename Derived>
 ExprResult
 TreeTransform<Derived>::TransformCUDAKernelCallExpr(CUDAKernelCallExpr *E) {
@@ -10358,8 +10384,8 @@ TreeTransform<Derived>::TransformCXXDefaultArgExpr(CXXDefaultArgExpr *E) {
   if (!Param)
     return ExprError();
 
-  if (!getDerived().AlwaysRebuild() &&
-      Param == E->getParam())
+  if (!getDerived().AlwaysRebuild() && Param == E->getParam() &&
+      E->getUsedContext() == SemaRef.CurContext)
     return E;
 
   return getDerived().RebuildCXXDefaultArgExpr(E->getUsedLocation(), Param);
@@ -10373,7 +10399,8 @@ TreeTransform<Derived>::TransformCXXDefaultInitExpr(CXXDefaultInitExpr *E) {
   if (!Field)
     return ExprError();
 
-  if (!getDerived().AlwaysRebuild() && Field == E->getField())
+  if (!getDerived().AlwaysRebuild() && Field == E->getField() &&
+      E->getUsedContext() == SemaRef.CurContext)
     return E;
 
   return getDerived().RebuildCXXDefaultInitExpr(E->getExprLoc(), Field);

lib/Serialization/ASTReaderStmt.cpp

@@ -968,6 +968,15 @@ void ASTStmtReader::VisitVAArgExpr(VAArgExpr *E) {
   E->setIsMicrosoftABI(Record.readInt());
 }
 
+void ASTStmtReader::VisitSourceLocExpr(SourceLocExpr *E) {
+  VisitExpr(E);
+  E->ParentContext = ReadDeclAs<DeclContext>();
+  E->BuiltinLoc = ReadSourceLocation();
+  E->RParenLoc = ReadSourceLocation();
+  E->SourceLocExprBits.Kind =
+      static_cast<SourceLocExpr::IdentKind>(Record.readInt());
+}
+
 void ASTStmtReader::VisitAddrLabelExpr(AddrLabelExpr *E) {
   VisitExpr(E);
   E->setAmpAmpLoc(ReadSourceLocation());
@@ -1487,12 +1496,14 @@ void ASTStmtReader::VisitCXXThrowExpr(CXXThrowExpr *E) {
 void ASTStmtReader::VisitCXXDefaultArgExpr(CXXDefaultArgExpr *E) {
   VisitExpr(E);
   E->Param = ReadDeclAs<ParmVarDecl>();
+  E->UsedContext = ReadDeclAs<DeclContext>();
   E->CXXDefaultArgExprBits.Loc = ReadSourceLocation();
 }
 
 void ASTStmtReader::VisitCXXDefaultInitExpr(CXXDefaultInitExpr *E) {
   VisitExpr(E);
   E->Field = ReadDeclAs<FieldDecl>();
+  E->UsedContext = ReadDeclAs<DeclContext>();
   E->CXXDefaultInitExprBits.Loc = ReadSourceLocation();
 }
 
@@ -2651,6 +2662,10 @@ Stmt *ASTReader::ReadStmtFromStream(ModuleFile &F) {
       S = new (Context) VAArgExpr(Empty);
       break;
 
+    case EXPR_SOURCE_LOC:
+      S = new (Context) SourceLocExpr(Empty);
+      break;
+
     case EXPR_ADDR_LABEL:
       S = new (Context) AddrLabelExpr(Empty);
       break;

lib/Serialization/ASTWriterStmt.cpp

@@ -909,6 +909,15 @@ void ASTStmtWriter::VisitVAArgExpr(VAArgExpr *E) {
   Code = serialization::EXPR_VA_ARG;
 }
 
+void ASTStmtWriter::VisitSourceLocExpr(SourceLocExpr *E) {
+  VisitExpr(E);
+  Record.AddDeclRef(cast_or_null<Decl>(E->getParentContext()));
+  Record.AddSourceLocation(E->getBeginLoc());
+  Record.AddSourceLocation(E->getEndLoc());
+  Record.push_back(E->getIdentKind());
+  Code = serialization::EXPR_SOURCE_LOC;
+}
+
 void ASTStmtWriter::VisitAddrLabelExpr(AddrLabelExpr *E) {
   VisitExpr(E);
   Record.AddSourceLocation(E->getAmpAmpLoc());
@@ -1468,6 +1477,7 @@ void ASTStmtWriter::VisitCXXThrowExpr(CXXThrowExpr *E) {
 void ASTStmtWriter::VisitCXXDefaultArgExpr(CXXDefaultArgExpr *E) {
   VisitExpr(E);
   Record.AddDeclRef(E->getParam());
+  Record.AddDeclRef(cast_or_null<Decl>(E->getUsedContext()));
   Record.AddSourceLocation(E->getUsedLocation());
   Code = serialization::EXPR_CXX_DEFAULT_ARG;
 }
@@ -1475,6 +1485,7 @@ void ASTStmtWriter::VisitCXXDefaultArgExpr(CXXDefaultArgExpr *E) {
 void ASTStmtWriter::VisitCXXDefaultInitExpr(CXXDefaultInitExpr *E) {
   VisitExpr(E);
   Record.AddDeclRef(E->getField());
+  Record.AddDeclRef(cast_or_null<Decl>(E->getUsedContext()));
   Record.AddSourceLocation(E->getExprLoc());
   Code = serialization::EXPR_CXX_DEFAULT_INIT;
 }

lib/StaticAnalyzer/Core/ExprEngine.cpp

@@ -1341,6 +1341,7 @@ void ExprEngine::Visit(const Stmt *S, ExplodedNode *Pred,
     case Stmt::NoInitExprClass:
     case Stmt::SizeOfPackExprClass:
     case Stmt::StringLiteralClass:
+    case Stmt::SourceLocExprClass:
     case Stmt::ObjCStringLiteralClass:
     case Stmt::CXXPseudoDestructorExprClass:
     case Stmt::SubstNonTypeTemplateParmExprClass:

test/CodeGenCXX/builtin-source-location.cpp

@@ -0,0 +1,268 @@
+// RUN: %clang_cc1 -std=c++2a -fblocks %s -triple %itanium_abi_triple -emit-llvm -o %t.ll
+
+#line 8 "builtin-source-location.cpp"
+
+struct source_location {
+private:
+  unsigned int __m_line = 0;
+  unsigned int __m_col = 0;
+  const char *__m_file = nullptr;
+  const char *__m_func = nullptr;
+
+public:
+  constexpr void set(unsigned l, unsigned c, const char *f, const char *func) {
+    __m_line = l;
+    __m_col = c;
+    __m_file = f;
+    __m_func = func;
+  }
+  static constexpr source_location current(
+      unsigned int __line = __builtin_LINE(),
+      unsigned int __col = __builtin_COLUMN(),
+      const char *__file = __builtin_FILE(),
+      const char *__func = __builtin_FUNCTION()) noexcept {
+    source_location __loc;
+    __loc.set(__line, __col, __file, __func);
+    return __loc;
+  }
+  static source_location bad_current(
+      unsigned int __line = __builtin_LINE(),
+      unsigned int __col = __builtin_COLUMN(),
+      const char *__file = __builtin_FILE(),
+      const char *__func = __builtin_FUNCTION()) noexcept {
+    source_location __loc;
+    __loc.set(__line, __col, __file, __func);
+    return __loc;
+  }
+  constexpr source_location() = default;
+  constexpr source_location(source_location const &) = default;
+  constexpr unsigned int line() const noexcept { return __m_line; }
+  constexpr unsigned int column() const noexcept { return __m_col; }
+  constexpr const char *file() const noexcept { return __m_file; }
+  constexpr const char *function() const noexcept { return __m_func; }
+};
+
+using SL = source_location;
+
+extern "C" int sink(...);
+
+
+// RUN: FileCheck --input-file %t.ll %s --check-prefix=CHECK-GLOBAL-ONE
+//
+// CHECK-GLOBAL-ONE-DAG: @[[FILE:.*]] = {{.*}}c"test_const_init.cpp\00"
+// CHECK-GLOBAL-ONE-DAG: @[[FUNC:.*]] = private unnamed_addr constant [1 x i8] zeroinitializer, align 1
+//
+// CHECK-GLOBAL-ONE: @const_init_global = global %struct.source_location { i32 1000, i32 {{[0-9]+}}, {{[^@]*}}@[[FILE]], {{[^@]*}}@[[FUNC]]
+#line 1000 "test_const_init.cpp"
+SL const_init_global = SL::current();
+
+// RUN: FileCheck --input-file %t.ll %s --check-prefix=CHECK-GLOBAL-TWO
+//
+// CHECK-GLOBAL-TWO-DAG: @runtime_init_global = global %struct.source_location zeroinitializer, align 8
+//
+// CHECK-GLOBAL-TWO-DAG: @[[FILE:.*]] = {{.*}}c"test_runtime_init.cpp\00"
+// CHECK-GLOBAL-TWO-DAG: @[[FUNC:.*]] = private unnamed_addr constant [1 x i8] zeroinitializer, align 1
+//
+// CHECK-GLOBAL-TWO: define internal void @__cxx_global_var_init()
+// CHECK-GLOBAL-TWO-NOT: ret
+// CHECK-GLOBAL-TWO: call void @_ZN15source_location11bad_currentEjjPKcS1_(%struct.source_location* sret @runtime_init_global,
+// CHECK-GLOBAL-TWO-SAME: i32 1100, i32 {{[0-9]+}}, {{[^@]*}}@[[FILE]], {{[^@]*}}@[[FUNC]],
+#line 1100 "test_runtime_init.cpp"
+SL runtime_init_global = SL::bad_current();
+
+#line 2000 "test_function.cpp"
+extern "C" void test_function() {
+// RUN: FileCheck --input-file %t.ll %s --check-prefix=CHECK-LOCAL-ONE
+//
+// CHECK-LOCAL-ONE-DAG: @[[FILE:.*]] = {{.*}}c"test_current.cpp\00"
+// CHECK-LOCAL-ONE-DAG: @[[FUNC:.*]] = {{.*}}c"test_function\00"
+//
+// CHECK-LOCAL-ONE:  call void @_ZN15source_location7currentEjjPKcS1_(%struct.source_location* sret %local,
+// CHECK-LOCAL-ONE-SAME: i32 2100, i32 {{[0-9]+}},
+// CHECK-LOCAL-ONE-SAME: {{[^@]*}}@[[FILE]], {{[^@]*}}@[[FUNC]],
+#line 2100 "test_current.cpp"
+  SL local = SL::current();
+}
+
+#line 3000 "TestInitClass.cpp"
+struct TestInit {
+  SL info = SL::current();
+  SL arg_info;
+
+#line 3100 "TestInitCtor.cpp"
+  TestInit(SL arg_info = SL::current()) : arg_info(arg_info) {}
+};
+
+// RUN: FileCheck --input-file %t.ll %s --check-prefix=CHECK-CTOR-GLOBAL
+//
+// CHECK-CTOR-GLOBAL-DAG: @GlobalInitVal = global %struct.TestInit zeroinitializer, align 8
+// CHECK-CTOR-GLOBAL-DAG: @[[FILE:.*]] = {{.*}}c"GlobalInitVal.cpp\00"
+// CHECK-CTOR-GLOBAL-DAG: @[[FUNC:.*]] = private unnamed_addr constant [1 x i8] zeroinitializer, align 1
+//
+// CHECK-CTOR-GLOBAL: define internal void @__cxx_global_var_init.{{[0-9]+}}()
+// CHECK-CTOR-GLOBAL-NOT: ret
+//
+// CHECK-CTOR-GLOBAL: call void @_ZN15source_location7currentEjjPKcS1_(%struct.source_location* sret %[[TMP_ONE:[^,]*]],
+// CHECK-CTOR-GLOBAL-SAME: i32 3400, i32 {{[0-9]+}}, {{[^@]*}}@[[FILE]], {{[^@]*}}@[[FUNC]],
+// CHECK-CTOR-GLOBAL-NEXT: call void @_ZN8TestInitC1E15source_location(%struct.TestInit* @GlobalInitVal, %struct.source_location* {{[^%]*}}%[[TMP_ONE]])
+#line 3400 "GlobalInitVal.cpp"
+TestInit GlobalInitVal;
+
+extern "C" void test_init_function() {
+// RUN: FileCheck --input-file %t.ll %s --check-prefix=CHECK-CTOR-LOCAL
+//
+// CHECK-CTOR-LOCAL-DAG: @[[FILE:.*]] = {{.*}}c"LocalInitVal.cpp\00"
+// CHECK-CTOR-LOCAL-DAG: @[[FUNC:.*]] = {{.*}}c"test_init_function\00"
+//
+// CHECK-CTOR-LOCAL: define void @test_init_function()
+// CHECK-CTOR-LOCAL-NOT: ret
+//
+// CHECK-CTOR-LOCAL: call void @_ZN15source_location7currentEjjPKcS1_(%struct.source_location* sret %[[TMP:[^,]*]],
+// CHECK-CTOR-LOCAL-SAME: i32 3500, i32 {{[0-9]+}}, {{[^@]*}}@[[FILE]], {{[^@]*}}@[[FUNC]],
+// CHECK-CTOR-LOCAL-NEXT: call void @_ZN8TestInitC1E15source_location(%struct.TestInit* %init_local, %struct.source_location* {{[^%]*}}%[[TMP]])
+#line 3500 "LocalInitVal.cpp"
+  TestInit init_local;
+  sink(init_local);
+}
+
+#line 4000 "ConstexprClass.cpp"
+struct TestInitConstexpr {
+  SL info = SL::current();
+  SL arg_info;
+#line 4200 "ConstexprCtor.cpp"
+  constexpr TestInitConstexpr(SL arg_info = SL::current()) : arg_info(arg_info) {}
+};
+
+// RUN: FileCheck --input-file %t.ll %s --check-prefix=CHECK-CONSTEXPR-T2
+//
+// CHECK-CONSTEXPR-T2-DAG: @[[FILE_INIT:.*]] = {{.*}}c"ConstexprCtor.cpp\00"
+// CHECK-CONSTEXPR-T2-DAG: @[[FUNC_INIT:.*]] = {{.*}}c"TestInitConstexpr\00"
+// CHECK-CONSTEXPR-T2-DAG: @[[FILE_ARG:.*]] = {{.*}}c"ConstexprGlobal.cpp\00"
+// CHECK-CONSTEXPR-T2-DAG: @[[EMPTY:.*]] = private unnamed_addr constant [1 x i8] zeroinitializer, align 1
+//
+// CHECK-CONSTEXPR-T2: @ConstexprGlobal = global %struct.TestInitConstexpr {
+// CHECK-CONSTEXPR-T2-SAME: %struct.source_location { i32 4200, i32 {{[0-9]+}}, {{[^@]*}}@[[FILE_INIT]], {{[^@]*}}@[[FUNC_INIT]],
+// CHECK-CONSTEXPR-T2-SAME: {{[^%]*}}%struct.source_location { i32 4400, i32 {{[0-9]+}},  {{[^@]*}}@[[FILE_ARG]], {{[^@]*}}@[[EMPTY]]
+#line 4400 "ConstexprGlobal.cpp"
+TestInitConstexpr ConstexprGlobal;
+
+extern "C" void test_init_function_constexpr() {
+// RUN: FileCheck --input-file %t.ll %s --check-prefix=CHECK-CONSTEXPR-LOCAL
+//
+// CHECK-CONSTEXPR-LOCAL-DAG: @[[FUNC:.*]] = {{.*}}c"test_init_function_constexpr\00"
+// CHECK-CONSTEXPR-LOCAL-DAG: @[[FILE:.*]] = {{.*}}c"ConstexprLocal.cpp\00"
+//
+// CHECK-CONSTEXPR-LOCAL: define void @test_init_function_constexpr()
+// CHECK-CONSTEXPR-LOCAL: call void @_ZN15source_location7currentEjjPKcS1_(%struct.source_location* sret %[[TMP:[^,]*]],
+// CHECK-CONSTEXPR-LOCAL-SAME: i32 4600, i32 {{[0-9]+}}, {{[^@]*}}@[[FILE]], {{[^@]*}}@[[FUNC]]
+// CHECK-CONSTEXPR-LOCAL: call void @_ZN17TestInitConstexprC1E15source_location(%struct.TestInitConstexpr* %local_val, {{.*}}%[[TMP]])
+#line 4600 "ConstexprLocal.cpp"
+  TestInitConstexpr local_val;
+}
+
+#line 5000 "TestInitAgg.cpp"
+struct TestInitAgg {
+#line 5100 "i1.cpp"
+  SL i1;
+#line 5200 "i2.cpp"
+  SL i2 = SL::current();
+#line 5300 "TestInitAggEnd.cpp"
+};
+
+// RUN: FileCheck --input-file %t.ll %s --check-prefix=CHECK-AGG-DEFAULT
+//
+// CHECK-AGG-DEFAULT-DAG: @[[FILE:.*]] = {{.*}}c"TestInitAgg.cpp\00"
+// CHECK-AGG-DEFAULT-DAG: @[[FUNC:.*]] = {{.*}}c"TestInitAgg\00"
+//
+// CHECK-AGG-DEFAULT: @GlobalAggDefault = global %struct.TestInitAgg {
+// CHECK-AGG-DEFAULT-SAME: %struct.source_location zeroinitializer,
+// CHECK-AGG-DEFAULT-SAME: %struct.source_location { i32 5000, i32 {{[0-9]+}}, {{[^@]*}}@[[FILE]], {{[^@]*}}@[[FUNC]]
+#line 5400 "GlobalAggDefault.cpp"
+TestInitAgg GlobalAggDefault;
+
+#line 5500 "test_agg_init_test.cpp"
+extern "C" void test_agg_init() {
+// RUN: FileCheck --input-file %t.ll %s --check-prefix=CHECK-AGG-BRACE
+//
+// CHECK-AGG-BRACE-DAG: @[[FILE:.*]] = {{.*}}c"BraceInitEnd.cpp\00"
+// CHECK-AGG-BRACE-DAG: @[[FUNC:.*]] = {{.*}}c"test_agg_init\00"
+//
+// CHECK-AGG-BRACE: define void @test_agg_init()
+// CHECK-AGG-BRACE: %[[I2:.*]] = getelementptr inbounds %struct.TestInitAgg, %struct.TestInitAgg* %local_brace_init, i32 0, i32 1
+// CHECK-AGG-BRACE-NEXT: call void @_ZN15source_location7currentEjjPKcS1_(%struct.source_location* sret %[[I2]],
+// CHECK-AGG-BRACE-SAME: i32 5700, i32 {{[0-9]+}}, {{[^@]*}}@[[FILE]], {{[^@]*}}@[[FUNC]]
+#line 5600 "BraceInitStart.cpp"
+  TestInitAgg local_brace_init{
+#line 5700 "BraceInitEnd.cpp"
+  };
+
+// RUN: FileCheck --input-file %t.ll %s --check-prefix=CHECK-AGG-EQUAL
+//
+// CHECK-AGG-EQUAL-DAG: @[[FILE:.*]] = {{.*}}c"EqualInitEnd.cpp\00"
+// CHECK-AGG-EQUAL-DAG: @[[FUNC:.*]] = {{.*}}c"test_agg_init\00"
+//
+// CHECK-AGG-EQUAL: define void @test_agg_init()
+// CHECK-AGG-EQUAL: %[[I2:.*]] = getelementptr inbounds %struct.TestInitAgg, %struct.TestInitAgg* %local_equal_init, i32 0, i32 1
+// CHECK-AGG-EQUAL-NEXT: call void @_ZN15source_location7currentEjjPKcS1_(%struct.source_location* sret %[[I2]],
+// CHECK-AGG-EQUAL-SAME: i32 5900, i32 {{[0-9]+}}, {{[^@]*}}@[[FILE]], {{[^@]*}}@[[FUNC]]
+#line 5800 "EqualInitStart.cpp"
+  TestInitAgg local_equal_init =
+      {
+#line 5900 "EqualInitEnd.cpp"
+      };
+
+// RUN: FileCheck --input-file %t.ll %s --check-prefix=CHECK-AGG-LIST
+//
+// CHECK-AGG-LIST-DAG: @[[FILE_DEFAULT:.*]] = {{.*}}c"InitListEnd.cpp\00"
+// CHECK-AGG-LIST-DAG: @[[FILE_ELEM:.*]] = {{.*}}c"ListElem.cpp\00"
+// CHECK-AGG-LIST-DAG: @[[FUNC:.*]] = {{.*}}c"test_agg_init\00"
+//
+// CHECK-AGG-LIST: define void @test_agg_init()
+//
+// CHECK-AGG-LIST: %[[I1:.*]] =  getelementptr inbounds %struct.TestInitAgg, %struct.TestInitAgg* %local_list_init, i32 0, i32 0
+// CHECK-AGG-LIST-NEXT: call void @_ZN15source_location7currentEjjPKcS1_(%struct.source_location* sret %[[I1]],
+// CHECK-AGG-LIST-SAME: i32 6100, i32 {{[0-9]+}}, {{[^@]*}}@[[FILE_ELEM]], {{[^@]*}}@[[FUNC]]
+//
+// CHECK-AGG-LIST: %[[I2:.*]] = getelementptr inbounds %struct.TestInitAgg, %struct.TestInitAgg* %local_list_init, i32 0, i32 1
+// CHECK-AGG-LIST-NEXT: call void @_ZN15source_location7currentEjjPKcS1_(%struct.source_location* sret %[[I2]],
+// CHECK-AGG-LIST-SAME: i32 6200, i32 {{[0-9]+}}, {{[^@]*}}@[[FILE_DEFAULT]], {{[^@]*}}@[[FUNC]]
+#line 6000 "InitListStart.cpp"
+  TestInitAgg local_list_init =
+      {
+#line 6100 "ListElem.cpp"
+          {SL::current()}
+#line 6200 "InitListEnd.cpp"
+      };
+}
+
+#line 7000 "TestTemplate.cpp"
+template <class Tp, int>
+struct TestTemplate {
+  Tp info = Tp::current();
+  Tp arg_info;
+#line 7100 "TestTemplateCtor.cpp"
+  constexpr TestTemplate(Tp arg_info = Tp::current()) : arg_info(arg_info) {}
+};
+
+#line 7200 "test_template.cpp"
+template <class T, int V>
+void test_template() {
+
+// RUN: FileCheck --input-file %t.ll %s --check-prefix=CHECK-TEMPL -DINT_ID=0
+// RUN: FileCheck --input-file %t.ll %s --check-prefix=CHECK-TEMPL -DINT_ID=1
+//
+// CHECK-TEMPL-DAG: @[[FILE:.*]] = {{.*}}c"local_templ.cpp\00"
+// CHECK-TEMPL-DAG: @[[FUNC:.*]] = {{.*}}c"test_template\00"
+//
+// CHECK-TEMPL: define weak_odr void @_Z13test_templateI15source_locationLi[[INT_ID]]EEvv()
+// CHECK-TEMPL-NEXT: entry:
+// CHECK-TEMPL-NOT: ret
+//
+// CHECK-TEMPL:  call void @_ZN15source_location7currentEjjPKcS1_(%struct.source_location* sret %[[TMP:[^,]*]],
+// CHECK-TEMPL-SAME: i32 7300, i32 {{[0-9]+}}, {{[^@]*}}@[[FILE]], {{[^@]*}}@[[FUNC]]
+#line 7300 "local_templ.cpp"
+  TestTemplate<T, V> local_templ;
+}
+#line 7400 "EndTestTemplate.cpp"
+template void test_template<SL, 0>();
+template void test_template<SL, 1>();

test/CodeGenCXX/builtin_FUNCTION.cpp

@@ -0,0 +1,41 @@
+// RUN: %clang_cc1 -std=c++2a -fblocks %s -triple %itanium_abi_triple -emit-llvm -o %t.ll
+// RUN: FileCheck --input-file %t.ll %s
+
+namespace test_func {
+
+constexpr const char *test_default_arg(const char *f = __builtin_FUNCTION()) {
+  return f;
+}
+// CHECK: @[[EMPTY_STR:.+]] = private unnamed_addr constant [1 x i8] zeroinitializer, align 1
+
+// CHECK: @_ZN9test_func6globalE = global i8* getelementptr inbounds ([1 x i8], [1 x i8]* @[[EMPTY_STR]], i32 0, i32 0), align 8
+const char *global = test_default_arg();
+
+// CHECK: @_ZN9test_func10global_twoE = global i8* getelementptr inbounds ([1 x i8], [1 x i8]* @[[EMPTY_STR]], i32 0, i32 0), align 8
+const char *global_two = __builtin_FUNCTION();
+
+const char * const global_three = test_default_arg();
+
+// CHECK: @[[STR_ONE:.+]] = private unnamed_addr constant [14 x i8] c"test_func_one\00", align 1
+// CHECK: @[[STR_TWO:.+]] = private unnamed_addr constant [14 x i8] c"test_func_two\00", align 1
+// CHECK: @[[STR_THREE:.+]] = private unnamed_addr constant [20 x i8] c"do_default_arg_test\00", align 1
+
+// CHECK: define i8* @_ZN9test_func13test_func_oneEv()
+// CHECK: ret i8* getelementptr inbounds ([14 x i8], [14 x i8]* @[[STR_ONE]], i32 0, i32 0)
+const char *test_func_one() {
+  return __builtin_FUNCTION();
+}
+
+// CHECK: define i8* @_ZN9test_func13test_func_twoEv()
+// CHECK: ret i8* getelementptr inbounds ([14 x i8], [14 x i8]* @[[STR_TWO]], i32 0, i32 0)
+const char *test_func_two() {
+  return __builtin_FUNCTION();
+}
+
+// CHECK: define void @_ZN9test_func19do_default_arg_testEv()
+// CHECK: %call = call i8* @_ZN9test_func16test_default_argEPKc(i8* getelementptr inbounds ([20 x i8], [20 x i8]* @[[STR_THREE]], i32 0, i32 0))
+void do_default_arg_test() {
+  test_default_arg();
+}
+
+} // namespace test_func

test/CodeGenCXX/builtin_LINE.cpp

@@ -0,0 +1,95 @@
+// RUN: %clang_cc1 -std=c++1z -fblocks %s -triple %itanium_abi_triple -emit-llvm -o - | FileCheck %s
+
+extern "C" int sink;
+extern "C" const volatile void* volatile ptr_sink = nullptr;
+
+struct Tag1 {};
+struct Tag2 {};
+struct Tag3 {};
+struct Tag4 {};
+
+constexpr int get_line_constexpr(int l = __builtin_LINE()) {
+  return l;
+}
+
+int get_line_nonconstexpr(int l = __builtin_LINE()) {
+  return l;
+}
+
+
+int get_line(int l = __builtin_LINE()) {
+  return l;
+}
+
+int get_line2(int l = get_line()) { return l; }
+
+
+// CHECK: @global_one = global i32 [[@LINE+1]], align 4
+int global_one = __builtin_LINE();
+// CHECK-NEXT: @global_two = global i32 [[@LINE+1]], align 4
+int global_two = get_line_constexpr();
+// CHECK: @_ZL12global_three = internal constant i32 [[@LINE+1]], align 4
+const int global_three(get_line_constexpr());
+
+// CHECK-LABEL: define internal void @__cxx_global_var_init
+// CHECK: %call = call i32 @_Z21get_line_nonconstexpri(i32 [[@LINE+2]])
+// CHECK-NEXT: store i32 %call, i32* @global_four, align 4
+int global_four = get_line_nonconstexpr();
+
+struct InClassInit {
+  int Init = __builtin_LINE();
+  int Init2 = get_line2();
+  InClassInit();
+  constexpr InClassInit(Tag1, int l = __builtin_LINE()) : Init(l), Init2(l) {}
+  constexpr InClassInit(Tag2) : Init(__builtin_LINE()), Init2(__builtin_LINE()) {}
+  InClassInit(Tag3, int l = __builtin_LINE());
+  InClassInit(Tag4, int l = get_line2());
+
+  static void test_class();
+};
+// CHECK-LABEL: define void @_ZN11InClassInit10test_classEv()
+void InClassInit::test_class() {
+  // CHECK: call void @_ZN11InClassInitC1Ev(%struct.InClassInit* %test_one)
+  InClassInit test_one;
+  // CHECK-NEXT: call void @_ZN11InClassInitC1E4Tag1i(%struct.InClassInit* %test_two, i32 [[@LINE+1]])
+  InClassInit test_two{Tag1{}};
+  // CHECK-NEXT: call void @_ZN11InClassInitC1E4Tag2(%struct.InClassInit* %test_three)
+  InClassInit test_three{Tag2{}};
+  // CHECK-NEXT: call void @_ZN11InClassInitC1E4Tag3i(%struct.InClassInit* %test_four, i32 [[@LINE+1]])
+  InClassInit test_four(Tag3{});
+  // CHECK-NEXT: %[[CALL:.+]] = call i32 @_Z8get_linei(i32 [[@LINE+3]])
+  // CHECK-NEXT: %[[CALL2:.+]] = call i32 @_Z9get_line2i(i32 %[[CALL]])
+  // CHECK-NEXT: call void @_ZN11InClassInitC1E4Tag4i(%struct.InClassInit* %test_five, i32 %[[CALL2]])
+  InClassInit test_five(Tag4{});
+
+}
+// CHECK-LABEL: define void @_ZN11InClassInitC2Ev
+// CHECK: store i32 [[@LINE+4]], i32* %Init, align 4
+// CHECK: %call = call i32 @_Z8get_linei(i32 [[@LINE+3]])
+// CHECK-NEXT: %call2 = call i32 @_Z9get_line2i(i32 %call)
+// CHECK-NEXT: store i32 %call2, i32* %Init2, align 4
+InClassInit::InClassInit() = default;
+
+InClassInit::InClassInit(Tag3, int l) : Init(l) {}
+
+// CHECK-LABEL: define void @_ZN11InClassInitC2E4Tag4i(%struct.InClassInit* %this, i32 %arg)
+// CHECK:  %[[TEMP:.+]] = load i32, i32* %arg.addr, align 4
+// CHECK-NEXT: store i32 %[[TEMP]], i32* %Init, align 4
+// CHECK: %[[CALL:.+]] = call i32 @_Z8get_linei(i32 [[@LINE+3]])
+// CHECK-NEXT: %[[CALL2:.+]] = call i32 @_Z9get_line2i(i32 %[[CALL]])
+// CHECK-NEXT: store i32 %[[CALL2]], i32* %Init2, align 4
+InClassInit::InClassInit(Tag4, int arg) : Init(arg) {}
+
+// CHECK-LABEL: define void @_Z13get_line_testv()
+void get_line_test() {
+  // CHECK: %[[CALL:.+]] = call i32 @_Z8get_linei(i32 [[@LINE+2]])
+  // CHECK-NEXT: store i32 %[[CALL]], i32* @sink, align 4
+  sink = get_line();
+  // CHECK-NEXT:  store i32 [[@LINE+1]], i32* @sink, align 4
+  sink = __builtin_LINE();
+  ptr_sink = &global_three;
+}
+
+void foo() {
+  const int N[] = {__builtin_LINE(), get_line_constexpr()};
+}

test/CodeGenCXX/debug-info-line.cpp

@@ -293,6 +293,13 @@ void f24() {
   f24_a();
 }
 
+// CHECK-LABEL: define
+void f25_a(int x = __builtin_LINE()) {}
+void f25() {
+  // CHECK: call void @_Z5f25_ai(i32 2700)
+#line 2700
+  f25_a();
+}
 // CHECK: [[DBG_F1]] = !DILocation(line: 100,
 // CHECK: [[DBG_FOO_VALUE]] = !DILocation(line: 200,
 // CHECK: [[DBG_FOO_REF]] = !DILocation(line: 202,

test/Parser/builtin_source_location.c

@@ -0,0 +1,19 @@
+// RUN: %clang_cc1 -fsyntax-only -verify %s
+
+int main() {
+  int line = __builtin_LINE();
+  __builtin_LINE(42); // expected-error {{expected ')'}}
+  __builtin_LINE(double); // expected-error {{expected ')'}}
+
+  int column = __builtin_COLUMN();
+  __builtin_COLUMN(42); // expected-error {{expected ')'}}
+  __builtin_COLUMN(double); // expected-error {{expected ')'}}
+
+  const char *func = __builtin_FUNCTION();
+  __builtin_FUNCTION(42); // expected-error {{expected ')'}}
+  __builtin_FUNCTION(double); // expected-error {{expected ')'}}
+
+  const char *file = __builtin_FILE();
+  __builtin_FILE(42); // expected-error {{expected ')'}}
+  __builtin_FILE(double); // expected-error {{expected ')'}}
+}

test/Sema/source_location.c

@@ -0,0 +1,32 @@
+// RUN: %clang_cc1 -std=c90 -fconst-strings -DCONST_STRINGS -verify %s
+// RUN: %clang_cc1 -std=c90 -verify %s
+
+// expected-no-diagnostics
+
+#define IsEqual(L, R) (__builtin_strcmp(L, R) == 0)
+
+const char *const FILE = __builtin_FILE();
+const char *const FUNC = __builtin_FUNCTION();
+const unsigned LINE = __builtin_LINE();
+const unsigned COL = __builtin_COLUMN();
+
+#ifndef CONST_STRINGS
+char *const NCFILE = __builtin_FILE();
+char *const NCFUNC = __builtin_FUNCTION();
+#endif
+
+#ifdef CONST_STRINGS
+_Static_assert(IsEqual(__builtin_FILE(), __FILE__), "");
+_Static_assert(__builtin_LINE() == __LINE__, "");
+_Static_assert(IsEqual("", __builtin_FUNCTION()), "");
+
+#line 42 "my_file.c"
+_Static_assert(__builtin_LINE() == 42, "");
+_Static_assert(IsEqual(__builtin_FILE(), "my_file.c"), "");
+
+_Static_assert(__builtin_COLUMN() == __builtin_strlen("_Static_assert(_"), "");
+
+void foo() {
+  _Static_assert(IsEqual(__builtin_FUNCTION(), "foo"), "");
+}
+#endif // CONST_STRINGS

test/SemaCXX/Inputs/source-location-file.h

@@ -0,0 +1,44 @@
+
+// NOTE: source_location.cpp must include this file after defining
+// std::source_location.
+namespace source_location_file {
+
+constexpr const char *FILE = __FILE__;
+
+constexpr SL global_info = SL::current();
+
+constexpr SL test_function(SL v = SL::current()) {
+  return v;
+}
+
+constexpr SL test_function_indirect() {
+  return test_function();
+}
+
+template <class T, class U = SL>
+constexpr U test_function_template(T, U u = U::current()) {
+  return u;
+}
+
+template <class T, class U = SL>
+constexpr U test_function_template_indirect(T t) {
+  return test_function_template(t);
+}
+
+struct TestClass {
+  SL info = SL::current();
+  SL ctor_info;
+  TestClass() = default;
+  constexpr TestClass(int, SL cinfo = SL::current()) : ctor_info(cinfo) {}
+  template <class T, class U = SL>
+  constexpr TestClass(int, T, U u = U::current()) : ctor_info(u) {}
+};
+
+template <class T = SL>
+struct AggrClass {
+  int x;
+  T info;
+  T init_info = T::current();
+};
+
+} // namespace source_location_file

test/SemaCXX/source_location.cpp

@@ -0,0 +1,590 @@
+// RUN: %clang_cc1 -std=c++1z -fcxx-exceptions -fexceptions -verify %s
+// expected-no-diagnostics
+
+#define assert(...) ((__VA_ARGS__) ? ((void)0) : throw 42)
+#define CURRENT_FROM_MACRO() SL::current()
+#define FORWARD(...) __VA_ARGS__
+
+template <unsigned>
+struct Printer;
+
+namespace std {
+namespace experimental {
+struct source_location {
+private:
+  unsigned int __m_line = 0;
+  unsigned int __m_col = 0;
+  const char *__m_file = nullptr;
+  const char *__m_func = nullptr;
+public:
+  static constexpr source_location current(
+      const char *__file = __builtin_FILE(),
+      const char *__func = __builtin_FUNCTION(),
+      unsigned int __line = __builtin_LINE(),
+      unsigned int __col = __builtin_COLUMN()) noexcept {
+    source_location __loc;
+    __loc.__m_line = __line;
+    __loc.__m_col = __col;
+    __loc.__m_file = __file;
+    __loc.__m_func = __func;
+    return __loc;
+  }
+  constexpr source_location() = default;
+  constexpr source_location(source_location const &) = default;
+  constexpr unsigned int line() const noexcept { return __m_line; }
+  constexpr unsigned int column() const noexcept { return __m_col; }
+  constexpr const char *file() const noexcept { return __m_file; }
+  constexpr const char *function() const noexcept { return __m_func; }
+};
+} // namespace experimental
+} // namespace std
+
+using SL = std::experimental::source_location;
+
+#include "Inputs/source-location-file.h"
+namespace SLF = source_location_file;
+
+constexpr bool is_equal(const char *LHS, const char *RHS) {
+  while (*LHS != 0 && *RHS != 0) {
+    if (*LHS != *RHS)
+      return false;
+    ++LHS;
+    ++RHS;
+  }
+  return *LHS == 0 && *RHS == 0;
+}
+
+template <class T>
+constexpr T identity(T t) {
+  return t;
+}
+
+template <class T, class U>
+struct Pair {
+  T first;
+  U second;
+};
+
+template <class T, class U>
+constexpr bool is_same = false;
+template <class T>
+constexpr bool is_same<T, T> = true;
+
+// test types
+static_assert(is_same<decltype(__builtin_LINE()), unsigned>);
+static_assert(is_same<decltype(__builtin_COLUMN()), unsigned>);
+static_assert(is_same<decltype(__builtin_FILE()), const char *>);
+static_assert(is_same<decltype(__builtin_FUNCTION()), const char *>);
+
+// test noexcept
+static_assert(noexcept(__builtin_LINE()));
+static_assert(noexcept(__builtin_COLUMN()));
+static_assert(noexcept(__builtin_FILE()));
+static_assert(noexcept(__builtin_FUNCTION()));
+
+//===----------------------------------------------------------------------===//
+//                            __builtin_LINE()
+//===----------------------------------------------------------------------===//
+
+namespace test_line {
+static_assert(SL::current().line() == __LINE__);
+static_assert(SL::current().line() == CURRENT_FROM_MACRO().line());
+
+static constexpr SL GlobalS = SL::current();
+
+static_assert(GlobalS.line() == __LINE__ - 2);
+
+// clang-format off
+constexpr bool test_line_fn() {
+  constexpr SL S = SL::current();
+  static_assert(S.line() == (__LINE__ - 1), "");
+  // The start of the call expression to `current()` begins at the token `SL`
+  constexpr int ExpectLine = __LINE__ + 3;
+  constexpr SL S2
+  =
+  SL // Call expression starts here
+  ::
+  current
+  (
+
+  )
+  ;
+  static_assert(S2.line() == ExpectLine, "");
+
+  static_assert(
+          FORWARD(
+             __builtin_LINE
+            (
+            )
+          )
+    == __LINE__ - 1, "");
+  static_assert(\
+\
+  __builtin_LINE()\
+\
+  == __LINE__ - 2, "");
+  static_assert(\
+          _\
+_builtin_LINE()
+          == __LINE__ - 2, "");
+
+  return true;
+}
+// clang-format on
+static_assert(test_line_fn());
+
+static_assert(__builtin_LINE() == __LINE__, "");
+
+constexpr int baz() { return 101; }
+
+constexpr int test_line_fn_simple(int z = baz(), int x = __builtin_LINE()) {
+  return x;
+}
+void bar() {
+  static_assert(test_line_fn_simple() == __LINE__, "");
+  static_assert(test_line_fn_simple() == __LINE__, "");
+}
+
+struct CallExpr {
+  constexpr int operator()(int x = __builtin_LINE()) const { return x; }
+};
+constexpr CallExpr get_call() { return CallExpr{}; }
+static_assert(get_call()() == __LINE__, "");
+
+template <class T>
+constexpr bool test_line_fn_template(T Expect, int L = __builtin_LINE()) {
+  return Expect == L;
+}
+static_assert(test_line_fn_template(__LINE__));
+
+struct InMemInit {
+  constexpr bool check(int expect) const {
+    return info.line() == expect;
+  }
+  SL info = SL::current();
+  InMemInit() = default;
+  constexpr InMemInit(int) {}
+};
+static_assert(InMemInit{}.check(__LINE__ - 3), "");
+static_assert(InMemInit{42}.check(__LINE__ - 3), "");
+
+template <class T, class U = SL>
+struct InMemInitTemplate {
+  constexpr bool check(int expect) const {
+    return info.line() == expect;
+  }
+  U info = U::current();
+  InMemInitTemplate() = default;
+  constexpr InMemInitTemplate(T) {}
+  constexpr InMemInitTemplate(T, T) : info(U::current()) {}
+  template <class V = U> constexpr InMemInitTemplate(T, T, T, V info = U::current())
+      : info(info) {}
+};
+void test_mem_init_template() {
+  constexpr int line_offset = 8;
+  static_assert(InMemInitTemplate<int>{}.check(__LINE__ - line_offset), "");
+  static_assert(InMemInitTemplate<unsigned>{42}.check(__LINE__ - line_offset), "");
+  static_assert(InMemInitTemplate<unsigned>{42, 42}.check(__LINE__ - line_offset), "");
+  static_assert(InMemInitTemplate<unsigned>{42, 42, 42}.check(__LINE__), "");
+}
+
+struct AggInit {
+  int x;
+  int y = __builtin_LINE();
+  constexpr bool check(int expect) const {
+    return y == expect;
+  }
+};
+constexpr AggInit AI{42};
+static_assert(AI.check(__LINE__ - 1), "");
+
+template <class T, class U = SL>
+struct AggInitTemplate {
+  constexpr bool check(int expect) const {
+    return expect == info.line();
+  }
+  T x;
+  U info = U::current();
+};
+
+template <class T, class U = SL>
+constexpr U test_fn_template(T, U u = U::current()) {
+  return u;
+}
+void fn_template_tests() {
+  static_assert(test_fn_template(42).line() == __LINE__, "");
+}
+
+struct TestMethodTemplate {
+  template <class T, class U = SL, class U2 = SL>
+  constexpr U get(T, U u = U::current(), U2 u2 = identity(U2::current())) const {
+    assert(u.line() == u2.line());
+    return u;
+  }
+};
+void method_template_tests() {
+  static_assert(TestMethodTemplate{}.get(42).line() == __LINE__, "");
+}
+
+struct InStaticInit {
+  static constexpr int LINE = __LINE__;
+  static constexpr const int x1 = __builtin_LINE();
+  static constexpr const int x2 = identity(__builtin_LINE());
+  static const int x3;
+  const int x4 = __builtin_LINE();
+  int x5 = __builtin_LINE();
+};
+const int InStaticInit::x3 = __builtin_LINE();
+static_assert(InStaticInit::x1 == InStaticInit::LINE + 1, "");
+static_assert(InStaticInit::x2 == InStaticInit::LINE + 2, "");
+
+template <class T, int N = __builtin_LINE(), int Expect = -1>
+constexpr void check_fn_template_param(T) {
+  constexpr int RealExpect = Expect == -1 ? __LINE__ - 2 : Expect;
+  static_assert(N == RealExpect);
+}
+template void check_fn_template_param(int);
+template void check_fn_template_param<long, 42, 42>(long);
+
+#line 100
+struct AggBase {
+#line 200
+  int x = __builtin_LINE();
+  int y = __builtin_LINE();
+  int z = __builtin_LINE();
+};
+#line 300
+struct AggDer : AggBase {
+};
+#line 400
+static_assert(AggDer{}.x == 400, "");
+
+struct ClassBase {
+#line 400
+  int x = __builtin_LINE();
+  int y = 0;
+  int z = 0;
+#line 500
+  ClassBase() = default;
+  constexpr ClassBase(int yy, int zz = __builtin_LINE())
+      : y(yy), z(zz) {}
+};
+struct ClassDer : ClassBase {
+#line 600
+  ClassDer() = default;
+  constexpr ClassDer(int yy) : ClassBase(yy) {}
+  constexpr ClassDer(int yy, int zz) : ClassBase(yy, zz) {}
+};
+#line 700
+static_assert(ClassDer{}.x == 500, "");
+static_assert(ClassDer{42}.x == 501, "");
+static_assert(ClassDer{42}.z == 601, "");
+static_assert(ClassDer{42, 42}.x == 501, "");
+
+struct ClassAggDer : AggBase {
+#line 800
+  ClassAggDer() = default;
+  constexpr ClassAggDer(int, int x = __builtin_LINE()) : AggBase{x} {}
+};
+static_assert(ClassAggDer{}.x == 100, "");
+
+} // namespace test_line
+
+//===----------------------------------------------------------------------===//
+//                            __builtin_FILE()
+//===----------------------------------------------------------------------===//
+
+namespace test_file {
+constexpr const char *test_file_simple(const char *__f = __builtin_FILE()) {
+  return __f;
+}
+void test_function() {
+#line 900
+  static_assert(is_equal(test_file_simple(), __FILE__));
+  static_assert(is_equal(SLF::test_function().file(), __FILE__), "");
+  static_assert(is_equal(SLF::test_function_template(42).file(), __FILE__), "");
+
+  static_assert(is_equal(SLF::test_function_indirect().file(), SLF::global_info.file()), "");
+  static_assert(is_equal(SLF::test_function_template_indirect(42).file(), SLF::global_info.file()), "");
+
+  static_assert(test_file_simple() != nullptr);
+  static_assert(!is_equal(test_file_simple(), "source_location.cpp"));
+}
+
+void test_class() {
+#line 315
+  using SLF::TestClass;
+  constexpr TestClass Default;
+  constexpr TestClass InParam{42};
+  constexpr TestClass Template{42, 42};
+  constexpr auto *F = Default.info.file();
+  constexpr auto Char = F[0];
+  static_assert(is_equal(Default.info.file(), SLF::FILE), "");
+  static_assert(is_equal(InParam.info.file(), SLF::FILE), "");
+  static_assert(is_equal(InParam.ctor_info.file(), __FILE__), "");
+}
+
+void test_aggr_class() {
+  using Agg = SLF::AggrClass<>;
+  constexpr Agg Default{};
+  constexpr Agg InitOne{42};
+  static_assert(is_equal(Default.init_info.file(), __FILE__), "");
+  static_assert(is_equal(InitOne.init_info.file(), __FILE__), "");
+}
+
+} // namespace test_file
+
+//===----------------------------------------------------------------------===//
+//                            __builtin_FUNCTION()
+//===----------------------------------------------------------------------===//
+
+namespace test_func {
+
+constexpr const char *test_func_simple(const char *__f = __builtin_FUNCTION()) {
+  return __f;
+}
+constexpr const char *get_function() {
+  return __func__;
+}
+constexpr bool test_function() {
+  return is_equal(__func__, test_func_simple()) &&
+         !is_equal(get_function(), test_func_simple());
+}
+static_assert(test_function());
+
+template <class T, class U = SL>
+constexpr Pair<U, U> test_func_template(T, U u = U::current()) {
+  static_assert(is_equal(__func__, U::current().function()));
+  return {u, U::current()};
+}
+template <class T>
+void func_template_tests() {
+  constexpr auto P = test_func_template(42);
+  //static_assert(is_equal(P.first.function(), __func__), "");
+  //static_assert(!is_equal(P.second.function(), __func__), "");
+}
+template void func_template_tests<int>();
+
+template <class = int, class T = SL>
+struct TestCtor {
+  T info = T::current();
+  T ctor_info;
+  TestCtor() = default;
+  template <class U = SL>
+  constexpr TestCtor(int, U u = U::current()) : ctor_info(u) {}
+};
+void ctor_tests() {
+  constexpr TestCtor<> Default;
+  constexpr TestCtor<> Template{42};
+  static_assert(!is_equal(Default.info.function(), __func__));
+  static_assert(is_equal(Default.info.function(), "TestCtor"));
+  static_assert(is_equal(Template.info.function(), "TestCtor"));
+  static_assert(is_equal(Template.ctor_info.function(), __func__));
+}
+
+constexpr SL global_sl = SL::current();
+static_assert(is_equal(global_sl.function(), ""));
+
+} // namespace test_func
+
+//===----------------------------------------------------------------------===//
+//                            __builtin_COLUMN()
+//===----------------------------------------------------------------------===//
+
+namespace test_column {
+
+// clang-format off
+constexpr bool test_column_fn() {
+  constexpr SL S = SL::current();
+  static_assert(S.line() == (__LINE__ - 1), "");
+  constexpr int Indent = 4;
+  {
+    // The start of the call expression to `current()` begins at the token `SL`
+    constexpr int ExpectCol = Indent + 3;
+    constexpr SL S2
+     =
+      SL // Call expression starts here
+        ::
+          current
+                 (
+
+                  )
+                   ;
+    static_assert(S2.column() == ExpectCol, "");
+  }
+  {
+    constexpr int ExpectCol = 2;
+    constexpr int C =
+ __builtin_COLUMN // Expect call expression to start here
+      ();
+    static_assert(C == ExpectCol);
+  }
+  return true;
+}
+#line 420
+static_assert(test_column_fn());
+
+// Test that the column matches the start of the call expression 'SL::current()'
+static_assert(SL::current().column() == __builtin_strlen("static_assert(S"));
+struct TestClass {
+  int x = __builtin_COLUMN();
+   TestClass() = default; /* indented to 3 spaces for testing */
+  constexpr TestClass(int, int o = __builtin_COLUMN()) : x(o) {}
+};
+struct TestAggClass {
+  int x = __builtin_COLUMN();
+};
+constexpr bool test_class() {
+
+  auto check = [](int V, const char* S, int indent = 4) {
+    assert(V == (__builtin_strlen(S) + indent));
+  };
+  {
+    TestClass t{};
+    check(t.x, "   T", 0); // Start of default constructor decl.
+  }
+  {
+    TestClass t1
+            {42};
+    check(t1.x, "TestClass t"); // Start of variable being constructed.
+  }
+  {
+    TestAggClass t  { };
+    check(t.x, "TestAggClass t  { }");
+  }
+  {
+    TestAggClass t = { };
+    check(t.x, "TestAggClass t = { }");
+  }
+  return true;
+}
+static_assert(test_class());
+// clang-format on
+} // namespace test_column
+
+// Test [reflection.src_loc.creation]p2
+//  >  The value should be affected by #line (C++14 16.4) in the same manner as
+//  >  for __LINE__ and __FILE__.
+namespace test_pragma_line {
+constexpr int StartLine = 42;
+#line 42
+static_assert(__builtin_LINE() == StartLine);
+static_assert(__builtin_LINE() == StartLine + 1);
+static_assert(SL::current().line() == StartLine + 2);
+#line 44 "test_file.c"
+static_assert(is_equal("test_file.c", __FILE__));
+static_assert(is_equal("test_file.c", __builtin_FILE()));
+static_assert(is_equal("test_file.c", SL::current().file()));
+static_assert(is_equal("test_file.c", SLF::test_function().file()));
+static_assert(is_equal(SLF::FILE, SLF::test_function_indirect().file()));
+} // end namespace test_pragma_line
+
+namespace test_out_of_line_init {
+#line 4000 "test_out_of_line_init.cpp"
+constexpr unsigned get_line(unsigned n = __builtin_LINE()) { return n; }
+constexpr const char *get_file(const char *f = __builtin_FILE()) { return f; }
+constexpr const char *get_func(const char *f = __builtin_FUNCTION()) { return f; }
+#line 4100 "A.cpp"
+struct A {
+  int n = __builtin_LINE();
+  int n2 = get_line();
+  const char *f = __builtin_FILE();
+  const char *f2 = get_file();
+  const char *func = __builtin_FUNCTION();
+  const char *func2 = get_func();
+  SL info = SL::current();
+};
+#line 4200 "B.cpp"
+struct B {
+  A a = {};
+};
+#line 4300 "test_passed.cpp"
+constexpr B b = {};
+static_assert(b.a.n == 4300, "");
+static_assert(b.a.n2 == 4300, "");
+static_assert(b.a.info.line() == 4300, "");
+static_assert(is_equal(b.a.f, "test_passed.cpp"));
+static_assert(is_equal(b.a.f2, "test_passed.cpp"));
+static_assert(is_equal(b.a.info.file(), "test_passed.cpp"));
+static_assert(is_equal(b.a.func, ""));
+static_assert(is_equal(b.a.func2, ""));
+static_assert(is_equal(b.a.info.function(), ""));
+
+constexpr bool test_in_func() {
+#line 4400 "test_func_passed.cpp"
+  constexpr B b = {};
+  static_assert(b.a.n == 4400, "");
+  static_assert(b.a.n2 == 4400, "");
+  static_assert(b.a.info.line() == 4400, "");
+  static_assert(is_equal(b.a.f, "test_func_passed.cpp"));
+  static_assert(is_equal(b.a.f2, "test_func_passed.cpp"));
+  static_assert(is_equal(b.a.info.file(), "test_func_passed.cpp"));
+  static_assert(is_equal(b.a.func, "test_in_func"));
+  static_assert(is_equal(b.a.func2, "test_in_func"));
+  static_assert(is_equal(b.a.info.function(), "test_in_func"));
+  return true;
+}
+static_assert(test_in_func());
+
+} // end namespace test_out_of_line_init
+
+namespace test_global_scope {
+#line 5000 "test_global_scope.cpp"
+constexpr unsigned get_line(unsigned n = __builtin_LINE()) { return n; }
+constexpr const char *get_file(const char *f = __builtin_FILE()) { return f; }
+constexpr const char *get_func(const char *f = __builtin_FUNCTION()) { return f; }
+#line 5100
+struct InInit {
+  unsigned l = get_line();
+  const char *f = get_file();
+  const char *func = get_func();
+
+#line 5200 "in_init.cpp"
+  constexpr InInit() {}
+};
+#line 5300
+constexpr InInit II;
+
+static_assert(II.l == 5200, "");
+static_assert(is_equal(II.f, "in_init.cpp"));
+static_assert(is_equal(II.func, "InInit"));
+
+#line 5400
+struct AggInit {
+  unsigned l = get_line();
+  const char *f = get_file();
+  const char *func = get_func();
+};
+#line 5500 "brace_init.cpp"
+constexpr AggInit AI = {};
+static_assert(AI.l == 5500);
+static_assert(is_equal(AI.f, "brace_init.cpp"));
+static_assert(is_equal(AI.func, ""));
+
+} // namespace test_global_scope
+
+namespace TestFuncInInit {
+#line 6000 "InitClass.cpp"
+struct Init {
+  SL info;
+#line 6100 "InitCtor.cpp"
+  constexpr Init(SL info = SL::current()) : info(info) {}
+};
+#line 6200 "InitGlobal.cpp"
+constexpr Init I;
+static_assert(I.info.line() == 6200);
+static_assert(is_equal(I.info.file(), "InitGlobal.cpp"));
+
+} // namespace TestFuncInInit
+
+namespace TestConstexprContext {
+#line 7000 "TestConstexprContext.cpp"
+  constexpr const char* foo() { return __builtin_FILE(); }
+#line 7100 "Bar.cpp"
+  constexpr const char* bar(const char* x = foo()) { return x; }
+  constexpr bool test() {
+    static_assert(is_equal(bar(), "TestConstexprContext.cpp"));
+    return true;
+  }
+  static_assert(test());
+}

tools/libclang/CXCursor.cpp

@@ -282,6 +282,7 @@ CXCursor cxcursor::MakeCXCursor(const Stmt *S, const Decl *Parent,
   case Stmt::ParenListExprClass:
   case Stmt::PredefinedExprClass:
   case Stmt::ShuffleVectorExprClass:
+  case Stmt::SourceLocExprClass:
   case Stmt::ConvertVectorExprClass:
   case Stmt::VAArgExprClass:
   case Stmt::ObjCArrayLiteralClass: