directives-only.c: New file.

	libcpp/
	* directives-only.c: New file.
	* internal.h (struct _cpp_dir_only_callbacks): New.
	(_cpp_preprocess_dir_only): New function.
	* directives.c (_cpp_handle_directive): Check directives_only before
	disabling execution of indented directives.
	* files.c (_cpp_stack_file): Add directives_only check.
	* include/cpplib.h (struct cpp_options): Add directives_only.
	(cpp_init_special_builtins): New function.
	* init.c (cpp_init_special_builtins): New function.
	(cpp_init_builtins): Move builtin_array initialization to
	cpp_init_special_builtins.
	(post_options): Check directives_only before setting
	pfile->state.prevent_expansion = 1.
	* macro.c (_cpp_builtin_macro_text): Print an error if __COUNTER__
	is expanded inside a directive while -fdirectives-only is enabled.
	* Makefile.in (libcpp_a_OBJS): Add directives-only.o.
	(libcpp_a_SOURCES): Add directives-only.c.

	gcc/
	* c-ppoutput.c (print_lines_directives_only): New function.
	(scan_translation_unit_directives_only): New function.
	(preprocess_file): Add call to scan_translation_unit_directives_only.
	* c-opts.c (c_common_handle_option): Add OPT_fdirectives_only.
	(sanitize_cpp_opts): Add default flag_dump_macros setting for
	-fdirectives-only.  Add errors for -fdirectives-only conflict with
	-Wunused-macros and -traditional.
	(finish_options): Add builtin macro initialization for
	-fdirectives-only + -fpreprocessed.
	* c.opt (fdirectives-only): New.
	* doc/cppopts.texi (fdirectives-only): New.

	gcc/testsuite/
	* gcc.dg/cpp/counter-2.c: New test.
	* gcc.dg/cpp/counter-3.c: New test.
	* gcc.dg/cpp/dir-only-1.c: New test.
	* gcc.dg/cpp/dir-only-1.h: New file.
	* gcc.dg/cpp/dir-only-2.c: New test.
	* gcc.dg/cpp/dir-only-3.c: New test.
	* gcc.dg/cpp/dir-only-3a.h: New file.
	* gcc.dg/cpp/dir-only-3b.h: New file.
	* gcc.dg/cpp/dir-only-4.c: New test.
	* gcc.dg/cpp/dir-only-5.c: New test.
	* gcc.dg/cpp/dir-only-6.c: New test.

From-SVN: r127066

17 files changed, 259 insertions, 0 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 3e62b14..a2371b0 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,17 @@
+2007-07-30  Ollie Wild  <aaw@google.com>
+
+	* c-ppoutput.c (print_lines_directives_only): New function.
+	(scan_translation_unit_directives_only): New function.
+	(preprocess_file): Add call to scan_translation_unit_directives_only.
+	* c-opts.c (c_common_handle_option): Add OPT_fdirectives_only.
+	(sanitize_cpp_opts): Add default flag_dump_macros setting for
+	-fdirectives-only.  Add errors for -fdirectives-only conflict with
+	-Wunused-macros and -traditional.
+	(finish_options): Add builtin macro initialization for
+	-fdirectives-only + -fpreprocessed.
+	* c.opt (fdirectives-only): New.
+	* doc/cppopts.texi (fdirectives-only): New.
+
 2007-07-30  Kaveh R. Ghazi  <ghazi@caip.rutgers.edu>
 
 	* alias.c (record_set, memory_modified_1): Constify.
diff --git a/gcc/c-opts.c b/gcc/c-opts.c
index a78c692..a637ffc 100644
--- a/gcc/c-opts.c
+++ b/gcc/c-opts.c
@@ -618,6 +618,10 @@ c_common_handle_option (size_t scode, const char *arg, int value)
 	disable_builtin_function (arg);
       break;
 
+    case OPT_fdirectives_only:
+      cpp_opts->directives_only = 1;
+      break;
+
     case OPT_fdollars_in_identifiers:
       cpp_opts->dollars_in_ident = value;
       break;
@@ -1406,6 +1410,11 @@ sanitize_cpp_opts (void)
   if (flag_dump_macros == 'M')
     flag_no_output = 1;
 
+  /* By default, -fdirectives-only implies -dD.  This allows subsequent phases
+     to perform proper macro expansion.  */
+  if (cpp_opts->directives_only && !cpp_opts->preprocessed && !flag_dump_macros)
+    flag_dump_macros = 'D';
+
   /* Disable -dD, -dN and -dI if normal output is suppressed.  Allow
      -dM since at least glibc relies on -M -dM to work.  */
   /* Also, flag_no_output implies flag_no_line_commands, always.  */
@@ -1436,6 +1445,14 @@ sanitize_cpp_opts (void)
      actually output the current directory?  */
   if (flag_working_directory == -1)
     flag_working_directory = (debug_info_level != DINFO_LEVEL_NONE);
+
+  if (cpp_opts->directives_only)
+    {
+      if (warn_unused_macros)
+	error ("-fdirectives-only is incompatible with -Wunused_macros");
+      if (cpp_opts->traditional)
+	error ("-fdirectives-only is incompatible with -traditional");
+    }
 }
 
 /* Add include path with a prefix at the front of its name.  */
@@ -1519,6 +1536,8 @@ finish_options (void)
 	    }
 	}
     }
+  else if (cpp_opts->directives_only)
+    cpp_init_special_builtins (parse_in);
 
   include_cursor = 0;
   push_command_line_include ();
diff --git a/gcc/c-ppoutput.c b/gcc/c-ppoutput.c
index 6c44095..22ee0f6 100644
--- a/gcc/c-ppoutput.c
+++ b/gcc/c-ppoutput.c
@@ -41,6 +41,8 @@ static struct
 
 /* General output routines.  */
 static void scan_translation_unit (cpp_reader *);
+static void print_lines_directives_only (int, const void *, size_t);
+static void scan_translation_unit_directives_only (cpp_reader *);
 static void scan_translation_unit_trad (cpp_reader *);
 static void account_for_newlines (const unsigned char *, size_t);
 static int dump_macro (cpp_reader *, cpp_hashnode *, void *);
@@ -75,6 +77,9 @@ preprocess_file (cpp_reader *pfile)
     }
   else if (cpp_get_options (pfile)->traditional)
     scan_translation_unit_trad (pfile);
+  else if (cpp_get_options (pfile)->directives_only
+	   && !cpp_get_options (pfile)->preprocessed)
+    scan_translation_unit_directives_only (pfile);
   else
     scan_translation_unit (pfile);
 
@@ -179,6 +184,26 @@ scan_translation_unit (cpp_reader *pfile)
     }
 }
 
+static void
+print_lines_directives_only (int lines, const void *buf, size_t size)
+{
+  print.src_line += lines;
+  fwrite (buf, 1, size, print.outf);
+}
+
+/* Writes out the preprocessed file, handling spacing and paste
+   avoidance issues.  */
+static void
+scan_translation_unit_directives_only (cpp_reader *pfile)
+{
+  struct _cpp_dir_only_callbacks cb;
+
+  cb.print_lines = print_lines_directives_only;
+  cb.maybe_print_line = maybe_print_line;
+
+  _cpp_preprocess_dir_only (pfile, &cb);
+}
+
 /* Adjust print.src_line for newlines embedded in output.  */
 static void
 account_for_newlines (const unsigned char *str, size_t len)
diff --git a/gcc/c.opt b/gcc/c.opt
index 6534569..37c55be 100644
--- a/gcc/c.opt
+++ b/gcc/c.opt
@@ -523,6 +523,10 @@ fdefault-inline
 C++ ObjC++
 Inline member functions by default
 
+fdirectives-only
+C ObjC C++ ObjC++
+Preprocess directives only.
+
 fdollars-in-identifiers
 C ObjC C++ ObjC++
 Permit '$' as an identifier character
diff --git a/gcc/doc/cppopts.texi b/gcc/doc/cppopts.texi
index 73db832..dbc8f0e 100644
--- a/gcc/doc/cppopts.texi
+++ b/gcc/doc/cppopts.texi
@@ -518,6 +518,28 @@ Search @var{dir} only for header files requested with
 If @var{dir} begins with @code{=}, then the @code{=} will be replaced
 by the sysroot prefix; see @option{--sysroot} and @option{-isysroot}.
 
+@item -fdirectives-only
+@opindex fdirectives-only
+When preprocessing, handle directives, but do not expand macros.
+
+The option's behavior depends on the @option{-E} and @option{-fpreprocessed}
+options.
+
+With @option{-E}, preprocessing is limited to the handling of directives
+such as @code{#define}, @code{#ifdef}, and @code{#error}.  Other
+preprocessor operations, such as macro expansion and trigraph
+conversion are not performed.  In addition, the @option{-dD} option is
+implicitly enabled.
+
+With @option{-fpreprocessed}, predefinition of command line and most
+builtin macros is disabled.  Macros such as @code{__LINE__}, which are
+contextually dependent, are handled normally.  This enables compilation of
+files previously preprocessed with @code{-E -fdirectives-only}.
+
+With both @option{-E} and @option{-fpreprocessed}, the rules for
+@option{-fpreprocessed} take precedence.  This enables full preprocessing of
+files previously preprocessed with @code{-E -fdirectives-only}.
+
 @item -fdollars-in-identifiers
 @opindex fdollars-in-identifiers
 @anchor{fdollars-in-identifiers}
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index b7681c3..7d6cd5e 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,17 @@
+2007-07-30  Ollie Wild  <aaw@google.com>
+
+	* gcc.dg/cpp/counter-2.c: New test.
+	* gcc.dg/cpp/counter-3.c: New test.
+	* gcc.dg/cpp/dir-only-1.c: New test.
+	* gcc.dg/cpp/dir-only-1.h: New file.
+	* gcc.dg/cpp/dir-only-2.c: New test.
+	* gcc.dg/cpp/dir-only-3.c: New test.
+	* gcc.dg/cpp/dir-only-3a.h: New file.
+	* gcc.dg/cpp/dir-only-3b.h: New file.
+	* gcc.dg/cpp/dir-only-4.c: New test.
+	* gcc.dg/cpp/dir-only-5.c: New test.
+	* gcc.dg/cpp/dir-only-6.c: New test.
+
 2007-07-30  Julian Brown  <julian@codesourcery.com>
 
 	* gcc.target/arm/neon/v*.c: Regenerate.
diff --git a/gcc/testsuite/gcc.dg/cpp/counter-2.c b/gcc/testsuite/gcc.dg/cpp/counter-2.c
new file mode 100644
index 0000000..7d6578d
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/cpp/counter-2.c
@@ -0,0 +1,14 @@
+/* Copyright 2007 Free Software Foundation, Inc.
+   Contributed by Ollie Wild <aaw@google.com>.  */
+
+/* { dg-do preprocess } */
+/* { dg-options -fdirectives-only } */
+
+/* Tests __COUNTER__ macro expansion is disabled inside directives with
+   -fdirectives-only. */
+
+#ifdef __COUNTER__  /* Macro not expanded. */
+#endif
+
+#if __COUNTER__ == 0  /* { dg-error "__COUNTER__ expanded inside directive with -fdirectives-only" } */
+#endif
diff --git a/gcc/testsuite/gcc.dg/cpp/counter-3.c b/gcc/testsuite/gcc.dg/cpp/counter-3.c
new file mode 100644
index 0000000..3b1824f
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/cpp/counter-3.c
@@ -0,0 +1,10 @@
+/* Copyright 2007 Free Software Foundation, Inc.
+   Contributed by Ollie Wild <aaw@google.com>.  */
+
+/* { dg-do preprocess } */
+/* { dg-options "-fdirectives-only -fpreprocessed" } */
+
+/* Tests __COUNTER__ macro expansion is enabled outside directives with
+   -fdirectives-only. */
+
+int zero = __COUNTER__;
diff --git a/gcc/testsuite/gcc.dg/cpp/dir-only-1.c b/gcc/testsuite/gcc.dg/cpp/dir-only-1.c
new file mode 100644
index 0000000..3c22616
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/cpp/dir-only-1.c
@@ -0,0 +1,73 @@
+/* Copyright 2007 Free Software Foundation, Inc.
+   Contributed by Ollie Wild <aaw@google.com>.  */
+
+/* { dg-do preprocess } */
+/* { dg-options -fdirectives-only } */
+
+/* Tests scan_translation_unit_directives_only()'s handling of corner cases. */
+
+/* Ignore directives inside block comments...
+#error directive inside block comment
+*/
+
+// Escaped newline doesn't terminate line comment \
+#error directive inside line comment
+
+/* A comment canot start inside a string. */
+const char *c1 = "/*";
+#define NOT_IN_COMMENT
+const char *c2 = "*/";
+#ifndef NOT_IN_COMMENT
+#error Comment started inside a string literal
+#endif
+
+/* Escaped newline handling. */
+int i; \
+#error ignored escaped newline
+  \
+  \
+#define BOL
+#ifndef BOL
+#error escaped newline did not preserve beginning of line
+#endif
+
+/* Handles \\ properly at the end of a string. */
+"string ends in \\"/*
+#error Missed string terminator.
+*/
+
+/* Handles macro expansion in preprocessing directives. */
+#define HEADER "dir-only-1.h"
+#include HEADER
+#ifndef GOT_HEADER
+#error Failed to include header.
+#endif
+
+/\
+*
+#define IN_COMMENT
+*/
+#ifdef IN_COMMENT
+#error Escaped newline breaks block comment initiator.
+#endif
+
+/*
+*\
+/
+#define NOT_IN_COMMENT2
+/**/
+#ifndef NOT_IN_COMMENT2
+#error Escaped newline breaks block comment terminator.
+#endif
+
+/* Test escaped newline inside character escape sequence. */
+"\\
+\"/*
+#error Missed string terminator
+*/
+
+/* Block comments don't mask trailing preprocessing
+   directive. */ #define NOT_MASKED
+#ifndef NOT_MASKED
+#error Comment masks trailing directive.
+#endif
diff --git a/gcc/testsuite/gcc.dg/cpp/dir-only-1.h b/gcc/testsuite/gcc.dg/cpp/dir-only-1.h
new file mode 100644
index 0000000..96dbcc0
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/cpp/dir-only-1.h
@@ -0,0 +1,3 @@
+/* Copyright 2007 Free Software Foundation, Inc.
+   Contributed by Ollie Wild <aaw@google.com>.  */
+#define GOT_HEADER
diff --git a/gcc/testsuite/gcc.dg/cpp/dir-only-2.c b/gcc/testsuite/gcc.dg/cpp/dir-only-2.c
new file mode 100644
index 0000000..489b4d6
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/cpp/dir-only-2.c
@@ -0,0 +1,12 @@
+/* Copyright 2007 Free Software Foundation, Inc.
+   Contributed by Ollie Wild <aaw@google.com>.  */
+
+/* { dg-do preprocess } */
+/* { dg-options "-fpreprocessed -fdirectives-only -DNOT_SET" } */
+
+/* Tests -fdirectives-only + -fpreprocessed. */
+
+/* Check this is not defined. */
+#ifdef NOT_SET
+#error Command line macro not disabled.
+#endif
diff --git a/gcc/testsuite/gcc.dg/cpp/dir-only-3.c b/gcc/testsuite/gcc.dg/cpp/dir-only-3.c
new file mode 100644
index 0000000..e6eaa01
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/cpp/dir-only-3.c
@@ -0,0 +1,13 @@
+/* Copyright 2007 Free Software Foundation, Inc.
+   Contributed by Ollie Wild <aaw@google.com>.  */
+
+/* { dg-do preprocess } */
+/* { dg-options "-fdirectives-only -H" } */
+/* { dg-message "dir-only-3a\.h\n\[^\n\]*dir-only-3b\.h\n\[^\n\]*dir-only-3a\.h\n" "include guard check" { target *-*-* } 0 } */
+
+/* Tests include guards. */
+
+#include "dir-only-3a.h"
+#include "dir-only-3b.h"
+#include "dir-only-3b.h"
+#include "dir-only-3a.h"
diff --git a/gcc/testsuite/gcc.dg/cpp/dir-only-3a.h b/gcc/testsuite/gcc.dg/cpp/dir-only-3a.h
new file mode 100644
index 0000000..6644bbf
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/cpp/dir-only-3a.h
@@ -0,0 +1,8 @@
+/* Copyright 2007 Free Software Foundation, Inc.
+   Contributed by Ollie Wild <aaw@google.com>.  */
+
+extern int outside_guard
+
+#ifndef DIR_ONLY_3A_H
+#define DIR_ONLY_3A_H
+#endif
diff --git a/gcc/testsuite/gcc.dg/cpp/dir-only-3b.h b/gcc/testsuite/gcc.dg/cpp/dir-only-3b.h
new file mode 100644
index 0000000..4edaa7b
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/cpp/dir-only-3b.h
@@ -0,0 +1,9 @@
+/* Copyright 2007 Free Software Foundation, Inc.
+   Contributed by Ollie Wild <aaw@google.com>.  */
+
+#ifndef DIR_ONLY_3B_H
+#define DIR_ONLY_3B_H
+
+extern int inside guard;
+
+#endif
diff --git a/gcc/testsuite/gcc.dg/cpp/dir-only-4.c b/gcc/testsuite/gcc.dg/cpp/dir-only-4.c
new file mode 100644
index 0000000..a7b5f04
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/cpp/dir-only-4.c
@@ -0,0 +1,6 @@
+/* Copyright 2007 Free Software Foundation, Inc.
+   Contributed by Ollie Wild <aaw@google.com>.  */
+
+/* { dg-do preprocess } */
+/* { dg-options "-fdirectives-only -Wunused-macros" } */
+/* { dg-error "-fdirectives-only is incompatible with -Wunused_macros\n" "-Wunused-macros check" { target *-*-* } 0 } */
diff --git a/gcc/testsuite/gcc.dg/cpp/dir-only-5.c b/gcc/testsuite/gcc.dg/cpp/dir-only-5.c
new file mode 100644
index 0000000..643a4d7
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/cpp/dir-only-5.c
@@ -0,0 +1,6 @@
+/* Copyright 2007 Free Software Foundation, Inc.
+   Contributed by Ollie Wild <aaw@google.com>.  */
+
+/* { dg-do preprocess } */
+/* { dg-options "-fdirectives-only -traditional" } */
+/* { dg-error "-fdirectives-only is incompatible with -traditional\n" "-traditional check" { target *-*-* } 0 } */
diff --git a/gcc/testsuite/gcc.dg/cpp/dir-only-6.c b/gcc/testsuite/gcc.dg/cpp/dir-only-6.c
new file mode 100644
index 0000000..0023205
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/cpp/dir-only-6.c
@@ -0,0 +1,7 @@
+/* Copyright 2007 Free Software Foundation, Inc.
+   Contributed by Ollie Wild <aaw@google.com>.  */
+
+/* { dg-do preprocess } */
+/* { dg-options -fdirectives-only } */
+
+/* { dg-error "unterminated comment" }