Add ability to force lexed tokens' source_locations.

Use it to force BUILTINS_LOCATION when declaring builtins instead of creating a <built-in> entry in the line_table which is wrong.

	* c-opts.c (c_finish_options): Force BUILTINS_LOCATION for tokens
	defined in cpp_init_builtins and c_cpp_builtins.

	gcc/fortran/ChangeLog
	* cpp.c (gfc_cpp_init): Force BUILTINS_LOCATION for tokens
	defined in cpp_define_builtins.

	libcpp/ChangeLog
	* init.c (cpp_create_reader): Inititalize forced_token_location_p.
	* internal.h (struct cpp_reader): Add field forced_token_location_p.
	* lex.c (_cpp_lex_direct): Use forced_token_location_p.
	(cpp_force_token_locations): New.
	(cpp_stop_forcing_token_locations): New.

From-SVN: r177973

5 files changed, 42 insertions, 2 deletions

diff --git a/libcpp/ChangeLog b/libcpp/ChangeLog
index 81b3a94bb50..8a5e89921a0 100644
--- a/libcpp/ChangeLog
+++ b/libcpp/ChangeLog
@@ -1,3 +1,11 @@
+2011-08-22  Gabriel Charette  <gchare@google.com>
+
+	* init.c (cpp_create_reader): Inititalize forced_token_location_p.
+	* internal.h (struct cpp_reader): Add field forced_token_location_p.
+	* lex.c (_cpp_lex_direct): Use forced_token_location_p.
+	(cpp_force_token_locations): New.
+	(cpp_stop_forcing_token_locations): New.
+
 2011-08-18  Rainer Orth  <ro@CeBiTec.Uni-Bielefeld.DE>
 
 	PR libstdc++/1773
diff --git a/libcpp/include/cpplib.h b/libcpp/include/cpplib.h
index 4d68fa76b09..0e90821072f 100644
--- a/libcpp/include/cpplib.h
+++ b/libcpp/include/cpplib.h
@@ -989,4 +989,8 @@ extern void cpp_prepare_state (cpp_reader *, struct save_macro_data **);
 extern int cpp_read_state (cpp_reader *, const char *, FILE *,
 			   struct save_macro_data *);
 
+/* In lex.c */
+extern void cpp_force_token_locations (cpp_reader *, source_location *);
+extern void cpp_stop_forcing_token_locations (cpp_reader *);
+
 #endif /* ! LIBCPP_CPPLIB_H */
diff --git a/libcpp/init.c b/libcpp/init.c
index 93f12d0d71f..c5c53256d35 100644
--- a/libcpp/init.c
+++ b/libcpp/init.c
@@ -223,6 +223,9 @@ cpp_create_reader (enum c_lang lang, hash_table *table,
   /* Initialize table for push_macro/pop_macro.  */
   pfile->pushed_macros = 0;
 
+  /* Do not force token locations by default.  */
+  pfile->forced_token_location_p = NULL;
+
   /* The expression parser stack.  */
   _cpp_expand_op_stack (pfile);
 
diff --git a/libcpp/internal.h b/libcpp/internal.h
index d2872c4a11f..6c423f056bc 100644
--- a/libcpp/internal.h
+++ b/libcpp/internal.h
@@ -499,6 +499,10 @@ struct cpp_reader
 
   /* List of saved macros by push_macro.  */
   struct def_pragma_macro *pushed_macros;
+
+  /* If non-null, the lexer will use this location for the next token
+     instead of getting a location from the linemap.  */
+  source_location *forced_token_location_p;
 };
 
 /* Character classes.  Based on the more primitive macros in safe-ctype.h.
diff --git a/libcpp/lex.c b/libcpp/lex.c
index 463b5c80eee..75b2b1dc7ff 100644
--- a/libcpp/lex.c
+++ b/libcpp/lex.c
@@ -1975,8 +1975,11 @@ _cpp_lex_direct (cpp_reader *pfile)
     }
   c = *buffer->cur++;
 
-  result->src_loc = linemap_position_for_column (pfile->line_table,
-			                                    CPP_BUF_COLUMN (buffer, buffer->cur));
+  if (pfile->forced_token_location_p)
+    result->src_loc = *pfile->forced_token_location_p;
+  else
+    result->src_loc = linemap_position_for_column (pfile->line_table,
+					  CPP_BUF_COLUMN (buffer, buffer->cur));
 
   switch (c)
     {
@@ -2839,3 +2842,21 @@ cpp_token_val_index (cpp_token *tok)
       return CPP_TOKEN_FLD_NONE;
     }
 }
+
+/* All tokens lexed in R after calling this function will be forced to have
+   their source_location the same as the location referenced by P, until
+   cpp_stop_forcing_token_locations is called for R.  */
+
+void
+cpp_force_token_locations (cpp_reader *r, source_location *p)
+{
+  r->forced_token_location_p = p;
+}
+
+/* Go back to assigning locations naturally for lexed tokens.  */
+
+void
+cpp_stop_forcing_token_locations (cpp_reader *r)
+{
+  r->forced_token_location_p = NULL;
+}