Index: clang-tools-extra/trunk/clang-tidy/modernize/UseDefaultCheck.cpp
===================================================================
--- clang-tools-extra/trunk/clang-tidy/modernize/UseDefaultCheck.cpp
+++ clang-tools-extra/trunk/clang-tidy/modernize/UseDefaultCheck.cpp
@@ -20,37 +20,6 @@
 
 static const char SpecialFunction[] = "SpecialFunction";
 
-/// \brief Finds the SourceLocation of the colon ':' before the initialization
-/// list in the definition of a constructor.
-static SourceLocation getColonLoc(const ASTContext *Context,
-                                  const CXXConstructorDecl *Ctor) {
-  // FIXME: First init is the first initialization that is going to be
-  // performed, no matter what was the real order in the source code. If the
-  // order of the inits is wrong in the code, it may result in a false negative.
-  SourceLocation FirstInit = (*Ctor->init_begin())->getSourceLocation();
-  SourceLocation LastArg =
-      Ctor->getParamDecl(Ctor->getNumParams() - 1)->getLocEnd();
-  // We need to find the colon between the ')' and the first initializer.
-  bool Invalid = false;
-  StringRef Text = Lexer::getSourceText(
-      CharSourceRange::getCharRange(LastArg, FirstInit),
-      Context->getSourceManager(), Context->getLangOpts(), &Invalid);
-  if (Invalid)
-    return SourceLocation();
-
-  size_t ColonPos = Text.rfind(':');
-  if (ColonPos == StringRef::npos)
-    return SourceLocation();
-
-  Text = Text.drop_front(ColonPos + 1);
-  if (std::strspn(Text.data(), " \t\r\n") != Text.size()) {
-    // If there are comments, preprocessor directives or anything, abort.
-    return SourceLocation();
-  }
-  // FIXME: don't remove comments in the middle of the initializers.
-  return LastArg.getLocWithOffset(ColonPos);
-}
-
 /// \brief Finds all the named non-static fields of \p Record.
 static std::set<const FieldDecl *>
 getAllNamedFields(const CXXRecordDecl *Record) {
@@ -262,7 +231,6 @@
 
 void UseDefaultCheck::check(const MatchFinder::MatchResult &Result) {
   std::string SpecialFunctionName;
-  SourceLocation StartLoc, EndLoc;
 
   // Both CXXConstructorDecl and CXXDestructorDecl inherit from CXXMethodDecl.
   const auto *SpecialFunctionDecl =
@@ -280,15 +248,13 @@
   if (!Body)
     return;
 
-  // Default locations.
-  StartLoc = Body->getLBracLoc();
-  EndLoc = Body->getRBracLoc();
-
   // If there are comments inside the body, don't do the change.
   if (!SpecialFunctionDecl->isCopyAssignmentOperator() &&
       !bodyEmpty(Result.Context, Body))
     return;
 
+  std::vector<FixItHint> RemoveInitializers;
+
   if (const auto *Ctor = dyn_cast<CXXConstructorDecl>(SpecialFunctionDecl)) {
     if (Ctor->getNumParams() == 0) {
       SpecialFunctionName = "default constructor";
@@ -297,10 +263,9 @@
         return;
       SpecialFunctionName = "copy constructor";
       // If there are constructor initializers, they must be removed.
-      if (Ctor->getNumCtorInitializers() != 0) {
-        StartLoc = getColonLoc(Result.Context, Ctor);
-        if (!StartLoc.isValid())
-          return;
+      for (const CXXCtorInitializer *Init : Ctor->inits()) {
+        RemoveInitializers.emplace_back(
+            FixItHint::CreateRemoval(Init->getSourceRange()));
       }
     }
   } else if (isa<CXXDestructorDecl>(SpecialFunctionDecl)) {
@@ -313,8 +278,8 @@
 
   diag(SpecialFunctionDecl->getLocStart(),
        "use '= default' to define a trivial " + SpecialFunctionName)
-      << FixItHint::CreateReplacement(
-          CharSourceRange::getTokenRange(StartLoc, EndLoc), "= default;");
+      << FixItHint::CreateReplacement(Body->getSourceRange(), "= default;")
+      << RemoveInitializers;
 }
 
 } // namespace modernize
Index: clang-tools-extra/trunk/test/clang-tidy/modernize-use-default-copy.cpp
===================================================================
--- clang-tools-extra/trunk/test/clang-tidy/modernize-use-default-copy.cpp
+++ clang-tools-extra/trunk/test/clang-tidy/modernize-use-default-copy.cpp
@@ -8,7 +8,7 @@
 };
 OL::OL(const OL &Other) : Field(Other.Field) {}
 // CHECK-MESSAGES: :[[@LINE-1]]:1: warning: use '= default' to define a trivial copy constructor [modernize-use-default]
-// CHECK-FIXES: OL::OL(const OL &Other) = default;
+// CHECK-FIXES: OL::OL(const OL &Other)  = default;
 OL &OL::operator=(const OL &Other) {
   Field = Other.Field;
   return *this;
@@ -20,7 +20,7 @@
 struct IL {
   IL(const IL &Other) : Field(Other.Field) {}
   // CHECK-MESSAGES: :[[@LINE-1]]:3: warning: use '= default'
-  // CHECK-FIXES: IL(const IL &Other) = default;
+  // CHECK-FIXES: IL(const IL &Other)  = default;
   IL &operator=(const IL &Other) {
     Field = Other.Field;
     return *this;
@@ -43,7 +43,8 @@
                             Mutable(Other.Mutable), Reference(Other.Reference),
                             Const(Other.Const) {}
   // CHECK-MESSAGES: :[[@LINE-3]]:3: warning: use '= default'
-  // CHECK-FIXES: Qual(const Qual &Other) = default;
+  // CHECK-FIXES: Qual(const Qual &Other)
+  // CHECK-FIXES:                          = default;
 
   int Field;
   volatile char Volatile;
@@ -80,6 +81,8 @@
 struct Comments {
   Comments(const Comments &Other)
       /* don't delete */ : /* this comment */ Field(Other.Field) {}
+  // CHECK-MESSAGES: :[[@LINE-2]]:3: warning: use '= default'
+  // CHECK-FIXES: /* don't delete */  = default;
   int Field;
 };
 
@@ -95,7 +98,7 @@
 struct ColonInComment {
   ColonInComment(const ColonInComment &Other) /* : */ : Field(Other.Field) {}
   // CHECK-MESSAGES: :[[@LINE-1]]:3: warning: use '= default'
-  // CHECK-FIXES: ColonInComment(const ColonInComment &Other) /* : */ = default;
+  // CHECK-FIXES: ColonInComment(const ColonInComment &Other) /* : */  = default;
   int Field;
 };
 
@@ -116,7 +119,8 @@
   BF(const BF &Other) : Field1(Other.Field1), Field2(Other.Field2), Field3(Other.Field3),
                         Field4(Other.Field4) {}
   // CHECK-MESSAGES: :[[@LINE-2]]:3: warning: use '= default'
-  // CHECK-FIXES: BF(const BF &Other) = default;
+  // CHECK-FIXES: BF(const BF &Other) {{$}}
+  // CHECK-FIXES:                     = default;
   BF &operator=(const BF &);
 
   unsigned Field1 : 3;
@@ -140,7 +144,7 @@
 struct BC : IL, OL, BF {
   BC(const BC &Other) : IL(Other), OL(Other), BF(Other) {}
   // CHECK-MESSAGES: :[[@LINE-1]]:3: warning: use '= default'
-  // CHECK-FIXES: BC(const BC &Other) = default;
+  // CHECK-FIXES: BC(const BC &Other)  = default;
   BC &operator=(const BC &Other);
 };
 BC &BC::operator=(const BC &Other) {
@@ -156,7 +160,7 @@
 struct BCWM : IL, OL {
   BCWM(const BCWM &Other) : IL(Other), OL(Other), Bf(Other.Bf) {}
   // CHECK-MESSAGES: :[[@LINE-1]]:3: warning: use '= default'
-  // CHECK-FIXES: BCWM(const BCWM &Other) = default;
+  // CHECK-FIXES: BCWM(const BCWM &Other)  = default;
   BCWM &operator=(const BCWM &);
   BF Bf;
 };
@@ -200,7 +204,7 @@
   // is a virtual OL at the beginning of VA (which is the same).
   VBC(const VBC &Other) : OL(Other), VA(Other), VB(Other) {}
   // CHECK-MESSAGES: :[[@LINE-1]]:3: warning: use '= default'
-  // CHECK-FIXES: VBC(const VBC &Other) = default;
+  // CHECK-FIXES: VBC(const VBC &Other)  = default;
   VBC &operator=(const VBC &Other);
 };
 VBC &VBC::operator=(const VBC &Other) {
@@ -335,7 +339,7 @@
 struct NCRef {
   NCRef(NCRef &Other) : Field1(Other.Field1), Field2(Other.Field2) {}
   // CHECK-MESSAGES: :[[@LINE-1]]:3: warning: use '= default'
-  // CHECK-FIXES: NCRef(NCRef &Other) = default;
+  // CHECK-FIXES: NCRef(NCRef &Other)  = default;
   NCRef &operator=(NCRef &);
   int Field1, Field2;
 };