diff --git a/src/indexer.cc b/src/indexer.cc
index dbea4a53..fa02e8d0 100644
--- a/src/indexer.cc
+++ b/src/indexer.cc
@@ -1376,6 +1376,8 @@ std::vector<std::unique_ptr<IndexedFile>> Parse(IndexerConfig* config, FileConsu
     assert(entry->id_cache.primary_file == entry->path);
     entry->path = NormalizePath(entry->path);
     entry->id_cache.primary_file = entry->path;
+
+    entry->last_modification_time = GetLastModificationTime(entry->path);
   }
 
   // TODO: Fix interesting checks.
diff --git a/src/indexer.h b/src/indexer.h
index 241e5396..a0655c3a 100644
--- a/src/indexer.h
+++ b/src/indexer.h
@@ -466,6 +466,8 @@ struct IndexedFile {
   IdCache id_cache;
 
   std::string path;
+  int64_t last_modification_time = 0;
+
   // The content of |path| when it was indexed.
   //std::string content;
 
diff --git a/src/platform.cc b/src/platform.cc
index e777a8fa..bacb0d7d 100644
--- a/src/platform.cc
+++ b/src/platform.cc
@@ -11,6 +11,8 @@
 
 namespace {
 
+bool gModificationTimeDisabled = false;
+
 // See http://stackoverflow.com/a/236803
 template<typename Out>
 void Split(const std::string &s, char delim, Out result) {
@@ -83,6 +85,15 @@ void MakeDirectoryRecursive(std::string path) {
   }
 }
 
+void DisableModificationTimeForTest() {
+  gModificationTimeDisabled = true;
+}
+
+bool IsModificationTimeDisabledForTests() {
+  return gModificationTimeDisabled;
+}
+
+
 TEST_SUITE("Platform");
 
 TEST_CASE("Split strings") {
diff --git a/src/platform.h b/src/platform.h
index 4b0cdc5b..70db73f6 100644
--- a/src/platform.h
+++ b/src/platform.h
@@ -37,5 +37,10 @@ bool TryMakeDirectory(const std::string& absolute_path);
 
 void SetCurrentThreadName(const std::string& thread_name);
 
+void DisableModificationTimeForTest();
+bool IsModificationTimeDisabledForTests();
+
+int64_t GetLastModificationTime(const std::string& absolute_path);
+
 // Returns any clang arguments that are specific to the current platform.
 std::vector<std::string> GetPlatformClangArguments();
\ No newline at end of file
diff --git a/src/platform_win.cc b/src/platform_win.cc
index ba2c961e..8feda73c 100644
--- a/src/platform_win.cc
+++ b/src/platform_win.cc
@@ -8,6 +8,9 @@
 #include <io.h>
 #include <Windows.h>
 
+#include <sys/types.h>
+#include <sys/stat.h>
+
 #include <algorithm>
 #include <cassert>
 #include <iostream>
@@ -179,6 +182,29 @@ void SetCurrentThreadName(const std::string& thread_name) {
   __except (EXCEPTION_EXECUTE_HANDLER) {}
 }
 
+int64_t GetLastModificationTime(const std::string& absolute_path) {
+  if (IsModificationTimeDisabledForTests())
+    return 1;
+
+  struct _stat buf;
+  if (_stat(absolute_path.c_str(), &buf) != 0) {
+    switch (errno) {
+      case ENOENT:
+        std::cerr << "GetLastModificationTime: unable to find file " << absolute_path << std::endl;
+        break;
+      case EINVAL:
+        std::cerr << "GetLastModificationTime: invalid param to _stat for file file " << absolute_path << std::endl;
+        break;
+      default:
+        std::cerr << "GetLastModificationTime: unhandled for " << absolute_path << std::endl;
+        exit(1);
+        break;
+    }
+  }
+
+  return buf.st_mtime;
+}
+
 std::vector<std::string> GetPlatformClangArguments() {
   return {
     "-fms-compatibility",
diff --git a/src/project.cc b/src/project.cc
index 10787fbb..7f06e08b 100644
--- a/src/project.cc
+++ b/src/project.cc
@@ -104,9 +104,9 @@ CompilationEntry GetCompilationEntryFromCompileCommandEntry(const CompileCommand
   CompilationEntry result;
   result.filename = NormalizePath(entry.file);
 
-  unsigned int num_args = entry.args.size();
+  size_t num_args = entry.args.size();
   result.args.reserve(num_args);
-  for (unsigned int j = 0; j < num_args; ++j) {
+  for (size_t j = 0; j < num_args; ++j) {
     std::string arg = entry.args[j];
 
 
@@ -226,9 +226,9 @@ std::vector<CompilationEntry> LoadCompilationEntriesFromDirectory(const std::str
     entry.file = NormalizePath(absolute_filename);
     entry.directory = directory;
 
-    unsigned int num_args = clang_CompileCommand_getNumArgs(cx_command);
+    unsigned num_args = clang_CompileCommand_getNumArgs(cx_command);
     entry.args.reserve(num_args);
-    for (int i = 0; i < num_args; ++i)
+    for (unsigned i = 0; i < num_args; ++i)
       entry.args.push_back(clang::ToString(clang_CompileCommand_getArg(cx_command, i)));
 
     result.push_back(GetCompilationEntryFromCompileCommandEntry(entry));
diff --git a/src/serializer.cc b/src/serializer.cc
index 63ba2a99..1d761db5 100644
--- a/src/serializer.cc
+++ b/src/serializer.cc
@@ -10,6 +10,13 @@ void Reflect(Reader& visitor, int& value) {
 void Reflect(Writer& visitor, int& value) {
   visitor.Int(value);
 }
+// int64_t
+void Reflect(Reader& visitor, int64_t& value) {
+  value = visitor.GetInt64();
+}
+void Reflect(Writer& visitor, int64_t& value) {
+  visitor.Int64(value);
+}
 // bool
 void Reflect(Reader& visitor, bool& value) {
   value = visitor.GetBool();
@@ -215,6 +222,7 @@ bool ReflectMemberStart(Writer& visitor, IndexedFile& value) {
 template<typename TVisitor>
 void Reflect(TVisitor& visitor, IndexedFile& value) {
   REFLECT_MEMBER_START();
+  REFLECT_MEMBER(last_modification_time);
   REFLECT_MEMBER(dependencies);
   REFLECT_MEMBER(types);
   REFLECT_MEMBER(funcs);
diff --git a/src/serializer.h b/src/serializer.h
index 0c568a32..b41d3be7 100644
--- a/src/serializer.h
+++ b/src/serializer.h
@@ -102,6 +102,9 @@ void ReflectMemberEnd(TVisitor& visitor, T& value) {
 // int
 void Reflect(Reader& visitor, int& value);
 void Reflect(Writer& visitor, int& value);
+// int64_t
+void Reflect(Reader& visitor, int64_t& value);
+void Reflect(Writer& visitor, int64_t& value);
 // bool
 void Reflect(Reader& visitor, bool& value);
 void Reflect(Writer& visitor, bool& value);
diff --git a/src/test.cc b/src/test.cc
index 6a4e8dc4..cdf4bfa8 100644
--- a/src/test.cc
+++ b/src/test.cc
@@ -112,6 +112,8 @@ IndexedFile* FindDbForPathEnding(const std::string& path, const std::vector<std:
 }
 
 void RunTests() {
+  DisableModificationTimeForTest();
+
   // TODO: Assert that we need to be on clang >= 3.9.1
   bool update_all = false;
 
diff --git a/tests/_empty_test.cc b/tests/_empty_test.cc
index 228b2674..4e5cac94 100644
--- a/tests/_empty_test.cc
+++ b/tests/_empty_test.cc
@@ -1,4 +1,6 @@
 /*
 OUTPUT:
-{}
+{
+  "last_modification_time": 1
+}
 */
diff --git a/tests/class_forward_declaration.cc b/tests/class_forward_declaration.cc
index b669f4e9..0d71c8ed 100644
--- a/tests/class_forward_declaration.cc
+++ b/tests/class_forward_declaration.cc
@@ -6,6 +6,7 @@ class Foo;
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@S@Foo",
diff --git a/tests/constructors/constructor.cc b/tests/constructors/constructor.cc
index 3319f23d..a9bf4a00 100644
--- a/tests/constructors/constructor.cc
+++ b/tests/constructors/constructor.cc
@@ -11,6 +11,7 @@ void foo() {
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@S@Foo",
diff --git a/tests/constructors/destructor.cc b/tests/constructors/destructor.cc
index daadd770..a79bee0f 100644
--- a/tests/constructors/destructor.cc
+++ b/tests/constructors/destructor.cc
@@ -16,6 +16,7 @@ void foo() {
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@S@Foo",
diff --git a/tests/constructors/invalid_reference.cc b/tests/constructors/invalid_reference.cc
index fb000dfe..6e95b34f 100644
--- a/tests/constructors/invalid_reference.cc
+++ b/tests/constructors/invalid_reference.cc
@@ -6,6 +6,7 @@ Foo::Foo() {}
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@S@Foo",
diff --git a/tests/declaration_vs_definition/class.cc b/tests/declaration_vs_definition/class.cc
index c7290937..7b3587aa 100644
--- a/tests/declaration_vs_definition/class.cc
+++ b/tests/declaration_vs_definition/class.cc
@@ -8,6 +8,7 @@ class Foo;
 //       for comments.
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@S@Foo",
diff --git a/tests/declaration_vs_definition/class_member.cc b/tests/declaration_vs_definition/class_member.cc
index 5716e0ba..3852fb9f 100644
--- a/tests/declaration_vs_definition/class_member.cc
+++ b/tests/declaration_vs_definition/class_member.cc
@@ -5,6 +5,7 @@ class Foo {
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@S@Foo",
diff --git a/tests/declaration_vs_definition/class_member_static.cc b/tests/declaration_vs_definition/class_member_static.cc
index bb71cea4..f9913040 100644
--- a/tests/declaration_vs_definition/class_member_static.cc
+++ b/tests/declaration_vs_definition/class_member_static.cc
@@ -7,6 +7,7 @@ int Foo::foo;
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@S@Foo",
diff --git a/tests/declaration_vs_definition/func.cc b/tests/declaration_vs_definition/func.cc
index 6770e1b3..37dbfeaf 100644
--- a/tests/declaration_vs_definition/func.cc
+++ b/tests/declaration_vs_definition/func.cc
@@ -7,6 +7,7 @@ void foo();
 // Note: we always use the latest seen ("most local") definition/declaration.
 OUTPUT:
 {
+  "last_modification_time": 1,
   "funcs": [{
       "id": 0,
       "usr": "c:@F@foo#",
diff --git a/tests/declaration_vs_definition/method.cc b/tests/declaration_vs_definition/method.cc
index e587903b..f35a9d14 100644
--- a/tests/declaration_vs_definition/method.cc
+++ b/tests/declaration_vs_definition/method.cc
@@ -9,6 +9,7 @@ void Foo::def() {}
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@S@Foo",
diff --git a/tests/enums/enum_class_decl.cc b/tests/enums/enum_class_decl.cc
index a64669c0..fd38ce39 100644
--- a/tests/enums/enum_class_decl.cc
+++ b/tests/enums/enum_class_decl.cc
@@ -6,6 +6,7 @@ enum class Foo {
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@E@Foo",
diff --git a/tests/enums/enum_decl.cc b/tests/enums/enum_decl.cc
index cbf5deb9..969c8580 100644
--- a/tests/enums/enum_decl.cc
+++ b/tests/enums/enum_decl.cc
@@ -6,6 +6,7 @@ enum Foo {
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@E@Foo",
diff --git a/tests/enums/enum_inherit.cc b/tests/enums/enum_inherit.cc
index b7db7867..4aeffda7 100644
--- a/tests/enums/enum_inherit.cc
+++ b/tests/enums/enum_inherit.cc
@@ -6,6 +6,7 @@ enum Foo : int {
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@E@Foo",
diff --git a/tests/enums/enum_usage.cc b/tests/enums/enum_usage.cc
index e71591ef..4b82acc6 100644
--- a/tests/enums/enum_usage.cc
+++ b/tests/enums/enum_usage.cc
@@ -8,6 +8,7 @@ Foo x = Foo::A;
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@E@Foo",
diff --git a/tests/foobar.cc b/tests/foobar.cc
index 839bf430..a7cf9977 100644
--- a/tests/foobar.cc
+++ b/tests/foobar.cc
@@ -11,6 +11,7 @@ Foo<B> b;
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@E@A",
diff --git a/tests/function_declaration.cc b/tests/function_declaration.cc
index 90dd7e40..928faa46 100644
--- a/tests/function_declaration.cc
+++ b/tests/function_declaration.cc
@@ -3,6 +3,7 @@ void foo(int a, int b);
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "funcs": [{
       "id": 0,
       "usr": "c:@F@foo#I#I#",
diff --git a/tests/function_declaration_definition.cc b/tests/function_declaration_definition.cc
index 669c5575..8d3b5ea7 100644
--- a/tests/function_declaration_definition.cc
+++ b/tests/function_declaration_definition.cc
@@ -5,6 +5,7 @@ void foo() {}
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "funcs": [{
       "id": 0,
       "usr": "c:@F@foo#",
diff --git a/tests/function_definition.cc b/tests/function_definition.cc
index 4def754f..db4bf42e 100644
--- a/tests/function_definition.cc
+++ b/tests/function_definition.cc
@@ -3,6 +3,7 @@ void foo() {}
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "funcs": [{
       "id": 0,
       "usr": "c:@F@foo#",
diff --git a/tests/inheritance/class_inherit.cc b/tests/inheritance/class_inherit.cc
index 64e710cf..bf400b26 100644
--- a/tests/inheritance/class_inherit.cc
+++ b/tests/inheritance/class_inherit.cc
@@ -4,6 +4,7 @@ class Derived : public Parent {};
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@S@Parent",
diff --git a/tests/inheritance/class_inherit_templated_parent.cc b/tests/inheritance/class_inherit_templated_parent.cc
index 9c6759c1..a522040f 100644
--- a/tests/inheritance/class_inherit_templated_parent.cc
+++ b/tests/inheritance/class_inherit_templated_parent.cc
@@ -15,6 +15,7 @@ class Derived : Base1<3>, Base2<Derived>, Derived1<4>, Derived2<Derived> {};
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@ST>1#Ni@Base1",
diff --git a/tests/inheritance/class_multiple_inherit.cc b/tests/inheritance/class_multiple_inherit.cc
index cb4d5e5e..081803f4 100644
--- a/tests/inheritance/class_multiple_inherit.cc
+++ b/tests/inheritance/class_multiple_inherit.cc
@@ -6,6 +6,7 @@ class Derived : public MiddleA, public MiddleB {};
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@S@Root",
diff --git a/tests/inheritance/function_override.cc b/tests/inheritance/function_override.cc
index 7119dc9c..7efce84f 100644
--- a/tests/inheritance/function_override.cc
+++ b/tests/inheritance/function_override.cc
@@ -8,6 +8,7 @@ class Derived : public Root {
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@S@Root",
diff --git a/tests/inheritance/interface_pure_virtual.cc b/tests/inheritance/interface_pure_virtual.cc
index be3f3041..19e692fd 100644
--- a/tests/inheritance/interface_pure_virtual.cc
+++ b/tests/inheritance/interface_pure_virtual.cc
@@ -5,6 +5,7 @@ class IFoo {
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@S@IFoo",
diff --git a/tests/method_declaration.cc b/tests/method_declaration.cc
index 81cbe4b5..ae333d5d 100644
--- a/tests/method_declaration.cc
+++ b/tests/method_declaration.cc
@@ -9,6 +9,7 @@ class Foo {
 
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@S@Foo",
diff --git a/tests/method_definition.cc b/tests/method_definition.cc
index 94fd1daa..138dd6c3 100644
--- a/tests/method_definition.cc
+++ b/tests/method_definition.cc
@@ -7,6 +7,7 @@ void Foo::foo() {}
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@S@Foo",
diff --git a/tests/method_inline_declaration.cc b/tests/method_inline_declaration.cc
index 290c2fb6..14132bba 100644
--- a/tests/method_inline_declaration.cc
+++ b/tests/method_inline_declaration.cc
@@ -5,6 +5,7 @@ class Foo {
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@S@Foo",
diff --git a/tests/multi_file/funky_enum.cc b/tests/multi_file/funky_enum.cc
index e10c8318..a4dde24c 100644
--- a/tests/multi_file/funky_enum.cc
+++ b/tests/multi_file/funky_enum.cc
@@ -8,6 +8,7 @@ enum Foo {
 
 OUTPUT: funky_enum.h
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@E@Foo",
@@ -45,9 +46,9 @@ OUTPUT: funky_enum.h
       "uses": ["6:1-6:2"]
     }]
 }
-
 OUTPUT: funky_enum.cc
 {
+  "last_modification_time": 1,
   "dependencies": ["C:/Users/jacob/Desktop/superindex/indexer/tests/multi_file/funky_enum.h"],
   "types": [{
       "id": 0,
diff --git a/tests/multi_file/impl.cc b/tests/multi_file/impl.cc
index 85e9cd4e..3bd3ed73 100644
--- a/tests/multi_file/impl.cc
+++ b/tests/multi_file/impl.cc
@@ -7,6 +7,7 @@ void Impl() {
 /*
 OUTPUT: header.h
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@S@Base",
@@ -110,6 +111,7 @@ OUTPUT: header.h
 }
 OUTPUT: impl.cc
 {
+  "last_modification_time": 1,
   "dependencies": ["C:/Users/jacob/Desktop/superindex/indexer/tests/multi_file/header.h"],
   "funcs": [{
       "id": 0,
diff --git a/tests/multi_file/simple_impl.cc b/tests/multi_file/simple_impl.cc
index 4250e685..aa456caf 100644
--- a/tests/multi_file/simple_impl.cc
+++ b/tests/multi_file/simple_impl.cc
@@ -7,6 +7,7 @@ void impl() {
 /*
 OUTPUT: simple_header.h
 {
+  "last_modification_time": 1,
   "funcs": [{
       "id": 0,
       "usr": "c:@F@header#",
@@ -17,6 +18,7 @@ OUTPUT: simple_header.h
 }
 OUTPUT: simple_impl.cc
 {
+  "last_modification_time": 1,
   "dependencies": ["C:/Users/jacob/Desktop/superindex/indexer/tests/multi_file/simple_header.h"],
   "funcs": [{
       "id": 0,
diff --git a/tests/multi_file/static.cc b/tests/multi_file/static.cc
index 4073f72c..bdf1f51f 100644
--- a/tests/multi_file/static.cc
+++ b/tests/multi_file/static.cc
@@ -5,6 +5,7 @@ void Buffer::CreateSharedBuffer() {}
 /*
 OUTPUT: static.h
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@S@Buffer",
@@ -26,6 +27,7 @@ OUTPUT: static.h
 }
 OUTPUT: static.cc
 {
+  "last_modification_time": 1,
   "dependencies": ["C:/Users/jacob/Desktop/superindex/indexer/tests/multi_file/static.h"],
   "types": [{
       "id": 0,
diff --git a/tests/namespaces/anonymous_function.cc b/tests/namespaces/anonymous_function.cc
index c20ef5ef..4c5a552c 100644
--- a/tests/namespaces/anonymous_function.cc
+++ b/tests/namespaces/anonymous_function.cc
@@ -5,6 +5,7 @@ void foo();
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "funcs": [{
       "id": 0,
       "usr": "c:anonymous_function.cc@aN@F@foo#",
diff --git a/tests/namespaces/function_declaration.cc b/tests/namespaces/function_declaration.cc
index d7769c64..cfd1a80f 100644
--- a/tests/namespaces/function_declaration.cc
+++ b/tests/namespaces/function_declaration.cc
@@ -5,6 +5,7 @@ void foo(int a, int b);
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "funcs": [{
       "id": 0,
       "usr": "c:@N@hello@F@foo#I#I#",
diff --git a/tests/namespaces/function_definition.cc b/tests/namespaces/function_definition.cc
index fea89dbc..ca66679a 100644
--- a/tests/namespaces/function_definition.cc
+++ b/tests/namespaces/function_definition.cc
@@ -5,6 +5,7 @@ void foo() {}
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "funcs": [{
       "id": 0,
       "usr": "c:@N@hello@F@foo#",
diff --git a/tests/namespaces/method_declaration.cc b/tests/namespaces/method_declaration.cc
index db5560aa..155671df 100644
--- a/tests/namespaces/method_declaration.cc
+++ b/tests/namespaces/method_declaration.cc
@@ -7,6 +7,7 @@ class Foo {
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@N@hello@S@Foo",
diff --git a/tests/namespaces/method_definition.cc b/tests/namespaces/method_definition.cc
index abd93369..7f2711d1 100644
--- a/tests/namespaces/method_definition.cc
+++ b/tests/namespaces/method_definition.cc
@@ -9,6 +9,7 @@ void Foo::foo() {}
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@N@hello@S@Foo",
diff --git a/tests/namespaces/method_inline_declaration.cc b/tests/namespaces/method_inline_declaration.cc
index ab6e5c5b..5c972b7a 100644
--- a/tests/namespaces/method_inline_declaration.cc
+++ b/tests/namespaces/method_inline_declaration.cc
@@ -7,6 +7,7 @@ class Foo {
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@N@hello@S@Foo",
diff --git a/tests/namespaces/namespace_reference.cc b/tests/namespaces/namespace_reference.cc
index 17566a6a..44290cee 100644
--- a/tests/namespaces/namespace_reference.cc
+++ b/tests/namespaces/namespace_reference.cc
@@ -12,6 +12,7 @@ void Runner() {
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "funcs": [{
       "id": 0,
       "usr": "c:@N@ns@F@Accept#I#",
diff --git a/tests/outline/outline.cc b/tests/outline/outline.cc
index c4bf92a8..9e0ed903 100644
--- a/tests/outline/outline.cc
+++ b/tests/outline/outline.cc
@@ -9,6 +9,7 @@ struct MergeableUpdate {
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "dependencies": ["C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/vadefs.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/vcruntime.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/corecrt.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/yvals.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/stdint.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/cstdint", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/corecrt_malloc.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/stddef.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/corecrt_search.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/corecrt_wstdlib.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/stdlib.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/cstdlib", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/ymath.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/float.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/math.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/cmath", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/xtr1common", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/xtgmath.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/errno.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/vcruntime_string.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/corecrt_memcpy_s.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/corecrt_stdio_config.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/corecrt_wconio.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/corecrt_wctype.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/corecrt_wdirect.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/corecrt_wio.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/corecrt_wprocess.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/corecrt_wstdio.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/corecrt_wstring.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/corecrt_wtime.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/sys/types.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/sys/stat.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/wchar.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/cwchar", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/cstddef", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/initializer_list", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/xstddef", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/limits", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/type_traits", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/exception", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/malloc.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/corecrt_terminate.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/eh.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/vcruntime_exception.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/vcruntime_new.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/new", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/stdio.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/cstdio", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/corecrt_memory.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/string.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/cstring", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/vcruntime_new_debug.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/crtdbg.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/iosfwd", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/utility", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/xutility", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/xmemory0", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/xatomic0.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/setjmp.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/mmintrin.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/xmmintrin.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/emmintrin.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/pmmintrin.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/tmmintrin.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/smmintrin.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/nmmintrin.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/wmmintrin.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/immintrin.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/ammintrin.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/intrin.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/xmemory", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/xstring", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/stdexcept", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/vector"],
   "types": [{
       "id": 0,
diff --git a/tests/outline/outline2.cc b/tests/outline/outline2.cc
index 42b49a12..b0062e3a 100644
--- a/tests/outline/outline2.cc
+++ b/tests/outline/outline2.cc
@@ -14,6 +14,7 @@ std::vector<CompilationEntry> LoadCompilationEntriesFromDirectory(const std::str
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "dependencies": ["C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/vadefs.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/vcruntime.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/corecrt.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/yvals.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/math.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/cmath", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/corecrt_malloc.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/stddef.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/corecrt_search.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/corecrt_wstdlib.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/stdlib.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/cstdlib", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/xtr1common", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/xtgmath.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/corecrt_stdio_config.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/corecrt_wstdio.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/stdio.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/cstdio", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/errno.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/vcruntime_string.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/corecrt_memcpy_s.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/corecrt_memory.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/corecrt_wstring.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/string.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/cstring", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/cstddef", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/initializer_list", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/xstddef", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/type_traits", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/exception", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/malloc.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/corecrt_terminate.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/eh.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/vcruntime_exception.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/stdint.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/cstdint", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/ymath.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/float.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/corecrt_wconio.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/corecrt_wctype.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/corecrt_wdirect.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/corecrt_wio.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/corecrt_wprocess.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/corecrt_wtime.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/sys/types.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/sys/stat.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/wchar.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/cwchar", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/limits", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/vcruntime_new.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/new", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/vcruntime_new_debug.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/crtdbg.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/iosfwd", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/utility", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/xutility", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/xmemory0", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/xatomic0.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/setjmp.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/mmintrin.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/xmmintrin.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/emmintrin.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/pmmintrin.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/tmmintrin.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/smmintrin.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/nmmintrin.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/wmmintrin.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/immintrin.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/ammintrin.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/intrin.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/xstring", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/stdexcept", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/vcruntime_typeinfo.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/ctype.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/locale.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/xlocinfo.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/xlocinfo", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/xfacet", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/xlocale", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/system_error", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/xiosbase", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/streambuf", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/xlocnum", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/ios", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/ostream", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/istream", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/string", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/xmemory", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/vector"],
   "types": [{
       "id": 0,
diff --git a/tests/stl.cc b/tests/stl.cc
index b5660582..e458440d 100644
--- a/tests/stl.cc
+++ b/tests/stl.cc
@@ -135,6 +135,7 @@
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "dependencies": ["C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/vadefs.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/vcruntime.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/corecrt.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/assert.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/complex.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/corecrt_wctype.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/ctype.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/errno.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/float.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/fenv.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/stdint.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/inttypes.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/locale.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/math.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/setjmp.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/signal.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/stddef.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/corecrt_stdio_config.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/corecrt_wstdio.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/stdio.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/corecrt_malloc.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/corecrt_search.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/corecrt_wstdlib.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/stdlib.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/vcruntime_string.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/corecrt_memcpy_s.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/corecrt_memory.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/corecrt_wstring.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/string.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/corecrt_wtime.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/time.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/uchar.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/corecrt_wconio.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/corecrt_wdirect.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/corecrt_wio.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/corecrt_wprocess.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/sys/types.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/sys/stat.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/wchar.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/wctype.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/yvals.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/cmath", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/cstdlib", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/xtr1common", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/xtgmath.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/cstdio", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/cstring", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/cstddef", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/initializer_list", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/xstddef", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/type_traits", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/exception", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/malloc.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/corecrt_terminate.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/eh.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/vcruntime_exception.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/cstdint", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/ymath.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/cwchar", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/limits", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/vcruntime_new.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/new", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/vcruntime_new_debug.h", "C:/Program Files (x86)/Windows Kits/10/Include/10.0.14393.0/ucrt/crtdbg.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/iosfwd", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/utility", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/xutility", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/xmemory0", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/xatomic0.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/mmintrin.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/xmmintrin.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/emmintrin.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/pmmintrin.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/tmmintrin.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/smmintrin.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/nmmintrin.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/wmmintrin.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/immintrin.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/ammintrin.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/intrin.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/xstring", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/stdexcept", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/vcruntime_typeinfo.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/xlocinfo.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/xlocinfo", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/xfacet", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/xlocale", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/system_error", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/xiosbase", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/streambuf", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/xlocnum", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/ios", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/ostream", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/istream", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/string", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/xmemory", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/algorithm", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/iterator", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/xtree", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/set", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/fstream", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/memory", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/vector", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/sstream", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/xlocmon", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/ctime", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/xloctime", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/iomanip", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/tuple", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/csignal", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/csetjmp", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/cstdarg", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/typeindex", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/bitset", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/xfunctional", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/functional", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/ratio", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/thr/xthrcommon.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/thr/xtimec.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/chrono", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/scoped_allocator", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/cinttypes", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/cctype", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/cwctype", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/cuchar", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/array", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/deque", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/list", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/forward_list", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/map", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/xhash", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/unordered_set", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/unordered_map", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/stack", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/queue", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/complex", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/xcomplex", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/valarray", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/random", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/numeric", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/cfenv", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/iostream", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/strstream", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/xlocbuf", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/xlocmes", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/locale", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/clocale", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/codecvt", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/regex", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/xatomic.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/atomic", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/xxatomic", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/thr/xtime", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/thr/xthreads.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/thr/xthread", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/thread", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/mutex", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/condition_variable", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/shared_mutex", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/pplinterface.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/ppltaskscheduler.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/pplwin.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/pplcancellation_token.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/ppltasks.h", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/future", "C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/include/filesystem"]
 }
 */
diff --git a/tests/templates/func_specialized_template_param.cc b/tests/templates/func_specialized_template_param.cc
index 42820435..a92570e4 100644
--- a/tests/templates/func_specialized_template_param.cc
+++ b/tests/templates/func_specialized_template_param.cc
@@ -10,6 +10,7 @@ void Foo::Bar(Template<double>&) {}
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@ST>1#T@Template",
diff --git a/tests/templates/implicit_variable_instantiation.cc b/tests/templates/implicit_variable_instantiation.cc
index 0bb93770..fbc6659e 100644
--- a/tests/templates/implicit_variable_instantiation.cc
+++ b/tests/templates/implicit_variable_instantiation.cc
@@ -17,6 +17,7 @@ namespace ns {
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@N@ns@E@VarType",
diff --git a/tests/templates/namespace_template_class_template_func_usage_folded_into_one.cc b/tests/templates/namespace_template_class_template_func_usage_folded_into_one.cc
index 50fdea22..bfeb2686 100644
--- a/tests/templates/namespace_template_class_template_func_usage_folded_into_one.cc
+++ b/tests/templates/namespace_template_class_template_func_usage_folded_into_one.cc
@@ -14,6 +14,7 @@ namespace ns {
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@N@ns@ST>1#T@Foo",
diff --git a/tests/templates/namespace_template_type_usage_folded_into_one.cc b/tests/templates/namespace_template_type_usage_folded_into_one.cc
index eca842f9..c0d878d9 100644
--- a/tests/templates/namespace_template_type_usage_folded_into_one.cc
+++ b/tests/templates/namespace_template_type_usage_folded_into_one.cc
@@ -9,6 +9,7 @@ namespace ns {
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@N@ns@ST>1#T@Foo",
diff --git a/tests/templates/specialized_func_definition.cc b/tests/templates/specialized_func_definition.cc
index 33b34419..ea0ce5ce 100644
--- a/tests/templates/specialized_func_definition.cc
+++ b/tests/templates/specialized_func_definition.cc
@@ -15,6 +15,7 @@ void Template<void>::Foo() {}
 
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@ST>1#T@Template",
diff --git a/tests/templates/template_class_func_usage_folded_into_one.cc b/tests/templates/template_class_func_usage_folded_into_one.cc
index 423c421d..4382dae7 100644
--- a/tests/templates/template_class_func_usage_folded_into_one.cc
+++ b/tests/templates/template_class_func_usage_folded_into_one.cc
@@ -11,6 +11,7 @@ int b = Foo<bool>::foo();
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@ST>1#T@Foo",
diff --git a/tests/templates/template_class_template_func_usage_folded_into_one.cc b/tests/templates/template_class_template_func_usage_folded_into_one.cc
index efea301a..952dac6c 100644
--- a/tests/templates/template_class_template_func_usage_folded_into_one.cc
+++ b/tests/templates/template_class_template_func_usage_folded_into_one.cc
@@ -12,6 +12,7 @@ int b = Foo<bool>::foo<double>();
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@ST>1#T@Foo",
diff --git a/tests/templates/template_class_type_usage_folded_into_one.cc b/tests/templates/template_class_type_usage_folded_into_one.cc
index 52c61e58..b6d917f4 100644
--- a/tests/templates/template_class_type_usage_folded_into_one.cc
+++ b/tests/templates/template_class_type_usage_folded_into_one.cc
@@ -30,6 +30,7 @@ VarDecl b
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@E@A",
diff --git a/tests/templates/template_class_var_usage_folded_into_one.cc b/tests/templates/template_class_var_usage_folded_into_one.cc
index ae224965..5cc1e197 100644
--- a/tests/templates/template_class_var_usage_folded_into_one.cc
+++ b/tests/templates/template_class_var_usage_folded_into_one.cc
@@ -9,6 +9,7 @@ int b = Foo<bool>::var;
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@ST>1#T@Foo",
diff --git a/tests/templates/template_func_usage_folded_into_one.cc b/tests/templates/template_func_usage_folded_into_one.cc
index dad74234..33aebd68 100644
--- a/tests/templates/template_func_usage_folded_into_one.cc
+++ b/tests/templates/template_func_usage_folded_into_one.cc
@@ -12,6 +12,7 @@ int b = foo<bool>();
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "funcs": [{
       "id": 0,
       "usr": "c:template_func_usage_folded_into_one.cc@FT@>1#Tfoo#I#",
diff --git a/tests/templates/template_type_usage_folded_into_one.cc b/tests/templates/template_type_usage_folded_into_one.cc
index 1acc2653..5c487e42 100644
--- a/tests/templates/template_type_usage_folded_into_one.cc
+++ b/tests/templates/template_type_usage_folded_into_one.cc
@@ -7,6 +7,7 @@ Foo<bool> b;
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@ST>1#T@Foo",
diff --git a/tests/templates/template_var_usage_folded_into_one.cc b/tests/templates/template_var_usage_folded_into_one.cc
index a55aa064..1f0900d8 100644
--- a/tests/templates/template_var_usage_folded_into_one.cc
+++ b/tests/templates/template_var_usage_folded_into_one.cc
@@ -30,6 +30,7 @@ UnexposedDecl var
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@E@A",
diff --git a/tests/types/anonymous_struct.cc b/tests/types/anonymous_struct.cc
index b1091372..da9127aa 100644
--- a/tests/types/anonymous_struct.cc
+++ b/tests/types/anonymous_struct.cc
@@ -6,6 +6,7 @@ union vector3 {
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@U@vector3",
diff --git a/tests/unions/union_decl.cc b/tests/unions/union_decl.cc
index f72c3bcd..57a3c169 100644
--- a/tests/unions/union_decl.cc
+++ b/tests/unions/union_decl.cc
@@ -6,6 +6,7 @@ union Foo {
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@U@Foo",
diff --git a/tests/unions/union_usage.cc b/tests/unions/union_usage.cc
index 68f01317..4bbd438c 100644
--- a/tests/unions/union_usage.cc
+++ b/tests/unions/union_usage.cc
@@ -14,6 +14,7 @@ void act(Foo*) {
 
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@U@Foo",
diff --git a/tests/usage/func_called_from_constructor.cc b/tests/usage/func_called_from_constructor.cc
index 4b2aeff3..35625a25 100644
--- a/tests/usage/func_called_from_constructor.cc
+++ b/tests/usage/func_called_from_constructor.cc
@@ -11,6 +11,7 @@ Foo::Foo() {
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@S@Foo",
diff --git a/tests/usage/func_called_from_macro_argument.cc b/tests/usage/func_called_from_macro_argument.cc
index 86d4bfe1..4b2fa095 100644
--- a/tests/usage/func_called_from_macro_argument.cc
+++ b/tests/usage/func_called_from_macro_argument.cc
@@ -9,6 +9,7 @@ void caller() {
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "funcs": [{
       "id": 0,
       "usr": "c:@F@called#b#b#",
diff --git a/tests/usage/func_called_from_template.cc b/tests/usage/func_called_from_template.cc
index 4b34b39a..70909528 100644
--- a/tests/usage/func_called_from_template.cc
+++ b/tests/usage/func_called_from_template.cc
@@ -14,6 +14,7 @@ void foo() {
 // called() is never referenced.
 OUTPUT:
 {
+  "last_modification_time": 1,
   "funcs": [{
       "id": 0,
       "usr": "c:@F@called#",
diff --git a/tests/usage/func_called_implicit_ctor.cc b/tests/usage/func_called_implicit_ctor.cc
index 1ae098ac..c9efa055 100644
--- a/tests/usage/func_called_implicit_ctor.cc
+++ b/tests/usage/func_called_implicit_ctor.cc
@@ -11,6 +11,7 @@ Wrapper caller() {
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@S@Wrapper",
diff --git a/tests/usage/func_usage_addr_func.cc b/tests/usage/func_usage_addr_func.cc
index 0bf2261f..8b9a3cb1 100644
--- a/tests/usage/func_usage_addr_func.cc
+++ b/tests/usage/func_usage_addr_func.cc
@@ -10,6 +10,7 @@ void user() {
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "funcs": [{
       "id": 0,
       "usr": "c:@F@consume#*v#",
diff --git a/tests/usage/func_usage_addr_method.cc b/tests/usage/func_usage_addr_method.cc
index 9ec5b89b..52489c18 100644
--- a/tests/usage/func_usage_addr_method.cc
+++ b/tests/usage/func_usage_addr_method.cc
@@ -10,6 +10,7 @@ void user() {
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@S@Foo",
diff --git a/tests/usage/func_usage_call_func.cc b/tests/usage/func_usage_call_func.cc
index ece26390..b9303154 100644
--- a/tests/usage/func_usage_call_func.cc
+++ b/tests/usage/func_usage_call_func.cc
@@ -6,6 +6,7 @@ void caller() {
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "funcs": [{
       "id": 0,
       "usr": "c:@F@called#",
diff --git a/tests/usage/func_usage_call_method.cc b/tests/usage/func_usage_call_method.cc
index 365f68b7..4358aa41 100644
--- a/tests/usage/func_usage_call_method.cc
+++ b/tests/usage/func_usage_call_method.cc
@@ -10,6 +10,7 @@ void user() {
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@S@Foo",
diff --git a/tests/usage/func_usage_class_inline_var_def.cc b/tests/usage/func_usage_class_inline_var_def.cc
index 460af4b2..65d754ae 100644
--- a/tests/usage/func_usage_class_inline_var_def.cc
+++ b/tests/usage/func_usage_class_inline_var_def.cc
@@ -9,6 +9,7 @@ class Foo {
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@S@Foo",
diff --git a/tests/usage/func_usage_forward_decl_func.cc b/tests/usage/func_usage_forward_decl_func.cc
index 0d37c8bf..e09d1e39 100644
--- a/tests/usage/func_usage_forward_decl_func.cc
+++ b/tests/usage/func_usage_forward_decl_func.cc
@@ -6,6 +6,7 @@ void usage() {
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "funcs": [{
       "id": 0,
       "usr": "c:@F@foo#",
diff --git a/tests/usage/func_usage_forward_decl_method.cc b/tests/usage/func_usage_forward_decl_method.cc
index e93876ba..e413bf9d 100644
--- a/tests/usage/func_usage_forward_decl_method.cc
+++ b/tests/usage/func_usage_forward_decl_method.cc
@@ -9,6 +9,7 @@ void usage() {
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@S@Foo",
diff --git a/tests/usage/func_usage_template_func.cc b/tests/usage/func_usage_template_func.cc
index aecc9fce..979e08a6 100644
--- a/tests/usage/func_usage_template_func.cc
+++ b/tests/usage/func_usage_template_func.cc
@@ -9,6 +9,7 @@ void foo() {
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "funcs": [{
       "id": 0,
       "usr": "c:@FT@>1#Taccept#t0.0#v#",
diff --git a/tests/usage/type_usage_as_template_parameter.cc b/tests/usage/type_usage_as_template_parameter.cc
index 8dbbb0a0..6e947396 100644
--- a/tests/usage/type_usage_as_template_parameter.cc
+++ b/tests/usage/type_usage_as_template_parameter.cc
@@ -13,6 +13,7 @@ unique_ptr<S>* return_type() {
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@ST>1#T@unique_ptr",
diff --git a/tests/usage/type_usage_as_template_parameter_complex.cc b/tests/usage/type_usage_as_template_parameter_complex.cc
index 7fc9420b..e16041c0 100644
--- a/tests/usage/type_usage_as_template_parameter_complex.cc
+++ b/tests/usage/type_usage_as_template_parameter_complex.cc
@@ -81,6 +81,7 @@ unique_ptr<S1, S2>* Foo::foo() { return nullptr; }
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@ST>2#T#T@unique_ptr",
diff --git a/tests/usage/type_usage_as_template_parameter_simple.cc b/tests/usage/type_usage_as_template_parameter_simple.cc
index 18c437f0..00bbe618 100644
--- a/tests/usage/type_usage_as_template_parameter_simple.cc
+++ b/tests/usage/type_usage_as_template_parameter_simple.cc
@@ -8,6 +8,7 @@ static unique_ptr<S> foo;
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@ST>1#T@unique_ptr",
diff --git a/tests/usage/type_usage_declare_extern.cc b/tests/usage/type_usage_declare_extern.cc
index 3912024d..d8868925 100644
--- a/tests/usage/type_usage_declare_extern.cc
+++ b/tests/usage/type_usage_declare_extern.cc
@@ -4,6 +4,7 @@ extern T t;
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@S@T",
diff --git a/tests/usage/type_usage_declare_field.cc b/tests/usage/type_usage_declare_field.cc
index 5711f4b8..4fae5340 100644
--- a/tests/usage/type_usage_declare_field.cc
+++ b/tests/usage/type_usage_declare_field.cc
@@ -9,6 +9,7 @@ struct Foo {
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@S@ForwardType",
diff --git a/tests/usage/type_usage_declare_local.cc b/tests/usage/type_usage_declare_local.cc
index 663df5bf..3ecff52f 100644
--- a/tests/usage/type_usage_declare_local.cc
+++ b/tests/usage/type_usage_declare_local.cc
@@ -9,6 +9,7 @@ void Foo() {
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@S@ForwardType",
diff --git a/tests/usage/type_usage_declare_param.cc b/tests/usage/type_usage_declare_param.cc
index 36919f0c..ee6fcd25 100644
--- a/tests/usage/type_usage_declare_param.cc
+++ b/tests/usage/type_usage_declare_param.cc
@@ -6,6 +6,7 @@ void foo(ForwardType* f, ImplementedType a) {}
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@S@ForwardType",
diff --git a/tests/usage/type_usage_declare_param_prototype.cc b/tests/usage/type_usage_declare_param_prototype.cc
index 3a3d473d..e1ce3747 100644
--- a/tests/usage/type_usage_declare_param_prototype.cc
+++ b/tests/usage/type_usage_declare_param_prototype.cc
@@ -11,6 +11,7 @@ void foo(Foo* f, Foo*) {}
 
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@S@Foo",
diff --git a/tests/usage/type_usage_declare_param_unnamed.cc b/tests/usage/type_usage_declare_param_unnamed.cc
index 26a4cd6c..1ca3aa3a 100644
--- a/tests/usage/type_usage_declare_param_unnamed.cc
+++ b/tests/usage/type_usage_declare_param_unnamed.cc
@@ -3,6 +3,7 @@ void foo(ForwardType*) {}
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@S@ForwardType",
diff --git a/tests/usage/type_usage_declare_qualifiers.cc b/tests/usage/type_usage_declare_qualifiers.cc
index d1c5eb87..3771f91d 100644
--- a/tests/usage/type_usage_declare_qualifiers.cc
+++ b/tests/usage/type_usage_declare_qualifiers.cc
@@ -9,6 +9,7 @@ void foo(Type& a0, const Type& a1) {
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@S@Type",
diff --git a/tests/usage/type_usage_declare_static.cc b/tests/usage/type_usage_declare_static.cc
index d96e1372..242c1715 100644
--- a/tests/usage/type_usage_declare_static.cc
+++ b/tests/usage/type_usage_declare_static.cc
@@ -3,6 +3,7 @@ static Type t;
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@S@Type",
diff --git a/tests/usage/type_usage_on_return_type.cc b/tests/usage/type_usage_on_return_type.cc
index 875ea4f6..d330c368 100644
--- a/tests/usage/type_usage_on_return_type.cc
+++ b/tests/usage/type_usage_on_return_type.cc
@@ -20,6 +20,7 @@ static Type* bar() {}
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@S@Type",
diff --git a/tests/usage/type_usage_typedef_and_using.cc b/tests/usage/type_usage_typedef_and_using.cc
index 3974157f..58d80463 100644
--- a/tests/usage/type_usage_typedef_and_using.cc
+++ b/tests/usage/type_usage_typedef_and_using.cc
@@ -12,6 +12,7 @@ void accept3(Foo3*) {}
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@S@Foo",
diff --git a/tests/usage/type_usage_typedef_and_using_template.cc b/tests/usage/type_usage_typedef_and_using_template.cc
index 29614e1c..d2e09be1 100644
--- a/tests/usage/type_usage_typedef_and_using_template.cc
+++ b/tests/usage/type_usage_typedef_and_using_template.cc
@@ -7,6 +7,7 @@ typedef Foo<Foo1> Foo2;
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@ST>1#T@Foo",
diff --git a/tests/usage/type_usage_various.cc b/tests/usage/type_usage_various.cc
index f2c52f80..b3bd48f0 100644
--- a/tests/usage/type_usage_various.cc
+++ b/tests/usage/type_usage_various.cc
@@ -12,6 +12,7 @@ extern Foo foo;
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@S@Foo",
diff --git a/tests/usage/usage_inside_of_call.cc b/tests/usage/usage_inside_of_call.cc
index 3feb1714..2b44ce6a 100644
--- a/tests/usage/usage_inside_of_call.cc
+++ b/tests/usage/usage_inside_of_call.cc
@@ -17,6 +17,7 @@ void foo() {
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@S@Foo",
diff --git a/tests/usage/usage_inside_of_call_simple.cc b/tests/usage/usage_inside_of_call_simple.cc
index 8bb1470b..6329fab8 100644
--- a/tests/usage/usage_inside_of_call_simple.cc
+++ b/tests/usage/usage_inside_of_call_simple.cc
@@ -9,6 +9,7 @@ void foo() {
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "funcs": [{
       "id": 0,
       "usr": "c:@F@called#I#",
diff --git a/tests/usage/var_usage_call_function.cc b/tests/usage/var_usage_call_function.cc
index 2d411d1d..e06256bc 100644
--- a/tests/usage/var_usage_call_function.cc
+++ b/tests/usage/var_usage_call_function.cc
@@ -10,6 +10,7 @@ void caller() {
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "funcs": [{
       "id": 0,
       "usr": "c:@F@called#",
diff --git a/tests/usage/var_usage_class_member.cc b/tests/usage/var_usage_class_member.cc
index 665f5b9b..b83e3c40 100644
--- a/tests/usage/var_usage_class_member.cc
+++ b/tests/usage/var_usage_class_member.cc
@@ -20,6 +20,7 @@ void foo() {
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@S@Foo",
diff --git a/tests/usage/var_usage_class_member_static.cc b/tests/usage/var_usage_class_member_static.cc
index b0f35acd..5fa635ec 100644
--- a/tests/usage/var_usage_class_member_static.cc
+++ b/tests/usage/var_usage_class_member_static.cc
@@ -11,6 +11,7 @@ void foo() {
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@S@Foo",
diff --git a/tests/usage/var_usage_cstyle_cast.cc b/tests/usage/var_usage_cstyle_cast.cc
index 02db8dfc..11366b82 100644
--- a/tests/usage/var_usage_cstyle_cast.cc
+++ b/tests/usage/var_usage_cstyle_cast.cc
@@ -10,6 +10,7 @@ const VarType Holder::static_var;
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@E@VarType",
diff --git a/tests/usage/var_usage_extern.cc b/tests/usage/var_usage_extern.cc
index 2095d452..a952b359 100644
--- a/tests/usage/var_usage_extern.cc
+++ b/tests/usage/var_usage_extern.cc
@@ -6,6 +6,7 @@ void foo() {
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "funcs": [{
       "id": 0,
       "usr": "c:@F@foo#",
diff --git a/tests/usage/var_usage_func_parameter.cc b/tests/usage/var_usage_func_parameter.cc
index 3f8be1b9..c6843e87 100644
--- a/tests/usage/var_usage_func_parameter.cc
+++ b/tests/usage/var_usage_func_parameter.cc
@@ -4,6 +4,7 @@ void foo(int a) {
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "funcs": [{
       "id": 0,
       "usr": "c:@F@foo#I#",
diff --git a/tests/usage/var_usage_local.cc b/tests/usage/var_usage_local.cc
index 1654fc8a..1ee1a465 100644
--- a/tests/usage/var_usage_local.cc
+++ b/tests/usage/var_usage_local.cc
@@ -5,6 +5,7 @@ void foo() {
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "funcs": [{
       "id": 0,
       "usr": "c:@F@foo#",
diff --git a/tests/usage/var_usage_shadowed_local.cc b/tests/usage/var_usage_shadowed_local.cc
index cdb4a511..f18f380a 100644
--- a/tests/usage/var_usage_shadowed_local.cc
+++ b/tests/usage/var_usage_shadowed_local.cc
@@ -10,6 +10,7 @@ void foo() {
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "funcs": [{
       "id": 0,
       "usr": "c:@F@foo#",
diff --git a/tests/usage/var_usage_shadowed_parameter.cc b/tests/usage/var_usage_shadowed_parameter.cc
index 174a652c..f1abf334 100644
--- a/tests/usage/var_usage_shadowed_parameter.cc
+++ b/tests/usage/var_usage_shadowed_parameter.cc
@@ -10,6 +10,7 @@ void foo(int a) {
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "funcs": [{
       "id": 0,
       "usr": "c:@F@foo#I#",
diff --git a/tests/usage/var_usage_static.cc b/tests/usage/var_usage_static.cc
index ae18e5aa..c2521f5b 100644
--- a/tests/usage/var_usage_static.cc
+++ b/tests/usage/var_usage_static.cc
@@ -7,6 +7,7 @@ void foo() {
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "funcs": [{
       "id": 0,
       "usr": "c:@F@foo#",
diff --git a/tests/vars/class_member.cc b/tests/vars/class_member.cc
index e04b7899..0e2ecc64 100644
--- a/tests/vars/class_member.cc
+++ b/tests/vars/class_member.cc
@@ -4,6 +4,7 @@ class Foo {
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@S@Foo",
diff --git a/tests/vars/class_static_member.cc b/tests/vars/class_static_member.cc
index a0e724d7..895a4dae 100644
--- a/tests/vars/class_static_member.cc
+++ b/tests/vars/class_static_member.cc
@@ -6,6 +6,7 @@ Foo* Foo::member = nullptr;
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@S@Foo",
diff --git a/tests/vars/class_static_member_decl_only.cc b/tests/vars/class_static_member_decl_only.cc
index e2dc728c..f767b750 100644
--- a/tests/vars/class_static_member_decl_only.cc
+++ b/tests/vars/class_static_member_decl_only.cc
@@ -4,6 +4,7 @@ class Foo {
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@S@Foo",
diff --git a/tests/vars/function_local.cc b/tests/vars/function_local.cc
index ed8e1f6e..0910506e 100644
--- a/tests/vars/function_local.cc
+++ b/tests/vars/function_local.cc
@@ -7,6 +7,7 @@ void foo() {
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@S@Foo",
diff --git a/tests/vars/function_param.cc b/tests/vars/function_param.cc
index 4d2caa23..a34ee18a 100644
--- a/tests/vars/function_param.cc
+++ b/tests/vars/function_param.cc
@@ -5,6 +5,7 @@ void foo(Foo* p0, Foo* p1) {}
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "types": [{
       "id": 0,
       "usr": "c:@S@Foo",
diff --git a/tests/vars/function_param_unnamed.cc b/tests/vars/function_param_unnamed.cc
index 228e2617..3938bf07 100644
--- a/tests/vars/function_param_unnamed.cc
+++ b/tests/vars/function_param_unnamed.cc
@@ -2,6 +2,7 @@ void foo(int, int) {}
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "funcs": [{
       "id": 0,
       "usr": "c:@F@foo#I#I#",
diff --git a/tests/vars/function_shadow_local.cc b/tests/vars/function_shadow_local.cc
index a28fdbfe..7d6bb452 100644
--- a/tests/vars/function_shadow_local.cc
+++ b/tests/vars/function_shadow_local.cc
@@ -10,6 +10,7 @@ void foo() {
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "funcs": [{
       "id": 0,
       "usr": "c:@F@foo#",
diff --git a/tests/vars/function_shadow_param.cc b/tests/vars/function_shadow_param.cc
index 6ea78ccd..445417b9 100644
--- a/tests/vars/function_shadow_param.cc
+++ b/tests/vars/function_shadow_param.cc
@@ -4,6 +4,7 @@ void foo(int p) {
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "funcs": [{
       "id": 0,
       "usr": "c:@F@foo#I#",
diff --git a/tests/vars/global_variable.cc b/tests/vars/global_variable.cc
index 9c01be9d..d2444fa5 100644
--- a/tests/vars/global_variable.cc
+++ b/tests/vars/global_variable.cc
@@ -2,6 +2,7 @@ static int global = 0;
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "vars": [{
       "id": 0,
       "usr": "c:global_variable.cc@global",
diff --git a/tests/vars/global_variable_decl_only.cc b/tests/vars/global_variable_decl_only.cc
index f66005c2..c35696dc 100644
--- a/tests/vars/global_variable_decl_only.cc
+++ b/tests/vars/global_variable_decl_only.cc
@@ -2,6 +2,7 @@ extern int global;
 /*
 OUTPUT:
 {
+  "last_modification_time": 1,
   "vars": [{
       "id": 0,
       "usr": "c:@global",