cppfiles.c (stack_include_file): Don't optimize zero-length files.

	* cppfiles.c (stack_include_file): Don't optimize zero-length
	files.
	(read_include_file): NUL-terminate read files.
	* cpplex.c (handle_newline, skip_escaped_newlines,
	get_effective_char, skip_whitespace, parse_identifier,
	parse_identifier_slow, parse_number, parse_string,
	_cpp_lex_direct): Optimize for the fact that buffers are guaranteed
	NUL-terminated.
	* cpplib.c (destringize_and_run, cpp_define, handle_assertion):
	Be sure buffers are NUL terminated.
	* cppmacro.c (warn_of_redefinition): Kill compile warning.

	* c-common.c: Include tree-inline.h.
	(c_language): Move separate definitions here.
	(c_common_init_options, c_common_post_options): New.
	(c_common_lang_init): Rename c_common_init.
	* c-common.h (c_common_lang_init): Similarly.
	(c_common_init_options, c_common_post_options): New.
	* c-lang.c (c_post_options): Move body to c_common_post_options.
	(c_init_options): Use c_common_init_options.
	(c_init): Update.
	* langhooks.def: Rearrange.
	* langhooks.h: Rearrange, and improve comments.
	* toplev.c (do_compile): New function.
	(toplev_main): Use it.
	(lang_independent_f_options, parse_options_and_default_flags,
	process_options): Remove trailing periods.
	* Makefile.in: Update.
cp:	* decl2.c (c_language): Move to c-common.c.
	* lex.c (cxx_post_options, cxx_init_options): Use c-common.c
	functions.
	(cxx_init): Update.
objc:	* objc-act.c (objc_post_options, objc_init_options): Use c-common.c
	functions.
	(ojbc_init): Update.

From-SVN: r47362

1 files changed, 21 insertions, 12 deletions

diff --git a/gcc/cppfiles.c b/gcc/cppfiles.c
index 1fb357d..f0d85d9 100644
--- a/gcc/cppfiles.c
+++ b/gcc/cppfiles.c
@@ -296,17 +296,17 @@ stack_include_file (pfile, inc)
   /* Not in cache?  */
   if (! inc->buffer)
     {
-      /* Mark a regular, zero-length file never-reread.  Zero-length
-	 files are stacked the first time, so preprocessing a main
-	 file of zero length does not raise an error.  */
-      if (S_ISREG (inc->st.st_mode) && inc->st.st_size == 0)
-	_cpp_never_reread (inc);
-      else if (read_include_file (pfile, inc))
+      if (read_include_file (pfile, inc))
 	{
 	  /* If an error occurs, do not try to read this file again.  */
 	  _cpp_never_reread (inc);
 	  return false;
 	}
+      /* Mark a regular, zero-length file never-reread.  We read it,
+	 NUL-terminate it, and stack it once, so preprocessing a main
+	 file of zero length does not raise an error.  */
+      if (S_ISREG (inc->st.st_mode) && inc->st.st_size == 0)
+	_cpp_never_reread (inc);
       close (inc->fd);
       inc->fd = -1;
     }
@@ -382,7 +382,8 @@ read_include_file (pfile, inc)
       if (pagesize == -1)
 	pagesize = getpagesize ();
 
-      if (size / pagesize >= MMAP_THRESHOLD)
+      if (size / pagesize >= MMAP_THRESHOLD
+	  && (size % pagesize) != 0)
 	{
 	  buf = (U_CHAR *) mmap (0, size, PROT_READ, MAP_PRIVATE, inc->fd, 0);
 	  if (buf == (U_CHAR *)-1)
@@ -392,7 +393,7 @@ read_include_file (pfile, inc)
       else
 #endif
 	{
-	  buf = (U_CHAR *) xmalloc (size);
+	  buf = (U_CHAR *) xmalloc (size + 1);
 	  offset = 0;
 	  while (offset < size)
 	    {
@@ -410,6 +411,8 @@ read_include_file (pfile, inc)
 		}
 	      offset += count;
 	    }
+	  /* The lexer requires that the buffer be NUL-terminated.  */
+	  buf[size] = '\0';
 	}
     }
   else if (S_ISBLK (inc->st.st_mode))
@@ -424,19 +427,25 @@ read_include_file (pfile, inc)
 	 bigger than the majority of C source files.  */
       size = 8 * 1024;
 
-      buf = (U_CHAR *) xmalloc (size);
+      buf = (U_CHAR *) xmalloc (size + 1);
       offset = 0;
       while ((count = read (inc->fd, buf + offset, size - offset)) > 0)
 	{
 	  offset += count;
 	  if (offset == size)
-	    buf = xrealloc (buf, (size *= 2));
+	    {
+	      size *= 2;
+	      buf = xrealloc (buf, size + 1);
+	    }
 	}
       if (count < 0)
 	goto perror_fail;
 
-      if (offset < size)
-	buf = xrealloc (buf, offset);
+      if (offset + 1 < size)
+	buf = xrealloc (buf, offset + 1);
+
+      /* The lexer requires that the buffer be NUL-terminated.  */
+      buf[offset] = '\0';
       inc->st.st_size = offset;
     }