Index: gcc/c-family/c.opt
===================================================================
--- gcc/c-family/c.opt	(revision 187437)
+++ gcc/c-family/c.opt	(working copy)
@@ -302,11 +302,11 @@ Warn about casts which discard qualifier
 Wchar-subscripts
 C ObjC C++ ObjC++ Var(warn_char_subscripts) Warning
 Warn about subscripts whose type is \"char\"
 
 Wclobbered
-C ObjC C++ ObjC++ Var(warn_clobbered) Init(-1) Warning
+C ObjC C++ ObjC++ Var(warn_clobbered) Warning EnabledBy(Wextra)
 Warn about variables that might be changed by \"longjmp\" or \"vfork\"
 
 Wcomment
 C ObjC C++ ObjC++ Warning
 Warn about possibly nested block comments, and C++ comments spanning more than one physical line
@@ -350,11 +350,11 @@ Warn about compile-time integer division
 Weffc++
 C++ ObjC++ Var(warn_ecpp) Warning
 Warn about violations of Effective C++ style rules
 
 Wempty-body
-C ObjC C++ ObjC++ Var(warn_empty_body) Init(-1) Warning
+C ObjC C++ ObjC++ Var(warn_empty_body) Warning EnabledBy(Wextra)
 Warn about an empty body in an if or else statement
 
 Wendif-labels
 C ObjC C++ ObjC++ Warning
 Warn about stray tokens after #elif and #endif
@@ -405,11 +405,11 @@ Warn about zero-length formats
 
 Wformat=
 C ObjC C++ ObjC++ Joined Warning
 
 Wignored-qualifiers
-C C++ Var(warn_ignored_qualifiers) Init(-1) Warning
+C C++ Var(warn_ignored_qualifiers) Warning EnabledBy(Wextra)
 Warn whenever type qualifiers are ignored.
 
 Winit-self
 C ObjC C++ ObjC++ Var(warn_init_self) Warning
 Warn about variables which are initialized to themselves
@@ -472,11 +472,11 @@ Warn about possibly missing braces aroun
 Wmissing-declarations
 C ObjC C++ ObjC++ Var(warn_missing_declarations) Warning
 Warn about global functions without previous declarations
 
 Wmissing-field-initializers
-C ObjC C++ ObjC++ Var(warn_missing_field_initializers) Init(-1) Warning
+C ObjC C++ ObjC++ Var(warn_missing_field_initializers) Warning EnabledBy(Wextra)
 Warn about missing fields in struct initializers
 
 Wsuggest-attribute=format
 C ObjC C++ ObjC++ Var(warn_suggest_attribute_format) Warning
 Warn about functions which might be candidates for format attributes
@@ -488,11 +488,11 @@ C ObjC C++ ObjC++ Alias(Wsuggest-attribu
 Wmissing-include-dirs
 C ObjC C++ ObjC++ Warning
 Warn about user-specified include directories that do not exist
 
 Wmissing-parameter-type
-C ObjC Var(warn_missing_parameter_type) Init(-1) Warning
+C ObjC Var(warn_missing_parameter_type) Warning EnabledBy(Wextra)
 Warn about function parameters declared without a type specifier in K&R-style functions
 
 Wmissing-prototypes
 C ObjC Var(warn_missing_prototypes) Warning
 Warn about global functions without prototypes
@@ -536,11 +536,11 @@ C ObjC C++ ObjC++ Joined Warning
 Wold-style-cast
 C++ ObjC++ Var(warn_old_style_cast) Warning
 Warn if a C-style cast is used in a program
 
 Wold-style-declaration
-C ObjC Var(warn_old_style_declaration) Init(-1) Warning
+C ObjC Var(warn_old_style_declaration) Warning EnabledBy(Wextra)
 Warn for obsolescent usage in a declaration
 
 Wold-style-definition
 C ObjC Var(warn_old_style_definition) Warning
 Warn if an old-style parameter definition is used
@@ -552,11 +552,11 @@ Warn if a string is longer than the maxi
 Woverloaded-virtual
 C++ ObjC++ Var(warn_overloaded_virtual) Warning
 Warn about overloaded virtual function names
 
 Woverride-init
-C ObjC Var(warn_override_init) Init(-1) Warning
+C ObjC Var(warn_override_init) Warning EnabledBy(Wextra)
 Warn about overriding initializers without side effects
 
 Wpacked-bitfield-compat
 C ObjC C++ ObjC++ Var(warn_packed_bitfield_compat) Init(-1) Warning
 Warn about packed bit-fields whose offset changed in GCC 4.4
Index: gcc/c-family/c-opts.c
===================================================================
--- gcc/c-family/c-opts.c	(revision 187437)
+++ gcc/c-family/c-opts.c	(working copy)
@@ -910,28 +910,14 @@ c_common_post_options (const char **pfil
   if (flag_objc_exceptions && !flag_objc_sjlj_exceptions)
     flag_exceptions = 1;
 
   /* -Wextra implies the following flags
      unless explicitly overridden.  */
-  if (warn_type_limits == -1)
-    warn_type_limits = extra_warnings;
-  if (warn_clobbered == -1)
-    warn_clobbered = extra_warnings;
-  if (warn_empty_body == -1)
-    warn_empty_body = extra_warnings;
+
+  /* Wsign-compare is also enabled by -Wall in C++. */
   if (warn_sign_compare == -1)
     warn_sign_compare = extra_warnings;
-  if (warn_missing_field_initializers == -1)
-    warn_missing_field_initializers = extra_warnings;
-  if (warn_missing_parameter_type == -1)
-    warn_missing_parameter_type = extra_warnings;
-  if (warn_old_style_declaration == -1)
-    warn_old_style_declaration = extra_warnings;
-  if (warn_override_init == -1)
-    warn_override_init = extra_warnings;
-  if (warn_ignored_qualifiers == -1)
-    warn_ignored_qualifiers = extra_warnings;
 
   /* -Wpointer-sign is disabled by default, but it is enabled if any
      of -Wall or -Wpedantic are given.  */
   if (warn_pointer_sign == -1)
     warn_pointer_sign = 0;
Index: gcc/common.opt
===================================================================
--- gcc/common.opt	(revision 187437)
+++ gcc/common.opt	(working copy)
@@ -644,11 +644,11 @@ Do not suppress warnings from system hea
 Wtrampolines
 Common Var(warn_trampolines) Warning
 Warn whenever a trampoline is generated
 
 Wtype-limits
-Common Var(warn_type_limits) Init(-1) Warning
+Common Var(warn_type_limits) Warning EnabledBy(Wextra)
 Warn if a comparison is always true or always false due to the limited range of the data type
 
 Wuninitialized
 Common Var(warn_uninitialized) Warning EnabledBy(Wextra)
 Warn about uninitialized automatic variables