[RFA:] cpplib, c-opts: Don't warn on dollars in builtin macro definitions.

[Hans-Peter Nilsson <hans-peter dot nilsson at axis dot com>]

Refer to the thread at
<URL:http://gcc.gnu.org/ml/gcc-bugs/2003-06/msg01231.html>.  Patch
as outlined in that discussion with Neil.  (There was pre-approval,
but for a different change with some misunderstanding involved,
so...)

Bootstrapped and tested (no Ada or treelang) on i686-pc-linux-gnu.
Built and tested on cris-axis-elf and cris-axis-linux-gnu, where it
fixes 6852 and 5746 regressions respectively.  Built and tested on
cross to mmix-knuth-mmixware and m32r-unknown-elf, no regressions.

Ok to commit?

	Don't warn on dollars in builtin macro definitions,
	e.g. __REGISTER_PREFIX__.
	* cpphash.h (struct cpp_reader): Move member warn_dollars...
	* cpplib.h (struct cpp_options): ...to here.  Change type to
	unsigned char.
	* cppinit.c (cpp_create_reader): Set it to 1 here.
	(post_options): Don't set it here.
	* c-opts.c (c_common_init_options): Reset it to 0 here.
	(finish_options): Set it here.
	* cpplex.c (forms_identifier_p): Tweak for new location of
	warn_dollars.

Index: cpphash.h
===================================================================
RCS file: /cvs/gcc/gcc/gcc/cpphash.h,v
retrieving revision 1.187
diff -p -c -r1.187 cpphash.h
*** cpphash.h	17 May 2003 20:29:29 -0000	1.187
--- cpphash.h	11 Jun 2003 13:35:50 -0000
*************** struct cpp_reader
*** 378,387 ****
    cpp_token avoid_paste;
    cpp_token eof;
  
-   /* True if we should warn about dollars in identifiers or numbers
-      for this translation unit.  */
-   bool warn_dollars;
- 
    /* Opaque handle to the dependencies of mkdeps.c.  */
    struct deps *deps;
  
--- 378,383 ----
Index: cpplib.h
===================================================================
RCS file: /cvs/gcc/gcc/gcc/cpplib.h,v
retrieving revision 1.254
diff -p -c -r1.254 cpplib.h
*** cpplib.h	11 May 2003 13:43:35 -0000	1.254
--- cpplib.h	11 Jun 2003 13:35:51 -0000
*************** struct cpp_options
*** 300,305 ****
--- 300,309 ----
    /* Zero means dollar signs are punctuation.  */
    unsigned char dollars_in_ident;
  
+   /* True if we should warn about dollars in identifiers or numbers
+      for this translation unit.  */
+   unsigned char warn_dollars;
+ 
    /* Nonzero means warn if undefined identifiers are evaluated in an #if.  */
    unsigned char warn_undef;
  
Index: cppinit.c
===================================================================
RCS file: /cvs/gcc/gcc/gcc/cppinit.c,v
retrieving revision 1.281
diff -p -c -r1.281 cppinit.c
*** cppinit.c	17 May 2003 20:29:30 -0000	1.281
--- cppinit.c	11 Jun 2003 13:35:51 -0000
*************** cpp_create_reader (lang, table)
*** 151,156 ****
--- 151,157 ----
    CPP_OPTION (pfile, warn_deprecated) = 1;
    CPP_OPTION (pfile, warn_long_long) = !CPP_OPTION (pfile, c99);
    CPP_OPTION (pfile, dollars_in_ident) = 1;
+   CPP_OPTION (pfile, warn_dollars) = 1;
  
    /* Default CPP arithmetic to something sensible for the host for the
       benefit of dumb users like fix-header.  */
*************** post_options (pfile)
*** 570,580 ****
        CPP_OPTION (pfile, trigraphs) = 0;
        CPP_OPTION (pfile, warn_trigraphs) = 0;
      }
- 
-   /* C99 permits implementation-defined characters in identifiers.
-      The documented meaning of -std= is to turn off extensions that
-      conflict with the specified standard, and since a strictly
-      conforming program cannot contain a '$', we do not condition
-      their acceptance on the -std= setting.  */
-   pfile->warn_dollars = CPP_PEDANTIC (pfile) && !CPP_OPTION (pfile, c99);
  }
--- 571,574 ----
Index: c-opts.c
===================================================================
RCS file: /cvs/gcc/gcc/gcc/c-opts.c,v
retrieving revision 1.54
diff -p -c -r1.54 c-opts.c
*** c-opts.c	8 Jun 2003 07:54:10 -0000	1.54
--- c-opts.c	11 Jun 2003 13:35:52 -0000
*************** c_common_init_options (lang)
*** 225,230 ****
--- 225,235 ----
  				ident_hash);
    cpp_opts = cpp_get_options (parse_in);
    cpp_opts->dollars_in_ident = DOLLARS_IN_IDENTIFIERS;
+ 
+   /* Reset to avoid warnings on internal definitions.  We set it just
+      before passing on command-line options to cpplib.  */
+   cpp_opts->warn_dollars = 0;
+ 
    if (flag_objc)
      cpp_opts->objc = 1;
  
*************** finish_options ()
*** 1356,1361 ****
--- 1361,1378 ----
        cpp_change_file (parse_in, LC_RENAME, _("<built-in>"));
        cpp_init_builtins (parse_in, flag_hosted);
        c_cpp_builtins (parse_in);
+ 
+       /* We're about to send user input to cpplib, so make it warn for
+ 	 things that we previously (when we sent it internal definitions)
+ 	 told it to not warn.
+ 
+ 	 C99 permits implementation-defined characters in identifiers.
+ 	 The documented meaning of -std= is to turn off extensions that
+ 	 conflict with the specified standard, and since a strictly
+ 	 conforming program cannot contain a '$', we do not condition
+ 	 their acceptance on the -std= setting.  */
+       cpp_opts->warn_dollars = (cpp_opts->pedantic && !cpp_opts->c99);
+ 
        cpp_change_file (parse_in, LC_RENAME, _("<command line>"));
        for (i = 0; i < deferred_count; i++)
  	{
Index: cpplex.c
===================================================================
RCS file: /cvs/gcc/gcc/gcc/cpplex.c,v
retrieving revision 1.235
diff -p -c -r1.235 cpplex.c
*** cpplex.c	17 May 2003 20:29:31 -0000	1.235
--- cpplex.c	11 Jun 2003 13:35:53 -0000
***************
*** 1,5 ****
  /* CPP Library - lexical analysis.
!    Copyright (C) 2000, 2001, 2002 Free Software Foundation, Inc.
     Contributed by Per Bothner, 1994-95.
     Based on CCCP program by Paul Rubin, June 1986
     Adapted to ANSI C, Richard Stallman, Jan 1987
--- 1,5 ----
  /* CPP Library - lexical analysis.
!    Copyright (C) 2000, 2001, 2002, 2003 Free Software Foundation, Inc.
     Contributed by Per Bothner, 1994-95.
     Based on CCCP program by Paul Rubin, June 1986
     Adapted to ANSI C, Richard Stallman, Jan 1987
*************** forms_identifier_p (pfile, first)
*** 402,410 ****
  	return false;
  
        buffer->cur++;
!       if (pfile->warn_dollars && !pfile->state.skipping)
  	{
! 	  pfile->warn_dollars = false;
  	  cpp_error (pfile, DL_PEDWARN, "'$' in identifier or number");
  	}
  
--- 402,410 ----
  	return false;
  
        buffer->cur++;
!       if (CPP_OPTION (pfile, warn_dollars) && !pfile->state.skipping)
  	{
! 	  CPP_OPTION (pfile, warn_dollars) = 0;
  	  cpp_error (pfile, DL_PEDWARN, "'$' in identifier or number");
  	}
  
brgds, H-P