PR c/81544 - attribute noreturn and warn_unused_result on the same function accepted
[official-gcc.git] / gcc / cp / g++spec.c
blobffcc87c79c9df760b939c7dc1ba3e6181c67e3c6
1 /* Specific flags and argument handling of the C++ front end.
2 Copyright (C) 1996-2017 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 3, or (at your option)
9 any later version.
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 COPYING3. If not see
18 <http://www.gnu.org/licenses/>. */
20 #include "config.h"
21 #include "system.h"
22 #include "coretypes.h"
23 #include "tm.h"
24 #include "opts.h"
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 `-lrt' or equivalent. */
31 #define TIMELIB (1<<3)
32 /* This bit is set if they did `-lc'. */
33 #define WITHLIBC (1<<4)
34 /* Skip this option. */
35 #define SKIPOPT (1<<5)
37 #ifndef MATH_LIBRARY
38 #define MATH_LIBRARY "m"
39 #endif
40 #ifndef MATH_LIBRARY_PROFILE
41 #define MATH_LIBRARY_PROFILE MATH_LIBRARY
42 #endif
44 #ifndef TIME_LIBRARY
45 #define TIME_LIBRARY ""
46 #endif
48 #ifndef LIBSTDCXX
49 #define LIBSTDCXX "stdc++"
50 #endif
51 #ifndef LIBSTDCXX_PROFILE
52 #define LIBSTDCXX_PROFILE LIBSTDCXX
53 #endif
54 #ifndef LIBSTDCXX_STATIC
55 #define LIBSTDCXX_STATIC NULL
56 #endif
58 void
59 lang_specific_driver (struct cl_decoded_option **in_decoded_options,
60 unsigned int *in_decoded_options_count,
61 int *in_added_libraries)
63 unsigned int i, j;
65 /* If nonzero, the user gave us the `-p' or `-pg' flag. */
66 int saw_profile_flag = 0;
68 /* What do with libstdc++:
69 -1 means we should not link in libstdc++
70 0 means we should link in libstdc++ if it is needed
71 1 means libstdc++ is needed and should be linked in.
72 2 means libstdc++ is needed and should be linked statically. */
73 int library = 0;
75 /* The number of arguments being added to what's in argv, other than
76 libraries. We use this to track the number of times we've inserted
77 -xc++/-xnone. */
78 int added = 0;
80 /* The new argument list will be contained in this. */
81 struct cl_decoded_option *new_decoded_options;
83 /* Nonzero if we saw a `-xfoo' language specification on the
84 command line. Used to avoid adding our own -xc++ if the user
85 already gave a language for the file. */
86 int saw_speclang = 0;
88 /* "-lm" or "-lmath" if it appears on the command line. */
89 const struct cl_decoded_option *saw_math = NULL;
91 /* "-lrt" or eqivalent if it appears on the command line. */
92 const struct cl_decoded_option *saw_time = NULL;
94 /* "-lc" if it appears on the command line. */
95 const struct cl_decoded_option *saw_libc = NULL;
97 /* An array used to flag each argument that needs a bit set for
98 LANGSPEC, MATHLIB, TIMELIB, or WITHLIBC. */
99 int *args;
101 /* By default, we throw on the math library if we have one. */
102 int need_math = (MATH_LIBRARY[0] != '\0');
104 /* By default, we throw on the time library if we have one. */
105 int need_time = (TIME_LIBRARY[0] != '\0');
107 /* True if we saw -static. */
108 int static_link = 0;
110 /* True if we should add -shared-libgcc to the command-line. */
111 int shared_libgcc = 1;
113 /* The total number of arguments with the new stuff. */
114 unsigned int argc;
116 /* The argument list. */
117 struct cl_decoded_option *decoded_options;
119 /* The number of libraries added in. */
120 int added_libraries;
122 /* The total number of arguments with the new stuff. */
123 unsigned int num_args = 1;
125 argc = *in_decoded_options_count;
126 decoded_options = *in_decoded_options;
127 added_libraries = *in_added_libraries;
129 args = XCNEWVEC (int, argc);
131 for (i = 1; i < argc; i++)
133 const char *arg = decoded_options[i].arg;
134 if (decoded_options[i].errors & CL_ERR_MISSING_ARG)
135 continue; /* Avoid examining arguments of options missing them. */
137 switch (decoded_options[i].opt_index)
139 case OPT_nostdlib:
140 case OPT_nodefaultlibs:
141 library = -1;
142 break;
144 case OPT_l:
145 if (strcmp (arg, MATH_LIBRARY) == 0)
147 args[i] |= MATHLIB;
148 need_math = 0;
150 else if (strcmp (arg, TIME_LIBRARY) == 0)
152 args[i] |= TIMELIB;
153 need_time = 0;
155 else if (strcmp (arg, "c") == 0)
156 args[i] |= WITHLIBC;
157 else
158 /* Unrecognized libraries (e.g. -lfoo) may require libstdc++. */
159 library = (library == 0) ? 1 : library;
160 break;
162 case OPT_pg:
163 case OPT_p:
164 saw_profile_flag++;
165 break;
167 case OPT_x:
168 if (library == 0
169 && (strcmp (arg, "c++") == 0
170 || strcmp (arg, "c++-cpp-output") == 0
171 || strcmp (arg, "objective-c++") == 0
172 || strcmp (arg, "objective-c++-cpp-output") == 0))
173 library = 1;
175 saw_speclang = 1;
176 break;
178 case OPT_Xlinker:
179 case OPT_Wl_:
180 /* Arguments that go directly to the linker might be .o files,
181 or something, and so might cause libstdc++ to be needed. */
182 if (library == 0)
183 library = 1;
184 break;
186 case OPT_c:
187 case OPT_S:
188 case OPT_E:
189 case OPT_M:
190 case OPT_MM:
191 case OPT_fsyntax_only:
192 /* Don't specify libraries if we won't link, since that would
193 cause a warning. */
194 library = -1;
195 break;
197 case OPT_static:
198 static_link = 1;
199 break;
201 case OPT_static_libgcc:
202 shared_libgcc = 0;
203 break;
205 case OPT_static_libstdc__:
206 library = library >= 0 ? 2 : library;
207 args[i] |= SKIPOPT;
208 break;
210 case OPT_SPECIAL_input_file:
212 int len;
214 /* We don't do this anymore, since we don't get them with minus
215 signs on them. */
216 if (arg[0] == '\0' || arg[1] == '\0')
217 continue;
219 if (saw_speclang)
221 saw_speclang = 0;
222 continue;
225 /* If the filename ends in .[chi], put options around it.
226 But not if a specified -x option is currently active. */
227 len = strlen (arg);
228 if (len > 2
229 && (arg[len - 1] == 'c'
230 || arg[len - 1] == 'i'
231 || arg[len - 1] == 'h')
232 && arg[len - 2] == '.')
234 args[i] |= LANGSPEC;
235 added += 2;
238 /* If we don't know that this is a header file, we might
239 need to be linking in the libraries. */
240 if (library == 0)
242 if ((len <= 2 || strcmp (arg + (len - 2), ".H") != 0)
243 && (len <= 2 || strcmp (arg + (len - 2), ".h") != 0)
244 && (len <= 4 || strcmp (arg + (len - 4), ".hpp") != 0)
245 && (len <= 3 || strcmp (arg + (len - 3), ".hp") != 0)
246 && (len <= 4 || strcmp (arg + (len - 4), ".hxx") != 0)
247 && (len <= 4 || strcmp (arg + (len - 4), ".h++") != 0)
248 && (len <= 4 || strcmp (arg + (len - 4), ".HPP") != 0)
249 && (len <= 4 || strcmp (arg + (len - 4), ".tcc") != 0)
250 && (len <= 3 || strcmp (arg + (len - 3), ".hh") != 0))
251 library = 1;
254 break;
258 /* There's no point adding -shared-libgcc if we don't have a shared
259 libgcc. */
260 #ifndef ENABLE_SHARED_LIBGCC
261 shared_libgcc = 0;
262 #endif
264 /* Add one for shared_libgcc or extra static library. */
265 num_args = argc + added + need_math + (library > 0) * 4 + 1;
266 new_decoded_options = XNEWVEC (struct cl_decoded_option, num_args);
268 i = 0;
269 j = 0;
271 /* Copy the 0th argument, i.e., the name of the program itself. */
272 new_decoded_options[j++] = decoded_options[i++];
274 /* NOTE: We start at 1 now, not 0. */
275 while (i < argc)
277 new_decoded_options[j] = decoded_options[i];
279 /* Make sure -lstdc++ is before the math library, since libstdc++
280 itself uses those math routines. */
281 if (!saw_math && (args[i] & MATHLIB) && library > 0)
283 --j;
284 saw_math = &decoded_options[i];
287 if (!saw_time && (args[i] & TIMELIB) && library > 0)
289 --j;
290 saw_time = &decoded_options[i];
293 if (!saw_libc && (args[i] & WITHLIBC) && library > 0)
295 --j;
296 saw_libc = &decoded_options[i];
299 /* Wrap foo.[chi] files in a language specification to
300 force the gcc compiler driver to run cc1plus on them. */
301 if (args[i] & LANGSPEC)
303 const char *arg = decoded_options[i].arg;
304 int len = strlen (arg);
305 switch (arg[len - 1])
307 case 'c':
308 generate_option (OPT_x, "c++", 1, CL_DRIVER,
309 &new_decoded_options[j++]);
310 break;
311 case 'i':
312 generate_option (OPT_x, "c++-cpp-output", 1, CL_DRIVER,
313 &new_decoded_options[j++]);
314 break;
315 case 'h':
316 generate_option (OPT_x, "c++-header", 1, CL_DRIVER,
317 &new_decoded_options[j++]);
318 break;
319 default:
320 gcc_unreachable ();
322 new_decoded_options[j++] = decoded_options[i];
323 generate_option (OPT_x, "none", 1, CL_DRIVER,
324 &new_decoded_options[j]);
327 if ((args[i] & SKIPOPT) != 0)
328 --j;
330 i++;
331 j++;
334 /* Add `-lstdc++' if we haven't already done so. */
335 if (library > 0)
337 #ifdef HAVE_LD_STATIC_DYNAMIC
338 if (library > 1 && !static_link)
340 generate_option (OPT_Wl_, LD_STATIC_OPTION, 1, CL_DRIVER,
341 &new_decoded_options[j]);
342 j++;
344 #endif
345 generate_option (OPT_l,
346 saw_profile_flag ? LIBSTDCXX_PROFILE : LIBSTDCXX, 1,
347 CL_DRIVER, &new_decoded_options[j]);
348 added_libraries++;
349 j++;
350 /* Add target-dependent static library, if necessary. */
351 if ((static_link || library > 1) && LIBSTDCXX_STATIC != NULL)
353 generate_option (OPT_l, LIBSTDCXX_STATIC, 1,
354 CL_DRIVER, &new_decoded_options[j]);
355 added_libraries++;
356 j++;
358 #ifdef HAVE_LD_STATIC_DYNAMIC
359 if (library > 1 && !static_link)
361 generate_option (OPT_Wl_, LD_DYNAMIC_OPTION, 1, CL_DRIVER,
362 &new_decoded_options[j]);
363 j++;
365 #endif
367 if (saw_math)
368 new_decoded_options[j++] = *saw_math;
369 else if (library > 0 && need_math)
371 generate_option (OPT_l,
372 saw_profile_flag ? MATH_LIBRARY_PROFILE : MATH_LIBRARY,
373 1, CL_DRIVER, &new_decoded_options[j]);
374 added_libraries++;
375 j++;
377 if (saw_time)
378 new_decoded_options[j++] = *saw_time;
379 else if (library > 0 && need_time)
381 generate_option (OPT_l, TIME_LIBRARY, 1, CL_DRIVER,
382 &new_decoded_options[j]);
383 added_libraries++;
384 j++;
386 if (saw_libc)
387 new_decoded_options[j++] = *saw_libc;
388 if (shared_libgcc && !static_link)
389 generate_option (OPT_shared_libgcc, NULL, 1, CL_DRIVER,
390 &new_decoded_options[j++]);
392 *in_decoded_options_count = j;
393 *in_decoded_options = new_decoded_options;
394 *in_added_libraries = added_libraries;
397 /* Called before linking. Returns 0 on success and -1 on failure. */
398 int lang_specific_pre_link (void) /* Not used for C++. */
400 return 0;
403 /* Number of extra output files that lang_specific_pre_link may generate. */
404 int lang_specific_extra_outfiles = 0; /* Not used for C++. */