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0e166a63 RP |
1 | .\" Copyright (c) 1991, 1992 Free Software Foundation |
2 | .\" See section COPYING for conditions for redistribution | |
3 | .TH ld 1 "17 August 1992" "cygnus support" "GNU Development Tools" | |
4 | .de BP | |
5 | .sp | |
6 | .ti \-.2i | |
7 | \(** | |
8 | .. | |
9 | ||
10 | .SH NAME | |
11 | ld \- the GNU linker | |
12 | ||
13 | .SH SYNOPSIS | |
14 | .hy 0 | |
15 | .na | |
16 | .TP | |
17 | .B ld | |
18 | .RB "[\|" \-o " | |
19 | .I output\c | |
20 | \&\|] \c | |
8ddef552 | 21 | .I objfile\c |
0e166a63 RP |
22 | \&.\|.\|. |
23 | .br | |
24 | .RB "[\|" \-A\c | |
25 | .I architecture\c | |
26 | \&\|] | |
27 | .RB "[\|" "\-b\ "\c | |
28 | .I input-format\c | |
29 | \&\|] | |
30 | .RB "[\|" \-Bstatic "\|]" | |
31 | .RB "[\|" "\-c\ "\c | |
32 | .I commandfile\c | |
33 | \&\|] | |
34 | .RB "[\|" \-d | \-dc | \-dp\c | |
35 | \|] | |
36 | .br | |
37 | .RB "[\|" "\-defsym\ "\c | |
38 | .I symbol\c | |
39 | \& = \c | |
40 | .I expression\c | |
41 | \&\|] | |
42 | .RB "[\|" "\-e\ "\c | |
43 | .I entry\c | |
44 | \&\|] | |
45 | .RB "[\|" \-F "\|]" | |
46 | .RB "[\|" "\-F\ "\c | |
47 | .I format\c | |
48 | \&\|] | |
49 | .RB "[\|" "\-format\ "\c | |
50 | .I input-format\c | |
51 | \&\|] | |
52 | .RB "[\|" \-g "\|]" | |
8ddef552 DM |
53 | .RB "[\|" \-G\c |
54 | .I size\c | |
55 | \&\|] | |
0e166a63 RP |
56 | .RB "[\|" \-i "\|]" |
57 | .RB "[\|" \-l\c | |
58 | .I ar\c | |
59 | \&\|] | |
60 | .RB "[\|" \-L\c | |
61 | .I searchdir\c | |
62 | \&\|] | |
8ddef552 | 63 | .RB "[\|" \-M "\|]" |
d18a4527 DM |
64 | .RB "[\|" \-Map\c |
65 | .I mapfile\c | |
66 | \&\|] | |
8ddef552 DM |
67 | .RB "[\|" \-m\c |
68 | .I emulation\c | |
69 | \&\|] | |
0e166a63 RP |
70 | .RB "[\|" \-n | \-N "\|]" |
71 | .RB "[\|" \-noinhibit-exec "\|]" | |
346535cc DM |
72 | .RB "[\|" "\-oformat\ "\c |
73 | .I output-format\c | |
74 | \&\|] | |
0e166a63 RP |
75 | .RB "[\|" "\-R\ "\c |
76 | .I filename\c | |
77 | \&\|] | |
78 | .RB "[\|" \-relax "\|]" | |
79 | .RB "[\|" \-r | \-Ur "\|]" | |
80 | .RB "[\|" \-S "\|]" | |
81 | .RB "[\|" \-s "\|]" | |
82 | .RB "[\|" "\-T\ "\c | |
83 | .I commandfile\c | |
84 | \&\|] | |
85 | .RB "[\|" "\-Ttext\ "\c | |
86 | .I textorg\c | |
87 | \&\|] | |
88 | .RB "[\|" "\-Tdata\ "\c | |
89 | .I dataorg\c | |
90 | \&\|] | |
91 | .RB "[\|" "\-Tbss\ "\c | |
92 | .I bssorg\c | |
93 | \&\|] | |
94 | .RB "[\|" \-t "\|]" | |
95 | .RB "[\|" "\-u\ "\c | |
96 | .I sym\c | |
97 | \&] | |
8ddef552 | 98 | .RB "[\|" \-V "\|]" |
0e166a63 RP |
99 | .RB "[\|" \-v "\|]" |
100 | .RB "[\|" \-X "\|]" | |
101 | .RB "[\|" \-x "\|]" | |
0e166a63 RP |
102 | .ad b |
103 | .hy 1 | |
104 | .SH DESCRIPTION | |
105 | \c | |
106 | .B ld\c | |
107 | \& combines a number of object and archive files, relocates | |
108 | their data and ties up symbol references. Often the last step in | |
109 | building a new compiled program to run is a call to \c | |
110 | .B ld\c | |
111 | \&. | |
112 | ||
113 | \c | |
114 | .B ld\c | |
115 | \& accepts Linker Command Language files | |
116 | to provide explicit and total control over the linking process. | |
117 | This man page does not describe the command language; see the `\|\c | |
118 | .B ld\c | |
119 | \|' entry in `\|\c | |
120 | .B info\c | |
121 | \|', or the manual | |
122 | .I | |
123 | ld: the GNU linker | |
124 | \&, for full details on the command language and on other aspects of | |
125 | the GNU linker. | |
126 | ||
127 | This version of \c | |
128 | .B ld\c | |
129 | \& uses the general purpose BFD libraries | |
130 | to operate on object files. This allows \c | |
131 | .B ld\c | |
132 | \& to read, combine, and | |
133 | write object files in many different formats\(em\&for example, COFF or | |
134 | \c | |
135 | .B a.out\c | |
136 | \&. Different formats may be linked together to produce any | |
137 | available kind of object file. You can use `\|\c | |
138 | .B objdump \-i\c | |
139 | \|' to get a list of formats supported on various architectures; see | |
140 | .BR objdump ( 1 ). | |
141 | ||
142 | Aside from its flexibility, the GNU linker is more helpful than other | |
143 | linkers in providing diagnostic information. Many linkers abandon | |
144 | execution immediately upon encountering an error; whenever possible, | |
145 | \c | |
146 | .B ld\c | |
147 | \& continues executing, allowing you to identify other errors | |
148 | (or, in some cases, to get an output file in spite of the error). | |
149 | ||
150 | The GNU linker \c | |
151 | .B ld\c | |
152 | \& is meant to cover a broad range of situations, | |
153 | and to be as compatible as possible with other linkers. As a result, | |
154 | you have many choices to control its behavior through the command line, | |
155 | and through environment variables. | |
156 | ||
157 | .SH OPTIONS | |
158 | The plethora of command-line options may seem intimidating, but in | |
159 | actual practice few of them are used in any particular context. | |
160 | For instance, a frequent use of \c | |
161 | .B ld\c | |
162 | \& is to link standard Unix | |
163 | object files on a standard, supported Unix system. On such a system, to | |
164 | link a file \c | |
165 | .B hello.o\c | |
166 | \&: | |
167 | .sp | |
168 | .br | |
169 | $\ ld\ \-o\ output\ /lib/crt0.o\ hello.o\ \-lc | |
170 | .br | |
171 | .sp | |
172 | This tells \c | |
173 | .B ld\c | |
174 | \& to produce a file called \c | |
175 | .B output\c | |
176 | \& as the | |
177 | result of linking the file \c | |
178 | .B /lib/crt0.o\c | |
179 | \& with \c | |
180 | .B hello.o\c | |
181 | \& and | |
182 | the library \c | |
183 | .B libc.a\c | |
184 | \& which will come from the standard search | |
185 | directories. | |
186 | ||
187 | The command-line options to \c | |
188 | .B ld\c | |
189 | \& may be specified in any order, and | |
190 | may be repeated at will. For the most part, repeating an option with a | |
191 | different argument will either have no further effect, or override prior | |
192 | occurrences (those further to the left on the command line) of an | |
193 | option. | |
194 | ||
195 | The exceptions\(em\&which may meaningfully be used more than once\(em\&are | |
196 | \c | |
197 | .B \-A\c | |
198 | \&, \c | |
199 | .B \-b\c | |
200 | \& (or its synonym \c | |
201 | .B \-format\c | |
202 | \&), \c | |
203 | .B \-defsym\c | |
204 | \&, | |
205 | \c | |
206 | .B \-L\c | |
207 | \&, \c | |
208 | .B \-l\c | |
209 | \&, \c | |
210 | .B \-R\c | |
211 | \&, and \c | |
212 | .B \-u\c | |
213 | \&. | |
214 | ||
215 | The list of object files to be linked together, shown as \c | |
8ddef552 | 216 | .I objfile\c |
0e166a63 RP |
217 | \&, |
218 | may follow, precede, or be mixed in with command-line options; save that | |
219 | an \c | |
8ddef552 | 220 | .I objfile\c |
0e166a63 RP |
221 | \& argument may not be placed between an option flag and |
222 | its argument. | |
223 | ||
224 | Usually the linker is invoked with at least one object file, but other | |
225 | forms of binary input files can also be specified with \c | |
226 | .B \-l\c | |
227 | \&, | |
228 | \c | |
229 | .B \-R\c | |
230 | \&, and the script command language. If \c | |
231 | .I no\c | |
232 | \& binary input | |
233 | files at all are specified, the linker does not produce any output, and | |
234 | issues the message `\|\c | |
235 | .B No input files\c | |
236 | \|'. | |
237 | ||
238 | Option arguments must either follow the option letter without intervening | |
239 | whitespace, or be given as separate arguments immediately following the | |
240 | option that requires them. | |
241 | ||
0e166a63 RP |
242 | .TP |
243 | .BI "-A" "architecture"\c | |
244 | \& | |
245 | In the current release of \c | |
246 | .B ld\c | |
247 | \&, this option is useful only for the | |
248 | Intel 960 family of architectures. In that \c | |
249 | .B ld\c | |
250 | \& configuration, the | |
251 | \c | |
252 | .I architecture\c | |
253 | \& argument is one of the two-letter names identifying | |
254 | members of the 960 family; the option specifies the desired output | |
255 | target, and warns of any incompatible instructions in the input files. | |
256 | It also modifies the linker's search strategy for archive libraries, to | |
257 | support the use of libraries specific to each particular | |
258 | architecture, by including in the search loop names suffixed with the | |
259 | string identifying the architecture. | |
260 | ||
261 | For example, if your \c | |
262 | .B ld\c | |
263 | \& command line included `\|\c | |
264 | .B \-ACA\c | |
265 | \|' as | |
266 | well as `\|\c | |
267 | .B \-ltry\c | |
268 | \|', the linker would look (in its built-in search | |
269 | paths, and in any paths you specify with \c | |
270 | .B \-L\c | |
271 | \&) for a library with | |
272 | the names | |
273 | .sp | |
274 | .br | |
275 | try | |
276 | .br | |
277 | libtry.a | |
278 | .br | |
279 | tryca | |
280 | .br | |
281 | libtryca.a | |
282 | .br | |
283 | .sp | |
284 | ||
285 | The first two possibilities would be considered in any event; the last | |
286 | two are due to the use of `\|\c | |
287 | .B \-ACA\c | |
288 | \|'. | |
289 | ||
290 | Future releases of \c | |
291 | .B ld\c | |
292 | \& may support similar functionality for | |
293 | other architecture families. | |
294 | ||
295 | You can meaningfully use \c | |
296 | .B \-A\c | |
297 | \& more than once on a command line, if | |
298 | an architecture family allows combination of target architectures; each | |
299 | use will add another pair of name variants to search for when \c | |
300 | .B \-l\c | |
301 | \& | |
302 | specifies a library. | |
303 | ||
304 | .TP | |
305 | .BI "-b " "input-format"\c | |
306 | \& | |
307 | Specify the binary format for input object files that follow this option | |
308 | on the command line. You don't usually need to specify this, as | |
309 | \c | |
310 | .B ld\c | |
311 | \& is configured to expect as a default input format the most | |
312 | usual format on each machine. \c | |
313 | .I input-format\c | |
314 | \& is a text string, the | |
315 | name of a particular format supported by the BFD libraries. | |
316 | \c | |
317 | .B \-format \c | |
318 | .I input-format\c | |
319 | \&\c | |
346535cc DM |
320 | \& has the same effect, as does the script command |
321 | .BR TARGET . | |
0e166a63 RP |
322 | |
323 | You may want to use this option if you are linking files with an unusual | |
324 | binary format. You can also use \c | |
325 | .B \-b\c | |
326 | \& to switch formats explicitly (when | |
327 | linking object files of different formats), by including | |
328 | \c | |
329 | .B \-b \c | |
330 | .I input-format\c | |
331 | \&\c | |
332 | \& before each group of object files in a | |
333 | particular format. | |
334 | ||
335 | The default format is taken from the environment variable | |
336 | .B GNUTARGET\c | |
337 | \&. You can also define the input | |
338 | format from a script, using the command \c | |
339 | .B TARGET\c | |
340 | \&. | |
341 | ||
342 | .TP | |
343 | .B \-Bstatic | |
344 | This flag is accepted for command-line compatibility with the SunOS linker, | |
345 | but has no effect on \c | |
346 | .B ld\c | |
347 | \&. | |
348 | ||
349 | .TP | |
350 | .BI "-c " "commandfile"\c | |
351 | \& | |
352 | Directs \c | |
353 | .B ld\c | |
354 | \& to read link commands from the file | |
355 | \c | |
356 | .I commandfile\c | |
357 | \&. These commands will completely override \c | |
358 | .B ld\c | |
359 | \&'s | |
360 | default link format (rather than adding to it); \c | |
361 | .I commandfile\c | |
362 | \& must | |
363 | specify everything necessary to describe the target format. | |
364 | ||
365 | ||
366 | You may also include a script of link commands directly in the command | |
367 | line by bracketing it between `\|\c | |
368 | .B {\c | |
369 | \|' and `\|\c | |
370 | .B }\c | |
371 | \|' characters. | |
372 | ||
373 | .TP | |
374 | .B \-d | |
375 | .TP | |
376 | .B \-dc | |
377 | .TP | |
378 | .B \-dp | |
379 | These three options are equivalent; multiple forms are supported for | |
380 | compatibility with other linkers. Use any of them to make \c | |
381 | .B ld\c | |
382 | \& | |
383 | assign space to common symbols even if a relocatable output file is | |
384 | specified (\c | |
385 | .B \-r\c | |
386 | \&). The script command | |
387 | \c | |
388 | .B FORCE_COMMON_ALLOCATION\c | |
389 | \& has the same effect. | |
390 | ||
391 | .TP | |
392 | .BI "-defsym " "symbol"\c | |
393 | \& = \c | |
394 | .I expression\c | |
395 | \& | |
396 | Create a global symbol in the output file, containing the absolute | |
397 | address given by \c | |
398 | .I expression\c | |
399 | \&. You may use this option as many | |
400 | times as necessary to define multiple symbols in the command line. A | |
401 | limited form of arithmetic is supported for the \c | |
402 | .I expression\c | |
403 | \& in this | |
404 | context: you may give a hexadecimal constant or the name of an existing | |
405 | symbol, or use \c | |
406 | .B +\c | |
407 | \& and \c | |
408 | .B \-\c | |
409 | \& to add or subtract hexadecimal | |
410 | constants or symbols. If you need more elaborate expressions, consider | |
411 | using the linker command language from a script. | |
412 | ||
413 | .TP | |
414 | .BI "-e " "entry"\c | |
415 | \& | |
416 | Use \c | |
417 | .I entry\c | |
418 | \& as the explicit symbol for beginning execution of your | |
419 | program, rather than the default entry point. for a | |
420 | discussion of defaults and other ways of specifying the | |
421 | entry point. | |
422 | ||
423 | .TP | |
424 | .B \-F | |
425 | .TP | |
426 | .BI "-F" "format"\c | |
427 | \& | |
428 | Some older linkers used this option throughout a compilation toolchain | |
429 | for specifying object-file format for both input and output object | |
430 | files. \c | |
431 | .B ld\c | |
432 | \&'s mechanisms (the \c | |
433 | .B \-b\c | |
434 | \& or \c | |
435 | .B \-format\c | |
436 | \& options | |
437 | for input files, the \c | |
438 | .B TARGET\c | |
439 | \& command in linker scripts for output | |
440 | files, the \c | |
441 | .B GNUTARGET\c | |
442 | \& environment variable) are more flexible, but | |
443 | but it accepts (and ignores) the \c | |
444 | .B \-F\c | |
445 | \& option flag for compatibility | |
446 | with scripts written to call the old linker. | |
447 | ||
448 | .TP | |
449 | .BI "-format " "input-format"\c | |
450 | \& | |
451 | Synonym for \c | |
452 | .B \-b\c | |
453 | \& \c | |
454 | .I input-format\c | |
455 | \&. | |
456 | ||
457 | .TP | |
458 | .B \-g | |
459 | Accepted, but ignored; provided for compatibility with other tools. | |
460 | ||
8ddef552 DM |
461 | .TP |
462 | .BI "\-G " "size"\c | |
463 | Set the maximum size of objects to be optimized using the GP register | |
464 | to | |
465 | .I size | |
466 | under MIPS ECOFF. Ignored for other object file formats. | |
467 | ||
0e166a63 RP |
468 | .TP |
469 | .B \-i | |
470 | Perform an incremental link (same as option \c | |
471 | .B \-r\c | |
472 | \&). | |
473 | ||
474 | .TP | |
475 | .BI "-l" "ar"\c | |
476 | \& | |
477 | Add an archive file \c | |
478 | .I ar\c | |
479 | \& to the list of files to link. This | |
480 | option may be used any number of times. \c | |
481 | .B ld\c | |
482 | \& will search its | |
483 | path-list for occurrences of \c | |
484 | .B lib\c | |
485 | .I ar\c | |
486 | \&.a\c | |
487 | \& for every \c | |
488 | .I ar\c | |
489 | \& | |
490 | specified. | |
491 | ||
492 | .TP | |
493 | .BI "-L" "searchdir"\c | |
494 | \& | |
495 | This command adds path \c | |
496 | .I searchdir\c | |
497 | \& to the list of paths that | |
498 | \c | |
499 | .B ld\c | |
500 | \& will search for archive libraries. You may use this option | |
501 | any number of times. | |
502 | ||
503 | The default set of paths searched (without being specified with | |
504 | \c | |
505 | .B \-L\c | |
506 | \&) depends on what emulation mode \c | |
507 | .B ld\c | |
508 | \& is using, and in | |
509 | some cases also on how it was configured. The | |
510 | paths can also be specified in a link script with the \c | |
511 | .B SEARCH_DIR\c | |
512 | \& | |
513 | command. | |
514 | ||
515 | .TP | |
516 | .B \-M | |
0e166a63 RP |
517 | Print (to the standard output file) a link map\(em\&diagnostic information |
518 | about where symbols are mapped by \c | |
519 | .B ld\c | |
520 | \&, and information on global | |
521 | common storage allocation. | |
522 | ||
d18a4527 DM |
523 | .TP |
524 | .BI "\-Map " "mapfile"\c | |
525 | Print to the file | |
526 | .I mapfile | |
527 | a link map\(em\&diagnostic information | |
528 | about where symbols are mapped by \c | |
529 | .B ld\c | |
530 | \&, and information on global | |
531 | common storage allocation. | |
532 | ||
8ddef552 DM |
533 | .TP |
534 | .BI "\-m " "emulation"\c | |
535 | Emulate the | |
536 | .I emulation | |
537 | linker. You can list the available emulations with the | |
538 | .I \-V | |
539 | option. This option overrides the compiled-in default, which is the | |
540 | system for which you configured | |
541 | .BR ld . | |
542 | ||
0e166a63 RP |
543 | .TP |
544 | .B \-N | |
545 | specifies readable and writable \c | |
546 | .B text\c | |
547 | \& and \c | |
548 | .B data\c | |
549 | \& sections. If | |
550 | the output format supports Unix style magic numbers, the output is | |
551 | marked as \c | |
552 | .B OMAGIC\c | |
553 | \&. | |
554 | ||
555 | When you use the `\|\c | |
556 | .B \-N\c | |
557 | \&\|' option, the linker does not page-align the | |
558 | data segment. | |
559 | ||
560 | .TP | |
561 | .B \-n | |
562 | sets the text segment to be read only, and \c | |
563 | .B NMAGIC\c | |
564 | \& is written | |
565 | if possible. | |
566 | ||
567 | .TP | |
568 | .B \-noinhibit-exec | |
569 | Normally, the linker will not produce an output file if it encounters | |
570 | errors during the link process. With this flag, you can specify that | |
571 | you wish the output file retained even after non-fatal errors. | |
572 | ||
573 | .TP | |
574 | .BI "-o " "output"\c | |
575 | \& | |
576 | .I output\c | |
577 | \& | |
578 | \c | |
579 | .I output\c | |
580 | \& is a name for the program produced by \c | |
581 | .B ld\c | |
582 | \&; if this | |
583 | option is not specified, the name `\|\c | |
584 | .B a.out\c | |
585 | \|' is used by default. The | |
586 | script command \c | |
587 | .B OUTPUT\c | |
588 | \& can also specify the output file name. | |
589 | ||
346535cc DM |
590 | .TP |
591 | .BI "-oformat " "output-format"\c | |
592 | \& | |
593 | Specify the binary format for the output object file. | |
594 | You don't usually need to specify this, as | |
595 | \c | |
596 | .B ld\c | |
597 | \& is configured to produce as a default output format the most | |
598 | usual format on each machine. \c | |
599 | .I output-format\c | |
600 | \& is a text string, the | |
601 | name of a particular format supported by the BFD libraries. | |
602 | The script command | |
603 | .B OUTPUT_FORMAT | |
604 | can also specify the output format, but this option overrides it. | |
605 | ||
0e166a63 RP |
606 | .TP |
607 | .BI "-R " "filename"\c | |
608 | \& | |
609 | .I file\c | |
610 | \& | |
611 | Read symbol names and their addresses from \c | |
612 | .I filename\c | |
613 | \&, but do not | |
614 | relocate it or include it in the output. This allows your output file | |
615 | to refer symbolically to absolute locations of memory defined in other | |
616 | programs. | |
617 | ||
618 | .TP | |
619 | .B \-relax | |
620 | An option with machine dependent effects. Currently this option is only | |
621 | supported on the H8/300. | |
622 | ||
623 | On some platforms, use this option to perform global optimizations that | |
624 | become possible when the linker resolves addressing in your program, such | |
625 | as relaxing address modes and synthesizing new instructions in the | |
626 | output object file. | |
627 | ||
628 | On platforms where this is not supported, `\|\c | |
629 | .B \-relax\c | |
630 | \&\|' is accepted, but has no effect. | |
631 | ||
632 | .TP | |
633 | .B \-r | |
634 | Generates relocatable output\(em\&i.e., generate an output file that can in | |
635 | turn serve as input to \c | |
636 | .B ld\c | |
637 | \&. This is often called \c | |
638 | .I partial | |
639 | linking\c | |
640 | \&. As a side effect, in environments that support standard Unix | |
641 | magic numbers, this option also sets the output file's magic number to | |
642 | \c | |
643 | .B OMAGIC\c | |
644 | \&. | |
645 | If this option is not specified, an absolute file is produced. When | |
646 | linking C++ programs, this option \c | |
647 | .I will not\c | |
648 | \& resolve references to | |
649 | constructors; \c | |
650 | .B \-Ur\c | |
651 | \& is an alternative. | |
652 | ||
653 | This option does the same as \c | |
654 | .B \-i\c | |
655 | \&. | |
656 | ||
657 | .TP | |
658 | .B \-S | |
659 | Omits debugger symbol information (but not all symbols) from the output file. | |
660 | ||
661 | .TP | |
662 | .B \-s | |
663 | Omits all symbol information from the output file. | |
664 | ||
0e166a63 RP |
665 | .TP |
666 | .BI "-Tbss " "org"\c | |
667 | .TP | |
668 | .BI "-Tdata " "org"\c | |
669 | .TP | |
670 | .BI "-Ttext " "org"\c | |
671 | Use \c | |
672 | .I org\c | |
673 | \& as the starting address for\(em\&respectively\(em\&the | |
674 | \c | |
675 | .B bss\c | |
676 | \&, \c | |
677 | .B data\c | |
678 | \&, or the \c | |
679 | .B text\c | |
680 | \& segment of the output file. | |
681 | \c | |
682 | .I textorg\c | |
683 | \& must be a hexadecimal integer. | |
684 | ||
685 | .TP | |
686 | .BI "-T " "commandfile"\c | |
687 | \& | |
688 | .TP | |
689 | .BI "-T" "commandfile"\c | |
690 | Equivalent to \c | |
691 | .B \-c \c | |
692 | .I commandfile\c | |
693 | \&\c | |
694 | \&; supported for compatibility with | |
695 | other tools. | |
696 | ||
697 | .TP | |
698 | .B \-t | |
699 | Prints names of input files as \c | |
700 | .B ld\c | |
701 | \& processes them. | |
702 | ||
703 | .TP | |
704 | .BI "-u " "sym" | |
705 | Forces \c | |
706 | .I sym\c | |
707 | \& to be entered in the output file as an undefined symbol. | |
708 | This may, for example, trigger linking of additional modules from | |
709 | standard libraries. \c | |
710 | .B \-u\c | |
711 | \& may be repeated with different option | |
712 | arguments to enter additional undefined symbols. | |
713 | ||
714 | .TP | |
715 | .B \-Ur | |
716 | For anything other than C++ programs, this option is equivalent to | |
717 | \c | |
718 | .B \-r\c | |
719 | \&: it generates relocatable output\(em\&i.e., an output file that can in | |
720 | turn serve as input to \c | |
721 | .B ld\c | |
722 | \&. When linking C++ programs, \c | |
723 | .B \-Ur\c | |
724 | \& | |
725 | \c | |
726 | .I will\c | |
727 | \& resolve references to constructors, unlike \c | |
728 | .B \-r\c | |
729 | \&. | |
730 | ||
8ddef552 DM |
731 | .TP |
732 | .B \-V | |
733 | Display the version number for \c | |
734 | .B ld | |
735 | and list the supported emulations. | |
736 | Print which input files can and can not be opened. | |
737 | ||
0e166a63 RP |
738 | .TP |
739 | .B \-v | |
740 | Display the version number for \c | |
741 | .B ld\c | |
742 | \&. | |
8ddef552 | 743 | Print which input files can and can not be opened. |
0e166a63 RP |
744 | |
745 | .TP | |
746 | .B \-X | |
747 | If \c | |
748 | .B \-s\c | |
749 | \& or \c | |
750 | .B \-S\c | |
751 | \& is also specified, delete only local symbols | |
752 | beginning with `\|\c | |
753 | .B L\c | |
754 | \|'. | |
755 | ||
756 | .TP | |
757 | .B \-x | |
758 | If \c | |
759 | .B \-s\c | |
760 | \& or \c | |
761 | .B \-S\c | |
762 | \& is also specified, delete all local symbols, | |
763 | not just those beginning with `\|\c | |
764 | .B L\c | |
765 | \|'. | |
766 | ||
767 | .PP | |
768 | ||
769 | .SH ENVIRONMENT | |
770 | \c | |
8ddef552 | 771 | You can change the behavior of |
0e166a63 | 772 | .B ld\c |
8ddef552 | 773 | \& with the environment variable \c |
0e166a63 | 774 | .B GNUTARGET\c |
8ddef552 | 775 | \&. |
0e166a63 RP |
776 | |
777 | \c | |
778 | .B GNUTARGET\c | |
779 | \& determines the input-file object format if you don't | |
780 | use \c | |
781 | .B \-b\c | |
782 | \& (or its synonym \c | |
783 | .B \-format\c | |
784 | \&). Its value should be one | |
785 | of the BFD names for an input format. If there is no | |
786 | \c | |
787 | .B GNUTARGET\c | |
788 | \& in the environment, \c | |
789 | .B ld\c | |
790 | \& uses the natural format | |
791 | of the host. If \c | |
792 | .B GNUTARGET\c | |
793 | \& is set to \c | |
794 | .B default\c | |
795 | \& then BFD attempts to discover the | |
796 | input format by examining binary input files; this method often | |
797 | succeeds, but there are potential ambiguities, since there is no method | |
798 | of ensuring that the magic number used to flag object-file formats is | |
799 | unique. However, the configuration procedure for BFD on each system | |
800 | places the conventional format for that system first in the search-list, | |
801 | so ambiguities are resolved in favor of convention. | |
802 | ||
0e166a63 RP |
803 | .PP |
804 | ||
805 | .SH "SEE ALSO" | |
806 | ||
807 | .BR objdump ( 1 ) | |
808 | .br | |
809 | .br | |
810 | .RB "`\|" ld "\|' and `\|" binutils "\|'" | |
811 | entries in | |
812 | .B info\c | |
813 | .br | |
814 | .I | |
815 | ld: the GNU linker\c | |
816 | , Steve Chamberlain and Roland Pesch; | |
817 | .I | |
818 | The GNU Binary Utilities\c | |
819 | , Roland H. Pesch. | |
820 | ||
821 | .SH COPYING | |
822 | Copyright (c) 1991, 1992 Free Software Foundation, Inc. | |
823 | .PP | |
824 | Permission is granted to make and distribute verbatim copies of | |
825 | this manual provided the copyright notice and this permission notice | |
826 | are preserved on all copies. | |
827 | .PP | |
828 | Permission is granted to copy and distribute modified versions of this | |
829 | manual under the conditions for verbatim copying, provided that the | |
830 | entire resulting derived work is distributed under the terms of a | |
831 | permission notice identical to this one. | |
832 | .PP | |
833 | Permission is granted to copy and distribute translations of this | |
834 | manual into another language, under the above conditions for modified | |
835 | versions, except that this permission notice may be included in | |
836 | translations approved by the Free Software Foundation instead of in | |
837 | the original English. |