diff --git a/clang-tools-extra/clang-tidy/readability/IdentifierNamingCheck.cpp b/clang-tools-extra/clang-tidy/readability/IdentifierNamingCheck.cpp
index d716977d0501..2e4e3fe196de 100644
--- a/clang-tools-extra/clang-tidy/readability/IdentifierNamingCheck.cpp
+++ b/clang-tools-extra/clang-tidy/readability/IdentifierNamingCheck.cpp
@@ -661,7 +661,7 @@ void IdentifierNamingCheck::onEndOfTranslationUnit() {
       continue;
 
     if (Failure.ShouldFix) {
-      auto Diag = diag(Decl.getLocStart(), "invalid case style for %0 '%1'")
+      auto Diag = diag(Decl.getLocation(), "invalid case style for %0 '%1'")
                   << Failure.KindName << Decl.getName();
 
       for (const auto &Loc : Failure.RawUsageLocs) {
diff --git a/clang-tools-extra/test/clang-tidy/readability-identifier-naming.cpp b/clang-tools-extra/test/clang-tidy/readability-identifier-naming.cpp
index cd7e46119470..1237cca7c9b9 100644
--- a/clang-tools-extra/test/clang-tidy/readability-identifier-naming.cpp
+++ b/clang-tools-extra/test/clang-tidy/readability-identifier-naming.cpp
@@ -74,10 +74,10 @@
 // the -header-filter= option
 
 namespace FOO_NS {
-// CHECK-MESSAGES: :[[@LINE-1]]:1: warning: invalid case style for namespace 'FOO_NS' [readability-identifier-naming]
+// CHECK-MESSAGES: :[[@LINE-1]]:11: warning: invalid case style for namespace 'FOO_NS' [readability-identifier-naming]
 // CHECK-FIXES: {{^}}namespace foo_ns {{{$}}
 inline namespace InlineNamespace {
-// CHECK-MESSAGES: :[[@LINE-1]]:1: warning: invalid case style for inline namespace 'InlineNamespace'
+// CHECK-MESSAGES: :[[@LINE-1]]:18: warning: invalid case style for inline namespace 'InlineNamespace'
 // CHECK-FIXES: {{^}}inline namespace inline_namespace {{{$}}
 
 SYSTEM_NS::structure g_s1;
@@ -102,7 +102,7 @@ BLA;
 // NO warnings or fixes expected as FOO_bar is from macro expansion
 
 enum my_enumeration {
-// CHECK-MESSAGES: :[[@LINE-1]]:1: warning: invalid case style for enum 'my_enumeration'
+// CHECK-MESSAGES: :[[@LINE-1]]:6: warning: invalid case style for enum 'my_enumeration'
 // CHECK-FIXES: {{^}}enum EMyEnumeration {{{$}}
     MyConstant = 1,
 // CHECK-MESSAGES: :[[@LINE-1]]:5: warning: invalid case style for enum constant 'MyConstant'
@@ -116,11 +116,11 @@ enum my_enumeration {
 };
 
 constexpr int ConstExpr_variable = MyConstant;
-// CHECK-MESSAGES: :[[@LINE-1]]:1: warning: invalid case style for constexpr variable 'ConstExpr_variable'
+// CHECK-MESSAGES: :[[@LINE-1]]:15: warning: invalid case style for constexpr variable 'ConstExpr_variable'
 // CHECK-FIXES: {{^}}constexpr int const_expr_variable = MY_CONSTANT;{{$}}
 
 class my_class {
-// CHECK-MESSAGES: :[[@LINE-1]]:1: warning: invalid case style for class 'my_class'
+// CHECK-MESSAGES: :[[@LINE-1]]:7: warning: invalid case style for class 'my_class'
 // CHECK-FIXES: {{^}}class CMyClass {{{$}}
     my_class();
 // CHECK-FIXES: {{^}}    CMyClass();{{$}}
@@ -132,62 +132,62 @@ class my_class {
 // CHECK-FIXES: {{^}}      CMyClass();{{$}}
 
   const int MEMBER_one_1 = ConstExpr_variable;
-// CHECK-MESSAGES: :[[@LINE-1]]:3: warning: invalid case style for constant member 'MEMBER_one_1'
+// CHECK-MESSAGES: :[[@LINE-1]]:13: warning: invalid case style for constant member 'MEMBER_one_1'
 // CHECK-FIXES: {{^}}  const int member_one_1 = const_expr_variable;{{$}}
   int member2 = 2;
-// CHECK-MESSAGES: :[[@LINE-1]]:3: warning: invalid case style for private member 'member2'
+// CHECK-MESSAGES: :[[@LINE-1]]:7: warning: invalid case style for private member 'member2'
 // CHECK-FIXES: {{^}}  int __member2 = 2;{{$}}
 
 private:
     int private_member = 3;
-// CHECK-MESSAGES: :[[@LINE-1]]:5: warning: invalid case style for private member 'private_member'
+// CHECK-MESSAGES: :[[@LINE-1]]:9: warning: invalid case style for private member 'private_member'
 // CHECK-FIXES: {{^}}    int __private_member = 3;{{$}}
 
 protected:
     int ProtMember;
-// CHECK-MESSAGES: :[[@LINE-1]]:5: warning: invalid case style for protected member 'ProtMember'
+// CHECK-MESSAGES: :[[@LINE-1]]:9: warning: invalid case style for protected member 'ProtMember'
 // CHECK-FIXES: {{^}}    int _ProtMember;{{$}}
 
 public:
     int PubMem;
-// CHECK-MESSAGES: :[[@LINE-1]]:5: warning: invalid case style for public member 'PubMem'
+// CHECK-MESSAGES: :[[@LINE-1]]:9: warning: invalid case style for public member 'PubMem'
 // CHECK-FIXES: {{^}}    int pub_mem;{{$}}
 
     static const int classConstant;
-// CHECK-MESSAGES: :[[@LINE-1]]:5: warning: invalid case style for class constant 'classConstant'
+// CHECK-MESSAGES: :[[@LINE-1]]:22: warning: invalid case style for class constant 'classConstant'
 // CHECK-FIXES: {{^}}    static const int kClassConstant;{{$}}
     static int ClassMember_2;
-// CHECK-MESSAGES: :[[@LINE-1]]:5: warning: invalid case style for class member 'ClassMember_2'
+// CHECK-MESSAGES: :[[@LINE-1]]:16: warning: invalid case style for class member 'ClassMember_2'
 // CHECK-FIXES: {{^}}    static int ClassMember2;{{$}}
 };
 
 const int my_class::classConstant = 4;
-// CHECK-MESSAGES: :[[@LINE-1]]:1: warning: invalid case style for class constant 'classConstant'
+// CHECK-MESSAGES: :[[@LINE-1]]:21: warning: invalid case style for class constant 'classConstant'
 // CHECK-FIXES: {{^}}const int CMyClass::kClassConstant = 4;{{$}}
 
 int my_class::ClassMember_2 = 5;
-// CHECK-MESSAGES: :[[@LINE-1]]:1: warning: invalid case style for class member 'ClassMember_2'
+// CHECK-MESSAGES: :[[@LINE-1]]:15: warning: invalid case style for class member 'ClassMember_2'
 // CHECK-FIXES: {{^}}int CMyClass::ClassMember2 = 5;{{$}}
 
 class my_derived_class : public virtual my_class {};
-// CHECK-MESSAGES: :[[@LINE-1]]:1: warning: invalid case style for class 'my_derived_class'
+// CHECK-MESSAGES: :[[@LINE-1]]:7: warning: invalid case style for class 'my_derived_class'
 // CHECK-FIXES: {{^}}class CMyDerivedClass : public virtual CMyClass {};{{$}}
 
 class CMyWellNamedClass {};
 // No warning expected as this class is well named.
 
 template<typename T>
-// CHECK-MESSAGES: :[[@LINE-1]]:10: warning: invalid case style for type template parameter 'T'
+// CHECK-MESSAGES: :[[@LINE-1]]:19: warning: invalid case style for type template parameter 'T'
 // CHECK-FIXES: {{^}}template<typename t_t>{{$}}
 class my_templated_class : CMyWellNamedClass {};
-// CHECK-MESSAGES: :[[@LINE-1]]:1: warning: invalid case style for class 'my_templated_class'
+// CHECK-MESSAGES: :[[@LINE-1]]:7: warning: invalid case style for class 'my_templated_class'
 // CHECK-FIXES: {{^}}class CMyTemplatedClass : CMyWellNamedClass {};{{$}}
 
 template<typename T>
-// CHECK-MESSAGES: :[[@LINE-1]]:10: warning: invalid case style for type template parameter 'T'
+// CHECK-MESSAGES: :[[@LINE-1]]:19: warning: invalid case style for type template parameter 'T'
 // CHECK-FIXES: {{^}}template<typename t_t>{{$}}
 class my_other_templated_class : my_templated_class<  my_class>, private my_derived_class {};
-// CHECK-MESSAGES: :[[@LINE-1]]:1: warning: invalid case style for class 'my_other_templated_class'
+// CHECK-MESSAGES: :[[@LINE-1]]:7: warning: invalid case style for class 'my_other_templated_class'
 // CHECK-FIXES: {{^}}class CMyOtherTemplatedClass : CMyTemplatedClass<  CMyClass>, private CMyDerivedClass {};{{$}}
 
 template<typename t_t>
@@ -195,32 +195,32 @@ using MYSUPER_TPL = my_other_templated_class  <:: FOO_NS  ::my_class>;
 // CHECK-FIXES: {{^}}using MYSUPER_TPL = CMyOtherTemplatedClass  <:: foo_ns  ::CMyClass>;{{$}}
 
 const int global_Constant = 6;
-// CHECK-MESSAGES: :[[@LINE-1]]:1: warning: invalid case style for global constant 'global_Constant'
+// CHECK-MESSAGES: :[[@LINE-1]]:11: warning: invalid case style for global constant 'global_Constant'
 // CHECK-FIXES: {{^}}const int GLOBAL_CONSTANT = 6;{{$}}
 int Global_variable = 7;
-// CHECK-MESSAGES: :[[@LINE-1]]:1: warning: invalid case style for global variable 'Global_variable'
+// CHECK-MESSAGES: :[[@LINE-1]]:5: warning: invalid case style for global variable 'Global_variable'
 // CHECK-FIXES: {{^}}int g_global_variable = 7;{{$}}
 
 void global_function(int PARAMETER_1, int const CONST_parameter) {
-// CHECK-MESSAGES: :[[@LINE-1]]:1: warning: invalid case style for global function 'global_function'
-// CHECK-MESSAGES: :[[@LINE-2]]:22: warning: invalid case style for parameter 'PARAMETER_1'
-// CHECK-MESSAGES: :[[@LINE-3]]:39: warning: invalid case style for constant parameter 'CONST_parameter'
+// CHECK-MESSAGES: :[[@LINE-1]]:6: warning: invalid case style for global function 'global_function'
+// CHECK-MESSAGES: :[[@LINE-2]]:26: warning: invalid case style for parameter 'PARAMETER_1'
+// CHECK-MESSAGES: :[[@LINE-3]]:49: warning: invalid case style for constant parameter 'CONST_parameter'
 // CHECK-FIXES: {{^}}void GlobalFunction(int a_parameter1, int const i_constParameter) {{{$}}
     static const int THIS_static_ConsTant = 4;
-// CHECK-MESSAGES: :[[@LINE-1]]:5: warning: invalid case style for static constant 'THIS_static_ConsTant'
+// CHECK-MESSAGES: :[[@LINE-1]]:22: warning: invalid case style for static constant 'THIS_static_ConsTant'
 // CHECK-FIXES: {{^}}    static const int THIS_STATIC_CONS_TANT = 4;{{$}}
     static int THIS_static_variable;
-// CHECK-MESSAGES: :[[@LINE-1]]:5: warning: invalid case style for static variable 'THIS_static_variable'
+// CHECK-MESSAGES: :[[@LINE-1]]:16: warning: invalid case style for static variable 'THIS_static_variable'
 // CHECK-FIXES: {{^}}    static int s_thisStaticVariable;{{$}}
     int const local_Constant = 3;
-// CHECK-MESSAGES: :[[@LINE-1]]:5: warning: invalid case style for local constant 'local_Constant'
+// CHECK-MESSAGES: :[[@LINE-1]]:15: warning: invalid case style for local constant 'local_Constant'
 // CHECK-FIXES: {{^}}    int const kLocalConstant = 3;{{$}}
     int LOCAL_VARIABLE;
-// CHECK-MESSAGES: :[[@LINE-1]]:5: warning: invalid case style for local variable 'LOCAL_VARIABLE'
+// CHECK-MESSAGES: :[[@LINE-1]]:9: warning: invalid case style for local variable 'LOCAL_VARIABLE'
 // CHECK-FIXES: {{^}}    int local_variable;{{$}}
 
     int LOCAL_Array__[] = {0, 1, 2};
-// CHECK-MESSAGES: :[[@LINE-1]]:5: warning: invalid case style for local variable 'LOCAL_Array__'
+// CHECK-MESSAGES: :[[@LINE-1]]:9: warning: invalid case style for local variable 'LOCAL_Array__'
 // CHECK-FIXES: {{^}}    int local_array[] = {0, 1, 2};{{$}}
 
     for (auto _ : LOCAL_Array__) {
@@ -228,11 +228,11 @@ void global_function(int PARAMETER_1, int const CONST_parameter) {
 }
 
 template<typename ... TYPE_parameters>
-// CHECK-MESSAGES: :[[@LINE-1]]:10: warning: invalid case style for type template parameter 'TYPE_parameters'
+// CHECK-MESSAGES: :[[@LINE-1]]:23: warning: invalid case style for type template parameter 'TYPE_parameters'
 // CHECK-FIXES: {{^}}template<typename ... typeParameters_t>{{$}}
 void Global_Fun(TYPE_parameters... PARAMETER_PACK) {
-// CHECK-MESSAGES: :[[@LINE-1]]:1: warning: invalid case style for global function 'Global_Fun'
-// CHECK-MESSAGES: :[[@LINE-2]]:17: warning: invalid case style for parameter pack 'PARAMETER_PACK'
+// CHECK-MESSAGES: :[[@LINE-1]]:6: warning: invalid case style for global function 'Global_Fun'
+// CHECK-MESSAGES: :[[@LINE-2]]:36: warning: invalid case style for parameter pack 'PARAMETER_PACK'
 // CHECK-FIXES: {{^}}void GlobalFun(typeParameters_t... parameterPack) {{{$}}
     global_function(1, 2);
 // CHECK-FIXES: {{^}}    GlobalFunction(1, 2);{{$}}
@@ -242,71 +242,71 @@ void Global_Fun(TYPE_parameters... PARAMETER_PACK) {
 }
 
 template<template<typename> class TPL_parameter, int COUNT_params, typename ... TYPE_parameters>
-// CHECK-MESSAGES: :[[@LINE-1]]:10: warning: invalid case style for template template parameter 'TPL_parameter'
-// CHECK-MESSAGES: :[[@LINE-2]]:50: warning: invalid case style for value template parameter 'COUNT_params'
-// CHECK-MESSAGES: :[[@LINE-3]]:68: warning: invalid case style for type template parameter 'TYPE_parameters'
+// CHECK-MESSAGES: :[[@LINE-1]]:35: warning: invalid case style for template template parameter 'TPL_parameter'
+// CHECK-MESSAGES: :[[@LINE-2]]:54: warning: invalid case style for value template parameter 'COUNT_params'
+// CHECK-MESSAGES: :[[@LINE-3]]:81: warning: invalid case style for type template parameter 'TYPE_parameters'
 // CHECK-FIXES: {{^}}template<template<typename> class TplParameter, int countParams, typename ... typeParameters_t>{{$}}
 class test_CLASS {
-// CHECK-MESSAGES: :[[@LINE-1]]:1: warning: invalid case style for class 'test_CLASS'
+// CHECK-MESSAGES: :[[@LINE-1]]:7: warning: invalid case style for class 'test_CLASS'
 // CHECK-FIXES: {{^}}class CTestClass {{{$}}
 };
 
 class abstract_class {
-// CHECK-MESSAGES: :[[@LINE-1]]:1: warning: invalid case style for abstract class 'abstract_class'
+// CHECK-MESSAGES: :[[@LINE-1]]:7: warning: invalid case style for abstract class 'abstract_class'
 // CHECK-FIXES: {{^}}class AAbstractClass {{{$}}
     virtual ~abstract_class() = 0;
 // CHECK-FIXES: {{^}}    virtual ~AAbstractClass() = 0;{{$}}
     virtual void VIRTUAL_METHOD();
-// CHECK-MESSAGES: :[[@LINE-1]]:5: warning: invalid case style for virtual method 'VIRTUAL_METHOD'
+// CHECK-MESSAGES: :[[@LINE-1]]:18: warning: invalid case style for virtual method 'VIRTUAL_METHOD'
 // CHECK-FIXES: {{^}}    virtual void v_VIRTUAL_METHOD();{{$}}
     void non_Virtual_METHOD() {}
-// CHECK-MESSAGES: :[[@LINE-1]]:5: warning: invalid case style for private method 'non_Virtual_METHOD'
+// CHECK-MESSAGES: :[[@LINE-1]]:10: warning: invalid case style for private method 'non_Virtual_METHOD'
 // CHECK-FIXES: {{^}}    void __non_Virtual_METHOD() {}{{$}}
 
 public:
     static void CLASS_METHOD() {}
-// CHECK-MESSAGES: :[[@LINE-1]]:5: warning: invalid case style for class method 'CLASS_METHOD'
+// CHECK-MESSAGES: :[[@LINE-1]]:17: warning: invalid case style for class method 'CLASS_METHOD'
 // CHECK-FIXES: {{^}}    static void classMethod() {}{{$}}
 
     constexpr int CST_expr_Method() { return 2; }
-// CHECK-MESSAGES: :[[@LINE-1]]:5: warning: invalid case style for constexpr method 'CST_expr_Method'
+// CHECK-MESSAGES: :[[@LINE-1]]:19: warning: invalid case style for constexpr method 'CST_expr_Method'
 // CHECK-FIXES: {{^}}    constexpr int cst_expr_method() { return 2; }{{$}}
 
 private:
     void PRIVate_Method();
-// CHECK-MESSAGES: :[[@LINE-1]]:5: warning: invalid case style for private method 'PRIVate_Method'
+// CHECK-MESSAGES: :[[@LINE-1]]:10: warning: invalid case style for private method 'PRIVate_Method'
 // CHECK-FIXES: {{^}}    void __PRIVate_Method();{{$}}
 protected:
     void protected_Method();
-// CHECK-MESSAGES: :[[@LINE-1]]:5: warning: invalid case style for protected method 'protected_Method'
+// CHECK-MESSAGES: :[[@LINE-1]]:10: warning: invalid case style for protected method 'protected_Method'
 // CHECK-FIXES: {{^}}    void _protected_Method();{{$}}
 public:
     void public_Method();
-// CHECK-MESSAGES: :[[@LINE-1]]:5: warning: invalid case style for method 'public_Method'
+// CHECK-MESSAGES: :[[@LINE-1]]:10: warning: invalid case style for method 'public_Method'
 // CHECK-FIXES: {{^}}    void publicMethod();{{$}}
 };
 
 constexpr int CE_function() { return 3; }
-// CHECK-MESSAGES: :[[@LINE-1]]:1: warning: invalid case style for constexpr function 'CE_function'
+// CHECK-MESSAGES: :[[@LINE-1]]:15: warning: invalid case style for constexpr function 'CE_function'
 // CHECK-FIXES: {{^}}constexpr int ce_function() { return 3; }{{$}}
 
 struct THIS___Structure {
-// CHECK-MESSAGES: :[[@LINE-1]]:1: warning: invalid case style for struct 'THIS___Structure'
+// CHECK-MESSAGES: :[[@LINE-1]]:8: warning: invalid case style for struct 'THIS___Structure'
 // CHECK-FIXES: {{^}}struct this_structure {{{$}}
     THIS___Structure();
 // CHECK-FIXES: {{^}}    this_structure();{{$}}
 
   union __MyUnion_is_wonderful__ {};
-// CHECK-MESSAGES: :[[@LINE-1]]:3: warning: invalid case style for union '__MyUnion_is_wonderful__'
+// CHECK-MESSAGES: :[[@LINE-1]]:9: warning: invalid case style for union '__MyUnion_is_wonderful__'
 // CHECK-FIXES: {{^}}  union UMyUnionIsWonderful {};{{$}}
 };
 
 typedef THIS___Structure struct_type;
-// CHECK-MESSAGES: :[[@LINE-1]]:1: warning: invalid case style for typedef 'struct_type'
+// CHECK-MESSAGES: :[[@LINE-1]]:26: warning: invalid case style for typedef 'struct_type'
 // CHECK-FIXES: {{^}}typedef this_structure struct_type_t;{{$}}
 
 static void static_Function() {
-// CHECK-MESSAGES: :[[@LINE-1]]:1: warning: invalid case style for function 'static_Function'
+// CHECK-MESSAGES: :[[@LINE-1]]:13: warning: invalid case style for function 'static_Function'
 // CHECK-FIXES: {{^}}static void staticFunction() {{{$}}
 
   ::FOO_NS::InlineNamespace::abstract_class::CLASS_METHOD();