Bug Summary

File:src/gnu/usr.bin/binutils-2.17/binutils/rddbg.c
Warning:line 172, column 8
Value stored to 'other' is never read

Annotated Source Code

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clang -cc1 -cc1 -triple amd64-unknown-openbsd7.0 -analyze -disable-free -disable-llvm-verifier -discard-value-names -main-file-name rddbg.c -analyzer-store=region -analyzer-opt-analyze-nested-blocks -analyzer-checker=core -analyzer-checker=apiModeling -analyzer-checker=unix -analyzer-checker=deadcode -analyzer-checker=security.insecureAPI.UncheckedReturn -analyzer-checker=security.insecureAPI.getpw -analyzer-checker=security.insecureAPI.gets -analyzer-checker=security.insecureAPI.mktemp -analyzer-checker=security.insecureAPI.mkstemp -analyzer-checker=security.insecureAPI.vfork -analyzer-checker=nullability.NullPassedToNonnull -analyzer-checker=nullability.NullReturnedFromNonnull -analyzer-output plist -w -setup-static-analyzer -mrelocation-model pic -pic-level 1 -pic-is-pie -mframe-pointer=all -relaxed-aliasing -fno-rounding-math -mconstructor-aliases -munwind-tables -target-cpu x86-64 -target-feature +retpoline-indirect-calls -target-feature +retpoline-indirect-branches -tune-cpu generic -debugger-tuning=gdb -fcoverage-compilation-dir=/usr/src/gnu/usr.bin/binutils-2.17/obj/binutils -resource-dir /usr/local/lib/clang/13.0.0 -D HAVE_CONFIG_H -I . -I /usr/src/gnu/usr.bin/binutils-2.17/binutils -I . -D _GNU_SOURCE -I . -I /usr/src/gnu/usr.bin/binutils-2.17/binutils -I ../bfd -I /usr/src/gnu/usr.bin/binutils-2.17/binutils/../bfd -I /usr/src/gnu/usr.bin/binutils-2.17/binutils/../include -I /usr/src/gnu/usr.bin/binutils-2.17/binutils/../intl -I ../intl -D LOCALEDIR="/usr/share/locale" -D bin_dummy_emulation=bin_vanilla_emulation -D PIE_DEFAULT=1 -internal-isystem /usr/local/lib/clang/13.0.0/include -internal-externc-isystem /usr/include -O2 -fdebug-compilation-dir=/usr/src/gnu/usr.bin/binutils-2.17/obj/binutils -ferror-limit 19 -fwrapv -D_RET_PROTECTOR -ret-protector -fgnuc-version=4.2.1 -vectorize-loops -vectorize-slp -fno-builtin-malloc -fno-builtin-calloc -fno-builtin-realloc -fno-builtin-valloc -fno-builtin-free -fno-builtin-strdup -fno-builtin-strndup -analyzer-output=html -faddrsig -D__GCC_HAVE_DWARF2_CFI_ASM=1 -o /home/ben/Projects/vmm/scan-build/2022-01-12-194120-40624-1 -x c /usr/src/gnu/usr.bin/binutils-2.17/binutils/rddbg.c
1/* rddbg.c -- Read debugging information into a generic form.
2 Copyright 1995, 1996, 1997, 2000, 2002, 2003, 2005
3 Free Software Foundation, Inc.
4 Written by Ian Lance Taylor <ian@cygnus.com>.
5
6 This file is part of GNU Binutils.
7
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 2 of the License, or
11 (at your option) any later version.
12
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
17
18 You should have received a copy of the GNU General Public License
19 along with this program; if not, write to the Free Software
20 Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA
21 02110-1301, USA. */
22
23/* This file reads debugging information into a generic form. This
24 file knows how to dig the debugging information out of an object
25 file. */
26
27#include "bfd.h"
28#include "bucomm.h"
29#include "libiberty.h"
30#include "debug.h"
31#include "budbg.h"
32
33static bfd_boolean read_section_stabs_debugging_info
34 (bfd *, asymbol **, long, void *, bfd_boolean *);
35static bfd_boolean read_symbol_stabs_debugging_info
36 (bfd *, asymbol **, long, void *, bfd_boolean *);
37static bfd_boolean read_ieee_debugging_info (bfd *, void *, bfd_boolean *);
38static void save_stab (int, int, bfd_vma, const char *);
39static void stab_context (void);
40static void free_saved_stabs (void);
41
42/* Read debugging information from a BFD. Returns a generic debugging
43 pointer. */
44
45void *
46read_debugging_info (bfd *abfd, asymbol **syms, long symcount)
47{
48 void *dhandle;
49 bfd_boolean found;
50
51 dhandle = debug_init ();
52 if (dhandle == NULL((void*)0))
53 return NULL((void*)0);
54
55 if (! read_section_stabs_debugging_info (abfd, syms, symcount, dhandle,
56 &found))
57 return NULL((void*)0);
58
59 if (bfd_get_flavour (abfd)((abfd)->xvec->flavour) == bfd_target_aout_flavour)
60 {
61 if (! read_symbol_stabs_debugging_info (abfd, syms, symcount, dhandle,
62 &found))
63 return NULL((void*)0);
64 }
65
66 if (bfd_get_flavour (abfd)((abfd)->xvec->flavour) == bfd_target_ieee_flavour)
67 {
68 if (! read_ieee_debugging_info (abfd, dhandle, &found))
69 return NULL((void*)0);
70 }
71
72 /* Try reading the COFF symbols if we didn't find any stabs in COFF
73 sections. */
74 if (! found
75 && bfd_get_flavour (abfd)((abfd)->xvec->flavour) == bfd_target_coff_flavour
76 && symcount > 0)
77 {
78 if (! parse_coff (abfd, syms, symcount, dhandle))
79 return NULL((void*)0);
80 found = TRUE1;
81 }
82
83 if (! found)
84 {
85 non_fatal (_("%s: no recognized debugging information")("%s: no recognized debugging information"),
86 bfd_get_filename (abfd)((char *) (abfd)->filename));
87 return NULL((void*)0);
88 }
89
90 return dhandle;
91}
92
93/* Read stabs in sections debugging information from a BFD. */
94
95static bfd_boolean
96read_section_stabs_debugging_info (bfd *abfd, asymbol **syms, long symcount,
97 void *dhandle, bfd_boolean *pfound)
98{
99 static struct
100 {
101 const char *secname;
102 const char *strsecname;
103 }
104 names[] =
105 {
106 { ".stab", ".stabstr" },
107 { "LC_SYMTAB.stabs", "LC_SYMTAB.stabstr" },
108 { "$GDB_SYMBOLS$", "$GDB_STRINGS$" }
109 };
110 unsigned int i;
111 void *shandle;
112
113 *pfound = FALSE0;
114 shandle = NULL((void*)0);
115
116 for (i = 0; i < sizeof names / sizeof names[0]; i++)
117 {
118 asection *sec, *strsec;
119
120 sec = bfd_get_section_by_name (abfd, names[i].secname);
121 strsec = bfd_get_section_by_name (abfd, names[i].strsecname);
122 if (sec != NULL((void*)0) && strsec != NULL((void*)0))
123 {
124 bfd_size_type stabsize, strsize;
125 bfd_byte *stabs, *strings;
126 bfd_byte *stab;
127 bfd_size_type stroff, next_stroff;
128
129 stabsize = bfd_section_size (abfd, sec)((sec)->size);
130 stabs = (bfd_byte *) xmalloc (stabsize);
131 if (! bfd_get_section_contents (abfd, sec, stabs, 0, stabsize))
132 {
133 fprintf (stderr(&__sF[2]), "%s: %s: %s\n",
134 bfd_get_filename (abfd)((char *) (abfd)->filename), names[i].secname,
135 bfd_errmsg (bfd_get_error ()));
136 return FALSE0;
137 }
138
139 strsize = bfd_section_size (abfd, strsec)((strsec)->size);
140 strings = (bfd_byte *) xmalloc (strsize);
141 if (! bfd_get_section_contents (abfd, strsec, strings, 0, strsize))
142 {
143 fprintf (stderr(&__sF[2]), "%s: %s: %s\n",
144 bfd_get_filename (abfd)((char *) (abfd)->filename), names[i].strsecname,
145 bfd_errmsg (bfd_get_error ()));
146 return FALSE0;
147 }
148
149 if (shandle == NULL((void*)0))
150 {
151 shandle = start_stab (dhandle, abfd, TRUE1, syms, symcount);
152 if (shandle == NULL((void*)0))
153 return FALSE0;
154 }
155
156 *pfound = TRUE1;
157
158 stroff = 0;
159 next_stroff = 0;
160 for (stab = stabs; stab < stabs + stabsize; stab += 12)
161 {
162 unsigned int strx;
163 int type;
164 int other;
165 int desc;
166 bfd_vma value;
167
168 /* This code presumes 32 bit values. */
169
170 strx = bfd_get_32 (abfd, stab)((*((abfd)->xvec->bfd_getx32)) (stab));
171 type = bfd_get_8 (abfd, stab + 4)(*(unsigned char *) (stab + 4) & 0xff);
172 other = bfd_get_8 (abfd, stab + 5)(*(unsigned char *) (stab + 5) & 0xff);
Value stored to 'other' is never read
173 desc = bfd_get_16 (abfd, stab + 6)((*((abfd)->xvec->bfd_getx16)) (stab + 6));
174 value = bfd_get_32 (abfd, stab + 8)((*((abfd)->xvec->bfd_getx32)) (stab + 8));
175
176 if (type == 0)
177 {
178 /* Special type 0 stabs indicate the offset to the
179 next string table. */
180 stroff = next_stroff;
181 next_stroff += value;
182 }
183 else
184 {
185 char *f, *s;
186
187 f = NULL((void*)0);
188
189 if (stroff + strx > strsize)
190 {
191 fprintf (stderr(&__sF[2]), "%s: %s: stab entry %ld is corrupt, strx = 0x%x, type = %d\n",
192 bfd_get_filename (abfd)((char *) (abfd)->filename), names[i].secname,
193 (long) (stab - stabs) / 12, strx, type);
194 continue;
195 }
196
197 s = (char *) strings + stroff + strx;
198
199 while (*s != '\0' && s[strlen (s) - 1] == '\\'
200 && stab + 12 < stabs + stabsize)
201 {
202 char *p;
203
204 stab += 12;
205 p = s + strlen (s) - 1;
206 *p = '\0';
207 s = concat (s,
208 ((char *) strings
209 + stroff
210 + bfd_get_32 (abfd, stab)((*((abfd)->xvec->bfd_getx32)) (stab))),
211 (const char *) NULL((void*)0));
212
213 /* We have to restore the backslash, because, if
214 the linker is hashing stabs strings, we may
215 see the same string more than once. */
216 *p = '\\';
217
218 if (f != NULL((void*)0))
219 free (f);
220 f = s;
221 }
222
223 save_stab (type, desc, value, s);
224
225 if (! parse_stab (dhandle, shandle, type, desc, value, s))
226 {
227 stab_context ();
228 free_saved_stabs ();
229 return FALSE0;
230 }
231
232 /* Don't free f, since I think the stabs code
233 expects strings to hang around. This should be
234 straightened out. FIXME. */
235 }
236 }
237
238 free_saved_stabs ();
239 free (stabs);
240
241 /* Don't free strings, since I think the stabs code expects
242 the strings to hang around. This should be straightened
243 out. FIXME. */
244 }
245 }
246
247 if (shandle != NULL((void*)0))
248 {
249 if (! finish_stab (dhandle, shandle))
250 return FALSE0;
251 }
252
253 return TRUE1;
254}
255
256/* Read stabs in the symbol table. */
257
258static bfd_boolean
259read_symbol_stabs_debugging_info (bfd *abfd, asymbol **syms, long symcount,
260 void *dhandle, bfd_boolean *pfound)
261{
262 void *shandle;
263 asymbol **ps, **symend;
264
265 shandle = NULL((void*)0);
266 symend = syms + symcount;
267 for (ps = syms; ps < symend; ps++)
268 {
269 symbol_info i;
270
271 bfd_get_symbol_info (abfd, *ps, &i)((*((abfd)->xvec->_bfd_get_symbol_info)) (abfd,*ps,&
i));
272
273 if (i.type == '-')
274 {
275 const char *s;
276 char *f;
277
278 if (shandle == NULL((void*)0))
279 {
280 shandle = start_stab (dhandle, abfd, FALSE0, syms, symcount);
281 if (shandle == NULL((void*)0))
282 return FALSE0;
283 }
284
285 *pfound = TRUE1;
286
287 s = i.name;
288 f = NULL((void*)0);
289 while (s[strlen (s) - 1] == '\\'
290 && ps + 1 < symend)
291 {
292 char *sc, *n;
293
294 ++ps;
295 sc = xstrdup (s);
296 sc[strlen (sc) - 1] = '\0';
297 n = concat (sc, bfd_asymbol_name (*ps)((*ps)->name), (const char *) NULL((void*)0));
298 free (sc);
299 if (f != NULL((void*)0))
300 free (f);
301 f = n;
302 s = n;
303 }
304
305 save_stab (i.stab_type, i.stab_desc, i.value, s);
306
307 if (! parse_stab (dhandle, shandle, i.stab_type, i.stab_desc,
308 i.value, s))
309 {
310 stab_context ();
311 free_saved_stabs ();
312 return FALSE0;
313 }
314
315 /* Don't free f, since I think the stabs code expects
316 strings to hang around. This should be straightened out.
317 FIXME. */
318 }
319 }
320
321 free_saved_stabs ();
322
323 if (shandle != NULL((void*)0))
324 {
325 if (! finish_stab (dhandle, shandle))
326 return FALSE0;
327 }
328
329 return TRUE1;
330}
331
332/* Read IEEE debugging information. */
333
334static bfd_boolean
335read_ieee_debugging_info (bfd *abfd, void *dhandle, bfd_boolean *pfound)
336{
337 asection *dsec;
338 bfd_size_type size;
339 bfd_byte *contents;
340
341 /* The BFD backend puts the debugging information into a section
342 named .debug. */
343
344 dsec = bfd_get_section_by_name (abfd, ".debug");
345 if (dsec == NULL((void*)0))
346 return TRUE1;
347
348 size = bfd_section_size (abfd, dsec)((dsec)->size);
349 contents = (bfd_byte *) xmalloc (size);
350 if (! bfd_get_section_contents (abfd, dsec, contents, 0, size))
351 return FALSE0;
352
353 if (! parse_ieee (dhandle, abfd, contents, size))
354 return FALSE0;
355
356 free (contents);
357
358 *pfound = TRUE1;
359
360 return TRUE1;
361}
362
363/* Record stabs strings, so that we can give some context for errors. */
364
365#define SAVE_STABS_COUNT(16) (16)
366
367struct saved_stab
368{
369 int type;
370 int desc;
371 bfd_vma value;
372 char *string;
373};
374
375static struct saved_stab saved_stabs[SAVE_STABS_COUNT(16)];
376static int saved_stabs_index;
377
378/* Save a stabs string. */
379
380static void
381save_stab (int type, int desc, bfd_vma value, const char *string)
382{
383 if (saved_stabs[saved_stabs_index].string != NULL((void*)0))
384 free (saved_stabs[saved_stabs_index].string);
385 saved_stabs[saved_stabs_index].type = type;
386 saved_stabs[saved_stabs_index].desc = desc;
387 saved_stabs[saved_stabs_index].value = value;
388 saved_stabs[saved_stabs_index].string = xstrdup (string);
389 saved_stabs_index = (saved_stabs_index + 1) % SAVE_STABS_COUNT(16);
390}
391
392/* Provide context for an error. */
393
394static void
395stab_context (void)
396{
397 int i;
398
399 fprintf (stderr(&__sF[2]), _("Last stabs entries before error:\n")("Last stabs entries before error:\n"));
400 fprintf (stderr(&__sF[2]), "n_type n_desc n_value string\n");
401
402 i = saved_stabs_index;
403 do
404 {
405 struct saved_stab *stabp;
406
407 stabp = saved_stabs + i;
408 if (stabp->string != NULL((void*)0))
409 {
410 const char *s;
411
412 s = bfd_get_stab_name (stabp->type);
413 if (s != NULL((void*)0))
414 fprintf (stderr(&__sF[2]), "%-6s", s);
415 else if (stabp->type == 0)
416 fprintf (stderr(&__sF[2]), "HdrSym");
417 else
418 fprintf (stderr(&__sF[2]), "%-6d", stabp->type);
419 fprintf (stderr(&__sF[2]), " %-6d ", stabp->desc);
420 fprintf_vma (stderr, stabp->value)fprintf ((&__sF[2]), "%016lx", stabp->value);
421 if (stabp->type != 0)
422 fprintf (stderr(&__sF[2]), " %s", stabp->string);
423 fprintf (stderr(&__sF[2]), "\n");
424 }
425 i = (i + 1) % SAVE_STABS_COUNT(16);
426 }
427 while (i != saved_stabs_index);
428}
429
430/* Free the saved stab strings. */
431
432static void
433free_saved_stabs (void)
434{
435 int i;
436
437 for (i = 0; i < SAVE_STABS_COUNT(16); i++)
438 {
439 if (saved_stabs[i].string != NULL((void*)0))
440 {
441 free (saved_stabs[i].string);
442 saved_stabs[i].string = NULL((void*)0);
443 }
444 }
445
446 saved_stabs_index = 0;
447}