cpplib: Update docs, make __STDC_HOSTED__ a Standard Macro

[Neil Booth <neil at daikokuya dot co dot uk>]

Andreas noticed the docs for -undef weren't clear.  In clarifying
them, I noticed we were treating __STDC_HOSTED__ incorrectly.

Neil.

	* c-cppbuiltin.c (c_cpp_builtins): Move __STDC_HOSTED__ into
	cpplib as it's a Standard Predefined Macro.
	* c-opts.c (finish_options): Pass flag_hosted to cpp_init_builtins.
	* cppinit.c (_cpp_init_builtins): Take HOSTED.  Define
	__STDC_HOSTED__ appropriately.
	* cpplib.h (_cpp_init_builtins): Update.
	* fix-header.c (read_scan_file): Update.
	* doc/cpp.texi, doc/cppopts.texi: Update documentation.

Index: c-cppbuiltin.c
===================================================================
RCS file: /cvs/gcc/gcc/gcc/c-cppbuiltin.c,v
retrieving revision 1.7
diff -u -p -r1.7 c-cppbuiltin.c
--- c-cppbuiltin.c	15 Mar 2003 13:43:24 -0000	1.7
+++ c-cppbuiltin.c	10 May 2003 15:00:22 -0000
@@ -355,11 +355,6 @@ c_cpp_builtins (pfile)
   if (optimize)
     cpp_define (pfile, "__OPTIMIZE__");
 
-  if (flag_hosted)
-    cpp_define (pfile, "__STDC_HOSTED__=1");
-  else
-    cpp_define (pfile, "__STDC_HOSTED__=0");
-
   if (fast_math_flags_set_p ())
     cpp_define (pfile, "__FAST_MATH__");
   if (flag_really_no_inline)
Index: c-opts.c
===================================================================
RCS file: /cvs/gcc/gcc/gcc/c-opts.c,v
retrieving revision 1.43
diff -u -p -r1.43 c-opts.c
--- c-opts.c	6 May 2003 20:42:32 -0000	1.43
+++ c-opts.c	10 May 2003 15:00:23 -0000
@@ -1790,7 +1790,7 @@ finish_options ()
       size_t i;
 
       cpp_change_file (parse_in, LC_RENAME, _("<built-in>"));
-      cpp_init_builtins (parse_in);
+      cpp_init_builtins (parse_in, flag_hosted);
       c_cpp_builtins (parse_in);
       cpp_change_file (parse_in, LC_RENAME, _("<command line>"));
       for (i = 0; i < deferred_count; i++)
Index: cppinit.c
===================================================================
RCS file: /cvs/gcc/gcc/gcc/cppinit.c,v
retrieving revision 1.277
diff -u -p -r1.277 cppinit.c
--- cppinit.c	4 May 2003 20:03:54 -0000	1.277
+++ cppinit.c	10 May 2003 15:00:23 -0000
@@ -327,10 +327,12 @@ mark_named_operators (pfile)
 }
 
 /* Read the builtins table above and enter them, and language-specific
-   macros, into the hash table.  */
+   macros, into the hash table.  HOSTED is true if this is a hosted
+   environment.  */
 void
-cpp_init_builtins (pfile)
+cpp_init_builtins (pfile, hosted)
      cpp_reader *pfile;
+     int hosted;
 {
   const struct builtin *b;
   size_t n = ARRAY_SIZE (builtin_array);
@@ -354,6 +356,11 @@ cpp_init_builtins (pfile)
     _cpp_define_builtin (pfile, "__STDC_VERSION__ 199409L");
   else if (CPP_OPTION (pfile, c99))
     _cpp_define_builtin (pfile, "__STDC_VERSION__ 199901L");
+
+  if (hosted)
+    cpp_define (pfile, "__STDC_HOSTED__=1");
+  else
+    cpp_define (pfile, "__STDC_HOSTED__=0");
 
   if (CPP_OPTION (pfile, objc))
     _cpp_define_builtin (pfile, "__OBJC__ 1");
Index: cpplib.h
===================================================================
RCS file: /cvs/gcc/gcc/gcc/cpplib.h,v
retrieving revision 1.253
diff -u -p -r1.253 cpplib.h
--- cpplib.h	23 Apr 2003 22:43:58 -0000	1.253
+++ cpplib.h	10 May 2003 15:00:23 -0000
@@ -526,7 +526,7 @@ extern void cpp_set_callbacks PARAMS ((c
 extern const char *cpp_read_main_file PARAMS ((cpp_reader *, const char *));
 
 /* Set up built-ins like __FILE__.  */
-extern void cpp_init_builtins PARAMS ((cpp_reader *));
+extern void cpp_init_builtins PARAMS ((cpp_reader *, int));
 
 /* Call this to finish preprocessing.  If you requested dependency
    generation, pass an open stream to write the information to,
Index: fix-header.c
===================================================================
RCS file: /cvs/gcc/gcc/gcc/fix-header.c,v
retrieving revision 1.94
diff -u -p -r1.94 fix-header.c
--- fix-header.c	19 Apr 2003 00:22:49 -0000	1.94
+++ fix-header.c	10 May 2003 15:00:24 -0000
@@ -636,7 +636,7 @@ read_scan_file (in_fname, argc, argv)
     exit (FATAL_EXIT_CODE);
 
   cpp_change_file (scan_in, LC_RENAME, "<built-in>");
-  cpp_init_builtins (scan_in);
+  cpp_init_builtins (scan_in, true);
   cpp_change_file (scan_in, LC_RENAME, in_fname);
 
   /* Process switches after builtins so -D can override them.  */
Index: doc/cpp.texi
===================================================================
RCS file: /cvs/gcc/gcc/gcc/doc/cpp.texi,v
retrieving revision 1.55
diff -u -p -r1.55 cpp.texi
--- doc/cpp.texi	4 May 2003 20:03:54 -0000	1.55
+++ doc/cpp.texi	10 May 2003 15:00:26 -0000
@@ -264,15 +264,14 @@ complete support for international chara
 
 Different systems use different conventions to indicate the end of a
 line.  GCC accepts the ASCII control sequences @kbd{LF}, @kbd{@w{CR
-LF}}, @kbd{CR}, and @kbd{@w{LF CR}} as end-of-line markers.  The first
-three are the canonical sequences used by Unix, DOS and VMS, and the
+LF}}, @kbd{CR} as end-of-line markers.  These
+are the canonical sequences used by Unix, DOS and VMS, and the
 classic Mac OS (before OSX) respectively.  You may therefore safely copy
 source code written on any of those systems to a different one and use
 it without conversion.  (GCC may lose track of the current line number
 if a file doesn't consistently use one convention, as sometimes happens
 when it is edited on computers with different conventions that share a
-network file system.)  @kbd{@w{LF CR}} is included because it has been
-reported as an end-of-line marker under exotic conditions.
+network file system.)
 
 If the last line of any input file lacks an end-of-line marker, the end
 of the file is considered to implicitly supply one.  The C standard says
@@ -1733,7 +1732,7 @@ predefined macros, but you cannot undefi
 @subsection Standard Predefined Macros
 @cindex standard predefined macros.
 
-The standard predefined macros are specified by the C and/or C++
+The standard predefined macros are specified by the relevant
 language standards, so they are available with all compilers that
 implement those standards.  Older compilers may not provide all of
 them.  Their names all start with double underscores.
@@ -1852,6 +1851,14 @@ of the 1998 C++ standard will define thi
 GNU C++ compiler is not yet fully conforming, so it uses @code{1}
 instead.  We hope to complete our implementation in the near future.
 
+@item __OBJC__
+This macro is defined, with value 1, when the Objective-C compiler is in
+use.  You can use @code{__OBJC__} to test whether a header is compiled
+by a C compiler or a Objective-C compiler.
+
+@item __ASSEMBLER__
+This macro is defined with value 1 when preprocessing assembler.
+
 @end table
 
 @node Common Predefined Macros
@@ -1912,11 +1919,6 @@ calculate a single number, then compare 
 
 @noindent
 Many people find this form easier to understand.
-
-@item __OBJC__
-This macro is defined, with value 1, when the Objective-C compiler is in
-use.  You can use @code{__OBJC__} to test whether a header is compiled
-by a C compiler or a Objective-C compiler.
 
 @item __GNUG__
 The GNU C++ compiler defines this.  Testing it is equivalent to
Index: doc/cppopts.texi
===================================================================
RCS file: /cvs/gcc/gcc/gcc/doc/cppopts.texi,v
retrieving revision 1.21
diff -u -p -r1.21 cppopts.texi
--- doc/cppopts.texi	4 May 2003 22:06:57 -0000	1.21
+++ doc/cppopts.texi	10 May 2003 15:00:26 -0000
@@ -40,8 +40,11 @@ provided with a @option{-D} option.
 
 @item -undef
 @opindex undef
-Do not predefine any system-specific macros.  The common predefined
-macros remain defined.
+Do not predefine any system-specific or GCC-specific macros.  The
+standard predefined macros remain defined.
+@ifset cppmanual
+@xref{Standard Predefined Macros}
+@end ifset
 
 @item -I @var{dir}
 @opindex I