doc: mention handling of {0} in -Wmissing-field-initializers (PR 71250)

	PR other/71250
	* doc/invoke.texi (-Wmissing-field-initializers): Mention that warning
	is suppressed for '{ 0 }' in C.

From-SVN: r247018

gcc/ChangeLog

+2017-04-20  Alexander Monakov  <amonakov@ispras.ru>
+
+	PR other/71250
+	* doc/invoke.texi (-Wmissing-field-initializers): Mention that warning
+	is suppressed for '{ 0 }' in C.
+
 2017-04-20  Jakub Jelinek  <jakub@redhat.com>
 
 	* BASE-VER: Set to 8.0.0.

gcc/doc/invoke.texi

@@ -6220,7 +6220,15 @@ struct s @{ int f, g, h; @};
 struct s x = @{ .f = 3, .g = 4 @};
 @end smallexample
 
-In C++ this option does not warn either about the empty @{ @}
+In C this option does not warn about the universal zero initializer
+@samp{@{ 0 @}}:
+
+@smallexample
+struct s @{ int f, g, h; @};
+struct s x = @{ 0 @};
+@end smallexample
+
+Likewise, in C++ this option does not warn about the empty @{ @}
 initializer, for example:
 
 @smallexample