g++spec.c: Don't add libraries needlessly if -fsyntax-only was given.
[gcc.git] / gcc / cp / g++spec.c
1 /* Specific flags and argument handling of the C++ front-end.
2 Copyright (C) 1996, 1997, 1998, 1999, 2000 Free Software Foundation, Inc.
3
4 This file is part of GNU CC.
5
6 GNU CC 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)
9 any later version.
10
11 GNU CC 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.
15
16 You should have received a copy of the GNU General Public License
17 along with GNU CC; see the file COPYING. If not, write to
18 the Free Software Foundation, 59 Temple Place - Suite 330,
19 Boston, MA 02111-1307, USA. */
20
21 #include "config.h"
22 #include "system.h"
23 #include "gcc.h"
24
25 /* This bit is set if we saw a `-xfoo' language specification. */
26 #define LANGSPEC (1<<1)
27 /* This bit is set if they did `-lm' or `-lmath'. */
28 #define MATHLIB (1<<2)
29 /* This bit is set if they did `-lc'. */
30 #define WITHLIBC (1<<3)
31
32 #ifndef MATH_LIBRARY
33 #define MATH_LIBRARY "-lm"
34 #endif
35
36 #ifndef LIBSTDCXX
37 #define LIBSTDCXX "-lstdc++"
38 #endif
39
40 void
41 lang_specific_driver (in_argc, in_argv, in_added_libraries)
42 int *in_argc;
43 const char *const **in_argv;
44 int *in_added_libraries;
45 {
46 int i, j;
47
48 /* If non-zero, the user gave us the `-v' flag. */
49 int saw_verbose_flag = 0;
50
51 /* This will be 0 if we encounter a situation where we should not
52 link in libstdc++. */
53 int library = 1;
54
55 /* The number of arguments being added to what's in argv, other than
56 libraries. We use this to track the number of times we've inserted
57 -xc++/-xnone. */
58 int added = 2;
59
60 /* Used to track options that take arguments, so we don't go wrapping
61 those with -xc++/-xnone. */
62 const char *quote = NULL;
63
64 /* The new argument list will be contained in this. */
65 const char **arglist;
66
67 /* Non-zero if we saw a `-xfoo' language specification on the
68 command line. Used to avoid adding our own -xc++ if the user
69 already gave a language for the file. */
70 int saw_speclang = 0;
71
72 /* "-lm" or "-lmath" if it appears on the command line. */
73 const char *saw_math = 0;
74
75 /* "-lc" if it appears on the command line. */
76 const char *saw_libc = 0;
77
78 /* An array used to flag each argument that needs a bit set for
79 LANGSPEC, MATHLIB, or WITHLIBC. */
80 int *args;
81
82 /* By default, we throw on the math library if we have one. */
83 int need_math = (MATH_LIBRARY[0] != '\0');
84
85 /* The total number of arguments with the new stuff. */
86 int argc;
87
88 /* The argument list. */
89 const char *const *argv;
90
91 /* The number of libraries added in. */
92 int added_libraries;
93
94 /* The total number of arguments with the new stuff. */
95 int num_args = 1;
96
97 #if ENABLE_NEW_GXX_ABI
98 added++;
99 #endif
100
101 argc = *in_argc;
102 argv = *in_argv;
103 added_libraries = *in_added_libraries;
104
105 args = (int *) xcalloc (argc, sizeof (int));
106
107 for (i = 1; i < argc; i++)
108 {
109 /* If the previous option took an argument, we swallow it here. */
110 if (quote)
111 {
112 quote = NULL;
113 continue;
114 }
115
116 /* We don't do this anymore, since we don't get them with minus
117 signs on them. */
118 if (argv[i][0] == '\0' || argv[i][1] == '\0')
119 continue;
120
121 if (argv[i][0] == '-')
122 {
123 if (library != 0 && (strcmp (argv[i], "-nostdlib") == 0
124 || strcmp (argv[i], "-nodefaultlibs") == 0))
125 {
126 library = 0;
127 }
128 else if (strcmp (argv[i], "-lm") == 0
129 || strcmp (argv[i], "-lmath") == 0
130 || strcmp (argv[i], MATH_LIBRARY) == 0
131 #ifdef ALT_LIBM
132 || strcmp (argv[i], ALT_LIBM) == 0
133 #endif
134 )
135 {
136 args[i] |= MATHLIB;
137 need_math = 0;
138 }
139 else if (strcmp (argv[i], "-lc") == 0)
140 args[i] |= WITHLIBC;
141 else if (strcmp (argv[i], "-v") == 0)
142 {
143 saw_verbose_flag = 1;
144 if (argc == 2)
145 {
146 /* If they only gave us `-v', don't try to link
147 in libg++. */
148 library = 0;
149 }
150 }
151 else if (strncmp (argv[i], "-x", 2) == 0)
152 saw_speclang = 1;
153 else if (((argv[i][2] == '\0'
154 && (char *)strchr ("bBVDUoeTuIYmLiA", argv[i][1]) != NULL)
155 || strcmp (argv[i], "-Tdata") == 0))
156 quote = argv[i];
157 else if (library != 0 && ((argv[i][2] == '\0'
158 && (char *) strchr ("cSEM", argv[i][1]) != NULL)
159 || strcmp (argv[i], "-MM") == 0
160 || strcmp (argv[i], "-fsyntax-only") == 0))
161 {
162 /* Don't specify libraries if we won't link, since that would
163 cause a warning. */
164 library = 0;
165 added -= 2;
166 }
167 else
168 /* Pass other options through. */
169 continue;
170 }
171 else
172 {
173 int len;
174
175 if (saw_speclang)
176 {
177 saw_speclang = 0;
178 continue;
179 }
180
181 /* If the filename ends in .c or .i, put options around it.
182 But not if a specified -x option is currently active. */
183 len = strlen (argv[i]);
184 if (len > 2
185 && (argv[i][len - 1] == 'c' || argv[i][len - 1] == 'i')
186 && argv[i][len - 2] == '.')
187 {
188 args[i] |= LANGSPEC;
189 added += 2;
190 }
191 }
192 }
193
194 if (quote)
195 fatal ("argument to `%s' missing\n", quote);
196
197 /* If we know we don't have to do anything, bail now. */
198 if (! added && ! library)
199 {
200 free (args);
201 return;
202 }
203
204 /* Make sure to have room for the trailing NULL argument. */
205 num_args = argc + added + need_math + 1;
206 arglist = (const char **) xmalloc (num_args * sizeof (char *));
207
208 i = 0;
209 j = 0;
210
211 /* Copy the 0th argument, i.e., the name of the program itself. */
212 arglist[i++] = argv[j++];
213
214 #if ENABLE_NEW_GXX_ABI
215 /* If we should use the new ABI by default, add the appropriate flag
216 to cc1plus here. We put this first so that it can be overridden
217 by other command-line options. */
218 arglist[j++] = "-fnew-abi";
219 #endif
220
221 /* NOTE: We start at 1 now, not 0. */
222 while (i < argc)
223 {
224 arglist[j] = argv[i];
225
226 /* Make sure -lstdc++ is before the math library, since libstdc++
227 itself uses those math routines. */
228 if (!saw_math && (args[i] & MATHLIB) && library)
229 {
230 --j;
231 saw_math = argv[i];
232 }
233
234 if (!saw_libc && (args[i] & WITHLIBC) && library)
235 {
236 --j;
237 saw_libc = argv[i];
238 }
239
240 /* Wrap foo.c and foo.i files in a language specification to
241 force the gcc compiler driver to run cc1plus on them. */
242 if (args[i] & LANGSPEC)
243 {
244 int len = strlen (argv[i]);
245 if (argv[i][len - 1] == 'i')
246 arglist[j++] = "-xc++-cpp-output";
247 else
248 arglist[j++] = "-xc++";
249 arglist[j++] = argv[i];
250 arglist[j] = "-xnone";
251 }
252
253 i++;
254 j++;
255 }
256
257 /* Add `-lstdc++' if we haven't already done so. */
258 if (library)
259 {
260 arglist[j++] = LIBSTDCXX;
261 added_libraries++;
262 }
263 if (saw_math)
264 arglist[j++] = saw_math;
265 else if (library && need_math)
266 {
267 arglist[j++] = MATH_LIBRARY;
268 added_libraries++;
269 }
270 if (saw_libc)
271 arglist[j++] = saw_libc;
272
273 arglist[j] = NULL;
274
275 *in_argc = j;
276 *in_argv = arglist;
277 *in_added_libraries = added_libraries;
278 }
279
280 /* Called before linking. Returns 0 on success and -1 on failure. */
281 int lang_specific_pre_link () /* Not used for C++. */
282 {
283 return 0;
284 }
285
286 /* Number of extra output files that lang_specific_pre_link may generate. */
287 int lang_specific_extra_outfiles = 0; /* Not used for C++. */