* cppexp.c (parse_defined): Mark macro used.

	* cpphash.h (struct cpp_macro): New member "used".
	(_cpp_mark_macro_used, _cpp_warn_if_unused_macro): New.
	(struct cpp_reader): New member.
	* cppinit.c (cpp_finish_options): Set first_unused_line.
	(cpp_finish): Warn of unused macros if requested.
	(OPT_TABLE): New switches.
	(cpp_handle_option): Handle them.
	* cpplib.c (do_undef): Warn if macro unused.
	(do_ifdef, do_ifndef): Mark macro used.
	* cpplib.h (struct cpp_options): New member.
	* cppmacro.c (_cpp_warn_if_unused_macro): New.
	(enter_macro_context): Mark macro used.
	(_cpp_create_definition): Mark macro unused; warn if unused
	when redefined.
	* cpptrad.c (scan_out_logcial_line, push_replacement_text):
	Mark macros used.
	* doc/cppopts.texi: Update.
testsuite:
	* gcc.dg/cpp/trad/Wunused.c, gcc.dg/cpp/trad/Wunused.h,
	gcc.dg/cpp/Wunused.c, gcc.dg/cpp/Wunused.h: New tests.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@55692 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 13 insertions, 7 deletions

diff --git a/gcc/cpplib.c b/gcc/cpplib.c
index c87572aba12..935a0e0b882 100644
--- a/gcc/cpplib.c
+++ b/gcc/cpplib.c
@@ -545,6 +545,9 @@ do_undef (pfile)
       if (node->flags & NODE_WARN)
 	cpp_error (pfile, DL_WARNING, "undefining \"%s\"", NODE_NAME (node));
 
+      if (CPP_OPTION (pfile, warn_unused_macros))
+	_cpp_warn_if_unused_macro (pfile, node, NULL);
+
       _cpp_free_definition (node);
     }
   check_eol (pfile);
@@ -1331,10 +1334,11 @@ do_ifdef (pfile)
       const cpp_hashnode *node = lex_macro_node (pfile);
 
       if (node)
-	skip = node->type != NT_MACRO;
-
-      if (node)
-	check_eol (pfile);
+	{
+	  skip = node->type != NT_MACRO;
+	  _cpp_mark_macro_used (node);
+	  check_eol (pfile);
+	}
     }
 
   push_conditional (pfile, skip, T_IFDEF, 0);
@@ -1351,11 +1355,13 @@ do_ifndef (pfile)
   if (! pfile->state.skipping)
     {
       node = lex_macro_node (pfile);
-      if (node)
-	skip = node->type == NT_MACRO;
 
       if (node)
-	check_eol (pfile);
+	{
+	  skip = node->type == NT_MACRO;
+	  _cpp_mark_macro_used (node);
+	  check_eol (pfile);
+	}
     }
 
   push_conditional (pfile, skip, T_IFNDEF, node);