* Makefile.in (cppexp.o): Depend on cpphash.h.

	* cppexp.c (cpp_lex): Handle `defined (xxx)' for poisoned xxx.
	Include cpphash.h.
	* cpphash.c (special_symbol): Handle plain `xxx' for poisoned xxx.
	* cpplib.c (do_define): Generalise to handle poisoned definitions,
	redefining poisoned identifiers, etc.
	(do_undef): Don't allow poisoned identifiers to be undefined.
	(do_pragma): Add #pragma poison.
	(do_xifdef): Handle `#ifdef xxx' for poisoned xxx.

	* cccp.c: Add T_POISON node type.
	(special_symbol): Handle `defined(xxx)' and plain `xxx' for
	poisoned xxx.
	(do_define): Generalise to handle poisoned definitions,
	redefining poisoned identifiers, etc.
	(do_undef): Don't allow poisoned identifiers to be undefined.
	(do_pragma): Add #pragma poison.
	(do_xifdef): Handle `#ifdef xxx' for poisoned xxx.

	* c-pragma.c (handle_pragma_token): Ignore #pragma poison.
	* c-pragma.h: Add ps_poison state.  We now always have generic
	pragmas.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@29224 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 10 insertions, 3 deletions

diff --git a/gcc/cppexp.c b/gcc/cppexp.c
index 330236ebeb7..f037924d927 100644
--- a/gcc/cppexp.c
+++ b/gcc/cppexp.c
@@ -27,6 +27,7 @@ Written by Per Bothner 1994.  */
 #include "config.h"
 #include "system.h"
 #include "cpplib.h"
+#include "cpphash.h"
 
 #ifdef MULTIBYTE_CHARS
 #include <locale.h>
@@ -445,6 +446,7 @@ cpp_lex (pfile, skip_evaluation)
 	  int paren = 0, len;
 	  cpp_buffer *ip = CPP_BUFFER (pfile);
 	  U_CHAR *tok;
+	  HASHNODE *hp;
 
 	  cpp_skip_hspace (pfile);
 	  if (*ip->cur == '(')
@@ -469,9 +471,14 @@ cpp_lex (pfile, skip_evaluation)
 		goto oops;
 	      ++ip->cur;
 	    }
-	  if (cpp_lookup (pfile, tok, len, -1))
-	    op.value = 1;
-
+	  hp = cpp_lookup (pfile, tok, len, -1);
+	  if (hp != NULL)
+	    {
+	      if (hp->type == T_POISON)
+		cpp_error (pfile, "attempt to use poisoned `%s'", hp->name);
+	      else
+		op.value = 1;
+	    }
 	}
       return op;