1 /* Precompiled header implementation for the C languages.
2 Copyright (C) 2000, 2002 Free Software Foundation, Inc.
4 This file is part of GCC.
6 GCC is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2, or (at your option)
11 GCC is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with GCC; see the file COPYING. If not, write to
18 the Free Software Foundation, 59 Temple Place - Suite 330,
19 Boston, MA 02111-1307, USA. */
23 #include "coretypes.h"
33 #include "langhooks.h"
37 unsigned char debug_info_type;
42 unsigned long asm_size;
45 #define IDENT_LENGTH 8
47 static FILE *pch_outfile;
49 extern char *asm_file_name;
50 static long asm_file_startpos;
52 static const char * get_ident PARAMS((void));
54 /* Compute an appropriate 8-byte magic number for the PCH file, so that
55 utilities like file(1) can identify it, and so that GCC can quickly
56 ignore non-PCH files and PCH files that are of a completely different
62 static char result[IDENT_LENGTH];
63 static const char template[IDENT_LENGTH] = "gpch.011";
65 memcpy (result, template, IDENT_LENGTH);
66 if (c_language == clk_c)
67 result[4] = flag_objc ? 'o' : 'C';
68 else if (c_language == clk_cplusplus)
69 result[4] = flag_objc ? 'O' : '+';
75 /* Prepare to write a PCH file. This is called at the start of
82 struct c_pch_validity v;
87 f = fopen (pch_file, "w+b");
89 fatal_io_error ("can't open %s", pch_file);
92 v.debug_info_type = write_symbols;
93 if (fwrite (get_ident(), IDENT_LENGTH, 1, f) != 1
94 || fwrite (&v, sizeof (v), 1, f) != 1)
95 fatal_io_error ("can't write to %s", pch_file);
97 /* We need to be able to re-read the output. */
98 /* The driver always provides a valid -o option. */
99 if (asm_file_name == NULL
100 || strcmp (asm_file_name, "-") == 0)
101 fatal_error ("`%s' is not a valid output file", asm_file_name);
103 asm_file_startpos = ftell (asm_out_file);
105 /* Let the debugging format deal with the PCHness. */
106 (*debug_hooks->handle_pch) (0);
108 cpp_save_state (parse_in, f);
111 /* Write the PCH file. This is called at the end of a compilation which
112 will produce a PCH file. */
115 c_common_write_pch ()
120 struct c_pch_header h;
122 (*debug_hooks->handle_pch) (1);
124 cpp_write_pch_deps (parse_in, pch_outfile);
126 asm_file_end = ftell (asm_out_file);
127 h.asm_size = asm_file_end - asm_file_startpos;
129 if (fwrite (&h, sizeof (h), 1, pch_outfile) != 1)
130 fatal_io_error ("can't write %s", pch_file);
132 buf = xmalloc (16384);
133 fflush (asm_out_file);
135 if (fseek (asm_out_file, asm_file_startpos, SEEK_SET) != 0)
136 fatal_io_error ("can't seek in %s", asm_file_name);
138 for (written = asm_file_startpos; written < asm_file_end; )
140 long size = asm_file_end - written;
143 if (fread (buf, size, 1, asm_out_file) != 1)
144 fatal_io_error ("can't read %s", asm_file_name);
145 if (fwrite (buf, size, 1, pch_outfile) != 1)
146 fatal_io_error ("can't write %s", pch_file);
151 gt_pch_save (pch_outfile);
152 cpp_write_pch_state (parse_in, pch_outfile);
154 fclose (pch_outfile);
157 /* Check the PCH file called NAME, open on FD, to see if it can be used
158 in this compilation. */
161 c_common_valid_pch (pfile, name, fd)
168 char ident[IDENT_LENGTH];
169 const char *pch_ident;
170 struct c_pch_validity v;
175 /* Perform a quick test of whether this is a valid
176 precompiled header for the current language. */
178 sizeread = read (fd, ident, IDENT_LENGTH);
181 fatal_io_error ("can't read %s", name);
184 else if (sizeread != IDENT_LENGTH)
187 pch_ident = get_ident();
188 if (memcmp (ident, pch_ident, IDENT_LENGTH) != 0)
190 if (cpp_get_options (pfile)->warn_invalid_pch)
192 if (memcmp (ident, pch_ident, 5) == 0)
193 /* It's a PCH, for the right language, but has the wrong version.
195 cpp_error (pfile, DL_WARNING,
196 "%s: not compatible with this GCC version", name);
197 else if (memcmp (ident, pch_ident, 4) == 0)
198 /* It's a PCH for the wrong language. */
199 cpp_error (pfile, DL_WARNING, "%s: not for %s", name,
202 /* Not any kind of PCH. */
203 cpp_error (pfile, DL_WARNING, "%s: not a PCH file", name);
208 if (read (fd, &v, sizeof (v)) != sizeof (v))
210 fatal_io_error ("can't read %s", name);
214 /* The allowable debug info combinations are that either the PCH file
215 was built with the same as is being used now, or the PCH file was
216 built for some kind of debug info but now none is in use. */
217 if (v.debug_info_type != write_symbols
218 && write_symbols != NO_DEBUG)
220 if (cpp_get_options (pfile)->warn_invalid_pch)
221 cpp_error (pfile, DL_WARNING,
222 "%s: created with -g%s, but used with -g%s", name,
223 debug_type_names[v.debug_info_type],
224 debug_type_names[write_symbols]);
228 /* Check the preprocessor macros are the same as when the PCH was
231 result = cpp_valid_state (pfile, name, fd);
238 /* Load in the PCH file NAME, open on FD. It was originally searched for
242 c_common_read_pch (pfile, name, fd, orig_name)
246 const char *orig_name ATTRIBUTE_UNUSED;
249 struct c_pch_header h;
251 unsigned long written;
252 struct save_macro_data *smd;
254 f = fdopen (fd, "rb");
257 cpp_errno (pfile, DL_ERROR, "calling fdopen");
263 if (fread (&h, sizeof (h), 1, f) != 1)
265 cpp_errno (pfile, DL_ERROR, "reading");
269 buf = xmalloc (16384);
270 for (written = 0; written < h.asm_size; )
272 long size = h.asm_size - written;
275 if (fread (buf, size, 1, f) != 1
276 || fwrite (buf, size, 1, asm_out_file) != 1)
277 cpp_errno (pfile, DL_ERROR, "reading");
282 cpp_prepare_state (pfile, &smd);
286 if (cpp_read_state (pfile, name, f, smd) != 0)