2004-06-21 Geoffrey Keating <geoffk@apple.com>

	* c-opts.c (c_common_handle_option): Handle -fpch-preprocess.
	* c-common.h (flag_pch_preprocess): Declare.
	(c_common_pch_pragma): Likewise.
	* c-common.c (flag_pch_preprocess): New.
	* c-pch.c (c_common_read_pch): Support -fpreprocess-only.
	(c_common_pch_pragma): New.
	* c-ppoutput.c (cb_read_pch): New.
	(init_pp_output): Support -fpch-preprocess.
	* c-pragma.c (init_pragma): Support #pragma GNUC pch_preprocess.
	* c.opt (fpch-preprocess): New.
	* gcc.c (cpp_options): When save-temps, pass -fpch-preprocess.
	* doc/cppopts.texi: Document -fpch-preprocess.
	* doc/invoke.texi (Precompiled Headers): Mention that
	-fpreprocessed is safe for PCH.  Mention that if an option is
	listed as safe that doesn't mean it does what you expect.

Index: gcc/testsuite/ChangeLog
2004-06-21  Geoffrey Keating  <geoffk@apple.com>

	* gcc.dg/pch/save-temps-1.c: New file.
	* gcc.dg/pch/save-temps-1.hs: New file.

Index: libcpp/ChangeLog
2004-06-21  Geoffrey Keating  <geoffk@apple.com>

	* files.c (should_stack_file): Correct swapped parameters to call
	to cb.read_pch.
	* pch.c (cpp_valid_state): Handle -fpreprocessed.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@83478 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 66 insertions, 12 deletions

diff --git a/gcc/c-pch.c b/gcc/c-pch.c
index 03cf3bf08bc..eb043bd089e 100644
--- a/gcc/c-pch.c
+++ b/gcc/c-pch.c
@@ -393,8 +393,6 @@ c_common_read_pch (cpp_reader *pfile, const char *name,
 {
   FILE *f;
   struct c_pch_header h;
-  char *buf;
-  unsigned long written;
   struct save_macro_data *smd;
   
   f = fdopen (fd, "rb");
@@ -412,18 +410,30 @@ c_common_read_pch (cpp_reader *pfile, const char *name,
       return;
     }
 
-  buf = xmalloc (16384);
-  for (written = 0; written < h.asm_size; )
+  if (!flag_preprocess_only)
     {
-      long size = h.asm_size - written;
-      if (size > 16384)
-	size = 16384;
-      if (fread (buf, size, 1, f) != 1
-	  || fwrite (buf, size, 1, asm_out_file) != 1)
-	cpp_errno (pfile, CPP_DL_ERROR, "reading");
-      written += size;
+      unsigned long written;
+      char * buf = xmalloc (16384);
+
+      for (written = 0; written < h.asm_size; )
+	{
+	  long size = h.asm_size - written;
+	  if (size > 16384)
+	    size = 16384;
+	  if (fread (buf, size, 1, f) != 1
+	      || fwrite (buf, size, 1, asm_out_file) != 1)
+	    cpp_errno (pfile, CPP_DL_ERROR, "reading");
+	  written += size;
+	}
+      free (buf);
+    }
+  else
+    {
+      /* If we're preprocessing, don't write to a NULL
+	 asm_out_file.  */
+      if (fseek (f, h.asm_size, SEEK_CUR) != 0)
+	cpp_errno (pfile, CPP_DL_ERROR, "seeking");
     }
-  free (buf);
 
   cpp_prepare_state (pfile, &smd);
 
@@ -446,3 +456,47 @@ c_common_no_more_pch (void)
       host_hooks.gt_pch_use_address (NULL, 0, -1, 0);
     }
 }
+
+/* Handle #pragma GCC pch_preprocess, to load in the PCH file.  */
+
+#ifndef O_BINARY
+# define O_BINARY 0
+#endif
+
+void
+c_common_pch_pragma (cpp_reader *pfile)
+{
+  tree name_t;
+  const char *name;
+  int fd;
+
+  if (c_lex (&name_t) != CPP_STRING)
+    {
+      error ("malformed #pragma GCC pch_preprocess, ignored");
+      return;
+    }
+
+  if (! cpp_get_options (pfile)->preprocessed)
+    {
+      error ("pch_preprocess pragma should only be used with -fpreprocessed");
+      inform ("use #include instead");
+      return;
+    }
+
+  name = TREE_STRING_POINTER (name_t);
+  
+  fd = open (name, O_RDONLY | O_BINARY, 0666);
+  if (fd == -1)
+    fatal_error ("%s: couldn't open PCH file: %m\n", name);
+  
+  if (c_common_valid_pch (pfile, name, fd) != 1)
+    {
+      if (!cpp_get_options (pfile)->warn_invalid_pch)
+	inform ("use -Winvalid-pch for more information");
+      fatal_error ("%s: PCH file was invalid", name);
+    }
+  
+  c_common_read_pch (pfile, name, fd, name);
+  
+  close (fd);
+}