* cppexp.c (parse_defined): Always record the macro name.

	(lex): Don't worry about identifiers, or special-case
	CPP_NOT here.
	(_cpp_parse_expr): Figure out at the end of the routine
	whether we saw a valid !defined() expression.
	* cppfiles.c (stack_include_file): Update for mi_valid.
	(_cpp_pop_file_buffer): Similarly.
	* cpplex.c (_cpp_lex_token): Similarly.
	* cpphash.h (enum mi_state, enum mi_ind, mi_state,
	mi_if_not_defined, mi_lexed): Remove.
	(mi_valid): New.
	* cpplib.c (do_if): Simplify.
	(do_endif, push_conditional, _cpp_handle_directive): Update
	for renaming of mi_state to mi_valid.

	* cpp.texi: Add index entries for digraphs, and add comment
	that C++ refers to them as alternative tokens.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@44459 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 13 insertions, 17 deletions

diff --git a/gcc/cpplib.c b/gcc/cpplib.c
index c196c1f9c96..8f9f54c8be6 100644
--- a/gcc/cpplib.c
+++ b/gcc/cpplib.c
@@ -358,7 +358,7 @@ _cpp_handle_directive (pfile, indented)
 	      /* If we have a directive that is not an opening
 		 conditional, invalidate any control macro.  */
 	      if (! (dir->flags & IF_COND))
-		pfile->mi_state = MI_FAILED;
+		pfile->mi_valid = false;
 
 	      (*dir->handler) (pfile);
 	    }
@@ -1278,27 +1278,22 @@ do_ifndef (pfile)
   push_conditional (pfile, skip, T_IFNDEF, node);
 }
 
-/* #if cooperates with parse_defined to handle multiple-include
-   optimisations.  If macro expansions or identifiers appear in the
-   expression, we cannot treat it as a controlling conditional, since
-   their values could change in the future.  */
+/* _cpp_parse_expr puts a macro in a "#if !defined ()" expression in
+   pfile->mi_ind_cmacro so we can handle multiple-include
+   optimisations.  If macro expansion occurs in the expression, we
+   cannot treat it as a controlling conditional, since the expansion
+   could change in the future.  That is handled by cpp_get_token.  */
 
 static void
 do_if (pfile)
      cpp_reader *pfile;
 {
   int skip = 1;
-  const cpp_hashnode *cmacro = 0;
 
   if (! pfile->state.skipping)
-    {
-      /* Controlling macro of #if ! defined ()  */
-      pfile->mi_ind_cmacro = 0;
-      skip = _cpp_parse_expr (pfile) == 0;
-      cmacro = pfile->mi_ind_cmacro;
-    }
+    skip = _cpp_parse_expr (pfile) == 0;
 
-  push_conditional (pfile, skip, T_IF, cmacro);
+  push_conditional (pfile, skip, T_IF, pfile->mi_ind_cmacro);
 }
 
 /* Flip skipping state if appropriate and continue without changing
@@ -1395,7 +1390,7 @@ do_endif (pfile)
       /* If potential control macro, we go back outside again.  */
       if (ifs->next == 0 && ifs->mi_cmacro)
 	{
-	  pfile->mi_state = MI_OUTSIDE;
+	  pfile->mi_valid = true;
 	  pfile->mi_cmacro = ifs->mi_cmacro;
 	}
 
@@ -1406,8 +1401,8 @@ do_endif (pfile)
 }
 
 /* Push an if_stack entry and set pfile->state.skipping accordingly.
-   If this is a #ifndef starting at the beginning of a file,
-   CMACRO is the macro name tested by the #ifndef.  */
+   If this is a #if or #ifndef, CMACRO is a potentially controlling
+   macro - we need to check here that we are at the top of the file.  */
 
 static void
 push_conditional (pfile, skip, type, cmacro)
@@ -1425,7 +1420,8 @@ push_conditional (pfile, skip, type, cmacro)
   ifs->skip_elses = pfile->state.skipping || !skip;
   ifs->was_skipping = pfile->state.skipping;
   ifs->type = type;
-  if (pfile->mi_state == MI_OUTSIDE && pfile->mi_cmacro == 0)
+  /* This condition is effectively a test for top-of-file.  */
+  if (pfile->mi_valid && pfile->mi_cmacro == 0)
     ifs->mi_cmacro = cmacro;
   else
     ifs->mi_cmacro = 0;