diff --git a/gcc/c-family/c.opt b/gcc/c-family/c.opt
index cead1995561..0930a3c0422 100644
--- a/gcc/c-family/c.opt
+++ b/gcc/c-family/c.opt
@@ -1488,6 +1488,10 @@ Wsubobject-linkage
 C++ ObjC++ Var(warn_subobject_linkage) Warning Init(1)
 Warn if a class type has a base or a field whose type uses the anonymous namespace or depends on a type with no linkage.
 
+Welaborated-enum-base
+C++ ObjC++ Var(warn_elaborated_enum_base) Warning Init(1)
+Warn if an additional enum-base is used in an elaborated-type-specifier.
+
 Wduplicate-decl-specifier
 C ObjC Var(warn_duplicate_decl_specifier) Warning LangEnabledBy(C ObjC,Wall)
 Warn when a declaration has duplicate const, volatile, restrict or _Atomic specifier.
diff --git a/gcc/cp/parser.cc b/gcc/cp/parser.cc
index d77fbd20e56..4dd290717de 100644
--- a/gcc/cp/parser.cc
+++ b/gcc/cp/parser.cc
@@ -21024,11 +21024,13 @@ cp_parser_enum_specifier (cp_parser* parser)
 
   /* Check for the `:' that denotes a specified underlying type in C++0x.
      Note that a ':' could also indicate a bitfield width, however.  */
+  location_t colon_loc = UNKNOWN_LOCATION;
   if (cp_lexer_next_token_is (parser->lexer, CPP_COLON))
     {
       cp_decl_specifier_seq type_specifiers;
 
       /* Consume the `:'.  */
+      colon_loc = cp_lexer_peek_token (parser->lexer)->location;
       cp_lexer_consume_token (parser->lexer);
 
       auto tdf
@@ -21077,10 +21079,13 @@ cp_parser_enum_specifier (cp_parser* parser)
 	  && cp_lexer_next_token_is_not (parser->lexer, CPP_SEMICOLON))
 	{
 	  if (has_underlying_type)
-	    cp_parser_commit_to_tentative_parse (parser);
-	  cp_parser_error (parser, "expected %<;%> or %<{%>");
-	  if (has_underlying_type)
-	    return error_mark_node;
+	    pedwarn (colon_loc,
+		     OPT_Welaborated_enum_base,
+		     "declaration of enumeration with "
+		     "fixed underlying type and no enumerator list is "
+		     "only permitted as a standalone declaration");
+	  else
+	    cp_parser_error (parser, "expected %<;%> or %<{%>");
 	}
     }
 
diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi
index 6d08229ce40..8ee5ba15709 100644
--- a/gcc/doc/invoke.texi
+++ b/gcc/doc/invoke.texi
@@ -254,7 +254,8 @@ in the following sections.
 -Wdelete-non-virtual-dtor  -Wno-deprecated-array-compare
 -Wdeprecated-copy -Wdeprecated-copy-dtor
 -Wno-deprecated-enum-enum-conversion -Wno-deprecated-enum-float-conversion
--Weffc++  -Wno-exceptions -Wextra-semi  -Wno-inaccessible-base
+-Weffc++ -Wno-elaborated-enum-base
+-Wno-exceptions -Wextra-semi  -Wno-inaccessible-base
 -Wno-inherited-variadic-ctor  -Wno-init-list-lifetime
 -Winvalid-constexpr -Winvalid-imported-macros
 -Wno-invalid-offsetof  -Wno-literal-suffix
@@ -3846,6 +3847,15 @@ bool b = e <= 3.7;
 @option{-std=c++20}.  In pre-C++20 dialects, this warning can be enabled
 by @option{-Wenum-conversion}.
 
+@opindex Welaborated-enum-base
+@opindex Wno-elaborated-enum-base
+@item -Wno-elaborated-enum-base
+For C++11 and above, warn if an (invalid) additional enum-base is used
+in an elaborated-type-specifier.  That is, if an enum with given
+underlying type and no enumerator list is used in a declaration other
+than just a standalone declaration of the enum.  Enabled by default.  This
+warning is upgraded to an error with -pedantic-errors.
+
 @opindex Winit-list-lifetime
 @opindex Wno-init-list-lifetime
 @item -Wno-init-list-lifetime @r{(C++ and Objective-C++ only)}
@@ -6055,6 +6065,7 @@ errors by @option{-pedantic-errors}.  For instance:
 -Wchanges-meaning @r{(C++)}
 -Wcomma-subscript @r{(C++23 or later)}
 -Wdeclaration-after-statement @r{(C90 or earlier)}
+-Welaborated-enum-base @r{(C++11 or later)}
 -Wimplicit-int @r{(C99 or later)}
 -Wimplicit-function-declaration @r{(C99 or later)}
 -Wincompatible-pointer-types
diff --git a/gcc/testsuite/g++.dg/cpp0x/elab-enum-base.C b/gcc/testsuite/g++.dg/cpp0x/elab-enum-base.C
new file mode 100644
index 00000000000..57141f013bd
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp0x/elab-enum-base.C
@@ -0,0 +1,7 @@
+// { dg-do compile { target c++11 } }
+// { dg-options "" }
+// Empty dg-options to override -pedantic-errors.
+
+typedef long CFIndex;
+typedef enum CFComparisonResult : CFIndex CFComparisonResult;
+// { dg-warning "declaration of enumeration with fixed underlying type" "" { target *-*-* } .-1 }
diff --git a/gcc/testsuite/g++.dg/cpp0x/enum40.C b/gcc/testsuite/g++.dg/cpp0x/enum40.C
index cfdf2a4a18a..d3ffeb62d70 100644
--- a/gcc/testsuite/g++.dg/cpp0x/enum40.C
+++ b/gcc/testsuite/g++.dg/cpp0x/enum40.C
@@ -4,23 +4,25 @@
 void
 foo ()
 {
-  enum : int a alignas;		// { dg-error "expected" }
+  enum : int a alignas;		// { dg-error "declaration of enum" }
+  // { dg-error {expected '\(' before ';'} "" { target *-*-* } .-1 }
 }
 
 void
 bar ()
 {
-  enum : int a;			// { dg-error "expected" }
+  enum : int a;			// { dg-error "declaration of enum" }
 }
 
 void
 baz ()
 {
-  enum class a : int b alignas;	// { dg-error "expected" }
+  enum class a : int b alignas;	// { dg-error "declaration of enum" }
+  // { dg-error {expected '\(' before ';'} "" { target *-*-* } .-1 }
 }
 
 void
 qux ()
 {
-  enum class a : int b;		// { dg-error "expected" }
+  enum class a : int b;		// { dg-error "declaration of enum" }
 }
diff --git a/gcc/testsuite/g++.dg/cpp0x/forw_enum6.C b/gcc/testsuite/g++.dg/cpp0x/forw_enum6.C
index 01bf563bcdd..8ad3f733292 100644
--- a/gcc/testsuite/g++.dg/cpp0x/forw_enum6.C
+++ b/gcc/testsuite/g++.dg/cpp0x/forw_enum6.C
@@ -23,7 +23,7 @@ enum class E7 : int; //ok
 
 enum class E3 e3; // { dg-error "scoped enum must not use" }
 enum struct E3 e4; // { dg-error "scoped enum must not use" }
-enum E5 : int e5; // { dg-error "expected|invalid type" }
+enum E5 : int e5; // { dg-error "declaration of enumeration with fixed underlying type|invalid type" }
 
 enum E6 : int { a, b, c }; // { dg-message "previous definition" }
 enum E6 : int { a, b, c }; // { dg-error "multiple definition" }