Index: docs/ReleaseNotes.rst
===================================================================
--- docs/ReleaseNotes.rst
+++ docs/ReleaseNotes.rst
@@ -50,6 +50,28 @@
 Improvements to Clang's diagnostics
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
+- ``-Wextra-semi-pedantic`` is a new diagnostic, which is, much like
+  ``-Wextra-semi``, diagnoses extra semicolons. This new diagnostic
+  fires on all *unnecessary* null statements (expression statements without
+  an expression), unless: the semi directly follows a macro that was expanded
+  to nothing; the semi is within the macro itself (both macros from system
+  headers, and normal macros).
+
+  .. code-block:: c++
+
+      #define MACRO(x) int x;
+
+      void test() {
+        ; // <- warning: ';' with no preceding expression is a null statement
+
+        while (true)
+          ; // OK, it is needed.
+
+        MACRO(v0;) // Extra semi, but within macro, so ignored.
+
+        MACRO(v1); // <- warning: ';' with no preceding expression is a null statement
+      }
+
 
 Non-comprehensive list of changes in this release
 -------------------------------------------------
Index: include/clang/Basic/DiagnosticGroups.td
===================================================================
--- include/clang/Basic/DiagnosticGroups.td
+++ include/clang/Basic/DiagnosticGroups.td
@@ -160,8 +160,10 @@
 def ExtraTokens : DiagGroup<"extra-tokens">;
 def CXX98CompatExtraSemi : DiagGroup<"c++98-compat-extra-semi">;
 def CXX11ExtraSemi : DiagGroup<"c++11-extra-semi">;
+def ExtraSemiPedantic : DiagGroup<"extra-semi-pedantic">;
 def ExtraSemi : DiagGroup<"extra-semi", [CXX98CompatExtraSemi,
-                                         CXX11ExtraSemi]>;
+                                         CXX11ExtraSemi,
+                                         ExtraSemiPedantic]>;
 
 def GNUFlexibleArrayInitializer : DiagGroup<"gnu-flexible-array-initializer">;
 def GNUFlexibleArrayUnionMember : DiagGroup<"gnu-flexible-array-union-member">;
Index: include/clang/Basic/DiagnosticParseKinds.td
===================================================================
--- include/clang/Basic/DiagnosticParseKinds.td
+++ include/clang/Basic/DiagnosticParseKinds.td
@@ -53,6 +53,9 @@
 def warn_extra_semi_after_mem_fn_def : Warning<
   "extra ';' after member function definition">,
   InGroup<ExtraSemi>, DefaultIgnore;
+def warn_null_statement : Warning<
+  "';' with no preceding expression is a null statement">,
+  InGroup<ExtraSemiPedantic>, DefaultIgnore;
 
 def ext_thread_before : Extension<"'__thread' before '%0'">;
 def ext_keyword_as_ident : ExtWarn<
Index: lib/Parse/ParseStmt.cpp
===================================================================
--- lib/Parse/ParseStmt.cpp
+++ lib/Parse/ParseStmt.cpp
@@ -233,7 +233,13 @@
     return ParseCompoundStatement();
   case tok::semi: {                 // C99 6.8.3p3: expression[opt] ';'
     bool HasLeadingEmptyMacro = Tok.hasLeadingEmptyMacro();
-    return Actions.ActOnNullStmt(ConsumeToken(), HasLeadingEmptyMacro);
+    SourceLocation SemiLocation = ConsumeToken();
+    if (!HasLeadingEmptyMacro && getCurScope()->isCompoundStmtScope() &&
+        !SemiLocation.isMacroID()) {
+      Diag(SemiLocation, diag::warn_null_statement)
+          << FixItHint::CreateRemoval(SemiLocation);
+    }
+    return Actions.ActOnNullStmt(SemiLocation, HasLeadingEmptyMacro);
   }
 
   case tok::kw_if:                  // C99 6.8.4.1: if-statement
Index: test/Parser/extra-semi-resulting-in-nullstmt.cpp
===================================================================
--- /dev/null
+++ test/Parser/extra-semi-resulting-in-nullstmt.cpp
@@ -0,0 +1,62 @@
+// RUN: %clang_cc1 -fsyntax-only -Wextra-semi-pedantic -verify %s
+// RUN: %clang_cc1 -fsyntax-only -Wextra-semi-pedantic -std=c++17 -verify %s
+// RUN: cp %s %t
+// RUN: %clang_cc1 -x c++ -Wextra-semi-pedantic -fixit %t
+// RUN: %clang_cc1 -x c++ -Wextra-semi-pedantic -Werror %t
+
+#define GOODMACRO(varname) int varname
+#define BETTERMACRO(varname) GOODMACRO(varname);
+#define NULLMACRO(varname)
+
+void test() {
+  ; // expected-warning {{';' with no preceding expression is a null statement}}
+  ; // expected-warning {{';' with no preceding expression is a null statement}}
+
+  // clang-format: off
+  ;; // expected-warning 2 {{';' with no preceding expression is a null statement}}
+  // clang-format: on
+
+  {}; // expected-warning {{';' with no preceding expression is a null statement}}
+
+  {
+    ; // expected-warning {{';' with no preceding expression is a null statement}}
+  }
+
+  if (true) {
+    ; // expected-warning {{';' with no preceding expression is a null statement}}
+  }
+
+  GOODMACRO(v0); // OK
+
+  GOODMACRO(v1;) // OK
+
+  BETTERMACRO(v2) // OK
+
+  BETTERMACRO(v3;) // Extra ';', but within macro expansion, so ignored.
+
+  BETTERMACRO(v4); // expected-warning {{';' with no preceding expression is a null statement}}
+
+  BETTERMACRO(v5;); // expected-warning {{';' with no preceding expression is a null statement}}
+
+  NULLMACRO(v6) // OK
+
+  NULLMACRO(v7); // OK. This could be either GOODMACRO() or BETTERMACRO() situation, so we can't know we can drop it.
+
+  if (true)
+    ; // OK
+
+  while (true)
+    ; // OK
+
+  do
+    ; // OK
+  while (true);
+
+  for (;;) // OK
+    ;      // OK
+
+#if __cplusplus >= 201703L
+  if (; true) // OK
+    ;         // OK
+#endif
+}