1 /* Specific flags and argument handling of the C++ front end.
2 Copyright (C) 1996-2022 Free Software Foundation, Inc.
3
4 This file is part of GCC.
5
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 3, or (at your option)
9 any later version.
10
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.
15
16 You should have received a copy of the GNU General Public License
17 along with GCC; see the file COPYING3. If not see
18 <http://www.gnu.org/licenses/>. */
19
20 #include "config.h"
21 #include "system.h"
22 #include "coretypes.h"
23 #include "tm.h"
24 #include "opts.h"
25
26 /* This bit is set if we saw a `-xfoo' language specification. */
27 #define LANGSPEC (1<<1)
28 /* This bit is set if they did `-lm' or `-lmath'. */
29 #define MATHLIB (1<<2)
30 /* This bit is set if they did `-lc'. */
31 #define WITHLIBC (1<<3)
32 /* Skip this option. */
33 #define SKIPOPT (1<<4)
34
35 #ifndef MATH_LIBRARY
36 #define MATH_LIBRARY "m"
37 #endif
38 #ifndef MATH_LIBRARY_PROFILE
39 #define MATH_LIBRARY_PROFILE MATH_LIBRARY
40 #endif
41
42 #ifndef LIBSTDCXX
43 #define LIBSTDCXX "stdc++"
44 #endif
45 #ifndef LIBSTDCXX_PROFILE
46 #define LIBSTDCXX_PROFILE LIBSTDCXX
47 #endif
48 #ifndef LIBSTDCXX_STATIC
49 #define LIBSTDCXX_STATIC NULL
50 #endif
51
52 #ifndef LIBCXX
53 #define LIBCXX "c++"
54 #endif
55 #ifndef LIBCXX_PROFILE
56 #define LIBCXX_PROFILE LIBCXX
57 #endif
58 #ifndef LIBCXX_STATIC
59 #define LIBCXX_STATIC NULL
60 #endif
61
62 #ifndef LIBCXXABI
63 #define LIBCXXABI "c++abi"
64 #endif
65 #ifndef LIBCXXABI_PROFILE
66 #define LIBCXXABI_PROFILE LIBCXXABI
67 #endif
68 #ifndef LIBCXXABI_STATIC
69 #define LIBCXXABI_STATIC NULL
70 #endif
71
72 /* The values used here must match those of the stdlib_kind enumeration
73 in c.opt. */
74 enum stdcxxlib_kind
75 {
76 USE_LIBSTDCXX = 1,
77 USE_LIBCXX = 2
78 };
79
80 void
lang_specific_driver(struct cl_decoded_option ** in_decoded_options,unsigned int * in_decoded_options_count,int * in_added_libraries)81 lang_specific_driver (struct cl_decoded_option **in_decoded_options,
82 unsigned int *in_decoded_options_count,
83 int *in_added_libraries)
84 {
85 unsigned int i, j;
86
87 /* If nonzero, the user gave us the `-p' or `-pg' flag. */
88 int saw_profile_flag = 0;
89
90 /* What action to take for the c++ runtime library:
91 -1 means we should not link it in.
92 0 means we should link it if it is needed.
93 1 means it is needed and should be linked in.
94 2 means it is needed but should be linked statically. */
95 int library = 0;
96
97 /* Which c++ runtime library to link. */
98 stdcxxlib_kind which_library = USE_LIBSTDCXX;
99
100 /* The number of arguments being added to what's in argv, other than
101 libraries. We use this to track the number of times we've inserted
102 -xc++/-xnone. */
103 int added = 0;
104
105 /* The new argument list will be contained in this. */
106 struct cl_decoded_option *new_decoded_options;
107
108 /* Nonzero if we saw a `-xfoo' language specification on the
109 command line. Used to avoid adding our own -xc++ if the user
110 already gave a language for the file. */
111 int saw_speclang = 0;
112
113 /* "-lm" or "-lmath" if it appears on the command line. */
114 const struct cl_decoded_option *saw_math = NULL;
115
116 /* "-lrt" or eqivalent if it appears on the command line. */
117 const struct cl_decoded_option *saw_time = NULL;
118
119 /* "-lc" if it appears on the command line. */
120 const struct cl_decoded_option *saw_libc = NULL;
121
122 /* An array used to flag each argument that needs a bit set for
123 LANGSPEC, MATHLIB, or WITHLIBC. */
124 int *args;
125
126 /* By default, we throw on the math library if we have one. */
127 int need_math = (MATH_LIBRARY[0] != '\0');
128
129 /* True if we saw -static. */
130 int static_link = 0;
131
132 /* True if we should add -shared-libgcc to the command-line. */
133 int shared_libgcc = 1;
134
135 /* The total number of arguments with the new stuff. */
136 unsigned int argc;
137
138 /* The argument list. */
139 struct cl_decoded_option *decoded_options;
140
141 /* The number of libraries added in. */
142 int added_libraries;
143
144 /* The total number of arguments with the new stuff. */
145 unsigned int num_args = 1;
146
147 argc = *in_decoded_options_count;
148 decoded_options = *in_decoded_options;
149 added_libraries = *in_added_libraries;
150
151 args = XCNEWVEC (int, argc);
152
153 for (i = 1; i < argc; i++)
154 {
155 const char *arg = decoded_options[i].arg;
156 if (decoded_options[i].errors & CL_ERR_MISSING_ARG)
157 continue; /* Avoid examining arguments of options missing them. */
158
159 switch (decoded_options[i].opt_index)
160 {
161 case OPT_nostdlib:
162 case OPT_nodefaultlibs:
163 library = -1;
164 break;
165
166 case OPT_l:
167 if (strcmp (arg, MATH_LIBRARY) == 0)
168 {
169 args[i] |= MATHLIB;
170 need_math = 0;
171 }
172 else if (strcmp (arg, "c") == 0)
173 args[i] |= WITHLIBC;
174 else
175 /* Unrecognized libraries (e.g. -lfoo) may require libstdc++. */
176 library = (library == 0) ? 1 : library;
177 break;
178
179 case OPT_pg:
180 case OPT_p:
181 saw_profile_flag++;
182 break;
183
184 case OPT_x:
185 if (library == 0
186 && (strcmp (arg, "c++") == 0
187 || strcmp (arg, "c++-cpp-output") == 0
188 || strcmp (arg, "objective-c++") == 0
189 || strcmp (arg, "objective-c++-cpp-output") == 0))
190 library = 1;
191
192 saw_speclang = 1;
193 break;
194
195 case OPT_Xlinker:
196 case OPT_Wl_:
197 /* Arguments that go directly to the linker might be .o files,
198 or something, and so might cause libstdc++ to be needed. */
199 if (library == 0)
200 library = 1;
201 break;
202
203 case OPT_c:
204 case OPT_r:
205 case OPT_S:
206 case OPT_E:
207 case OPT_M:
208 case OPT_MM:
209 case OPT_fsyntax_only:
210 /* Don't specify libraries if we won't link, since that would
211 cause a warning. */
212 library = -1;
213 break;
214
215 case OPT_static:
216 static_link = 1;
217 break;
218
219 case OPT_static_libgcc:
220 shared_libgcc = 0;
221 break;
222
223 case OPT_static_libstdc__:
224 library = library >= 0 ? 2 : library;
225 #ifdef HAVE_LD_STATIC_DYNAMIC
226 /* Remove -static-libstdc++ from the command only if target supports
227 LD_STATIC_DYNAMIC. When not supported, it is left in so that a
228 back-end target can use outfile substitution. */
229 args[i] |= SKIPOPT;
230 #endif
231 break;
232
233 case OPT_stdlib_:
234 which_library = (stdcxxlib_kind) decoded_options[i].value;
235 break;
236
237 case OPT_SPECIAL_input_file:
238 {
239 int len;
240
241 /* We don't do this anymore, since we don't get them with minus
242 signs on them. */
243 if (arg[0] == '\0' || arg[1] == '\0')
244 continue;
245
246 if (saw_speclang)
247 {
248 saw_speclang = 0;
249 continue;
250 }
251
252 /* If the filename ends in .[chi], put options around it.
253 But not if a specified -x option is currently active. */
254 len = strlen (arg);
255 if (len > 2
256 && (arg[len - 1] == 'c'
257 || arg[len - 1] == 'i'
258 || arg[len - 1] == 'h')
259 && arg[len - 2] == '.')
260 {
261 args[i] |= LANGSPEC;
262 added += 2;
263 }
264
265 /* If we don't know that this is a header file, we might
266 need to be linking in the libraries. */
267 if (library == 0)
268 {
269 if ((len <= 2 || strcmp (arg + (len - 2), ".H") != 0)
270 && (len <= 2 || strcmp (arg + (len - 2), ".h") != 0)
271 && (len <= 4 || strcmp (arg + (len - 4), ".hpp") != 0)
272 && (len <= 3 || strcmp (arg + (len - 3), ".hp") != 0)
273 && (len <= 4 || strcmp (arg + (len - 4), ".hxx") != 0)
274 && (len <= 4 || strcmp (arg + (len - 4), ".h++") != 0)
275 && (len <= 4 || strcmp (arg + (len - 4), ".HPP") != 0)
276 && (len <= 4 || strcmp (arg + (len - 4), ".tcc") != 0)
277 && (len <= 3 || strcmp (arg + (len - 3), ".hh") != 0))
278 library = 1;
279 }
280 }
281 break;
282 }
283 }
284
285 /* There's no point adding -shared-libgcc if we don't have a shared
286 libgcc. */
287 #ifndef ENABLE_SHARED_LIBGCC
288 shared_libgcc = 0;
289 #endif
290
291 /* Add one for shared_libgcc or extra static library. */
292 num_args = argc + added + need_math + (library > 0) * 4 + 1;
293 /* For libc++, on most platforms, the ABI library (usually called libc++abi)
294 is provided as a separate DSO, which we must also append.
295 However, a platform might have the ability to forward the ABI library
296 from libc++, or combine it in some other way; in that case, LIBCXXABI
297 should be set to NULL to signal that it need not be appended. */
298 if (which_library == USE_LIBCXX && LIBCXXABI != NULL)
299 num_args += 4;
300 new_decoded_options = XNEWVEC (struct cl_decoded_option, num_args);
301
302 i = 0;
303 j = 0;
304
305 /* Copy the 0th argument, i.e., the name of the program itself. */
306 new_decoded_options[j++] = decoded_options[i++];
307
308 /* NOTE: We start at 1 now, not 0. */
309 while (i < argc)
310 {
311 new_decoded_options[j] = decoded_options[i];
312
313 /* Make sure -lstdc++ is before the math library, since libstdc++
314 itself uses those math routines. */
315 if (!saw_math && (args[i] & MATHLIB) && library > 0)
316 {
317 --j;
318 saw_math = &decoded_options[i];
319 }
320
321 if (!saw_libc && (args[i] & WITHLIBC) && library > 0)
322 {
323 --j;
324 saw_libc = &decoded_options[i];
325 }
326
327 /* Wrap foo.[chi] files in a language specification to
328 force the gcc compiler driver to run cc1plus on them. */
329 if (args[i] & LANGSPEC)
330 {
331 const char *arg = decoded_options[i].arg;
332 int len = strlen (arg);
333 switch (arg[len - 1])
334 {
335 case 'c':
336 generate_option (OPT_x, "c++", 1, CL_DRIVER,
337 &new_decoded_options[j++]);
338 break;
339 case 'i':
340 generate_option (OPT_x, "c++-cpp-output", 1, CL_DRIVER,
341 &new_decoded_options[j++]);
342 break;
343 case 'h':
344 generate_option (OPT_x, "c++-header", 1, CL_DRIVER,
345 &new_decoded_options[j++]);
346 break;
347 default:
348 gcc_unreachable ();
349 }
350 new_decoded_options[j++] = decoded_options[i];
351 generate_option (OPT_x, "none", 1, CL_DRIVER,
352 &new_decoded_options[j]);
353 }
354
355 if ((args[i] & SKIPOPT) != 0)
356 --j;
357
358 i++;
359 j++;
360 }
361
362 /* Add `-lstdc++' if we haven't already done so. */
363 if (library > 0)
364 {
365 #ifdef HAVE_LD_STATIC_DYNAMIC
366 if (library > 1 && !static_link)
367 {
368 generate_option (OPT_Wl_, LD_STATIC_OPTION, 1, CL_DRIVER,
369 &new_decoded_options[j]);
370 j++;
371 }
372 #endif
373 if (which_library == USE_LIBCXX)
374 {
375 generate_option (OPT_l,
376 saw_profile_flag ? LIBCXX_PROFILE : LIBCXX, 1,
377 CL_DRIVER, &new_decoded_options[j]);
378 if (LIBCXXABI != NULL)
379 {
380 j++;
381 added_libraries++;
382 generate_option (OPT_l,
383 saw_profile_flag ? LIBCXXABI_PROFILE
384 : LIBCXXABI, 1,
385 CL_DRIVER, &new_decoded_options[j]);
386 }
387 }
388 else
389 generate_option (OPT_l,
390 saw_profile_flag ? LIBSTDCXX_PROFILE : LIBSTDCXX, 1,
391 CL_DRIVER, &new_decoded_options[j]);
392 added_libraries++;
393 j++;
394 /* Add target-dependent static library, if necessary. */
395 if ((static_link || library > 1) && LIBSTDCXX_STATIC != NULL)
396 {
397 generate_option (OPT_l, LIBSTDCXX_STATIC, 1,
398 CL_DRIVER, &new_decoded_options[j]);
399 added_libraries++;
400 j++;
401 }
402 #ifdef HAVE_LD_STATIC_DYNAMIC
403 if (library > 1 && !static_link)
404 {
405 generate_option (OPT_Wl_, LD_DYNAMIC_OPTION, 1, CL_DRIVER,
406 &new_decoded_options[j]);
407 j++;
408 }
409 #endif
410 }
411 if (saw_math)
412 new_decoded_options[j++] = *saw_math;
413 else if (library > 0 && need_math)
414 {
415 generate_option (OPT_l,
416 saw_profile_flag ? MATH_LIBRARY_PROFILE : MATH_LIBRARY,
417 1, CL_DRIVER, &new_decoded_options[j]);
418 added_libraries++;
419 j++;
420 }
421 if (saw_time)
422 new_decoded_options[j++] = *saw_time;
423 if (saw_libc)
424 new_decoded_options[j++] = *saw_libc;
425 if (shared_libgcc && !static_link)
426 generate_option (OPT_shared_libgcc, NULL, 1, CL_DRIVER,
427 &new_decoded_options[j++]);
428
429 *in_decoded_options_count = j;
430 *in_decoded_options = new_decoded_options;
431 *in_added_libraries = added_libraries;
432 }
433
434 /* Called before linking. Returns 0 on success and -1 on failure. */
lang_specific_pre_link(void)435 int lang_specific_pre_link (void) /* Not used for C++. */
436 {
437 return 0;
438 }
439
440 /* Number of extra output files that lang_specific_pre_link may generate. */
441 int lang_specific_extra_outfiles = 0; /* Not used for C++. */
442