0,0 → 1,704 |
/* ldcref.c -- output a cross reference table |
Copyright 1996-2013 Free Software Foundation, Inc. |
Written by Ian Lance Taylor <ian@cygnus.com> |
|
This file is part of the GNU Binutils. |
|
This program is free software; you can redistribute it and/or modify |
it under the terms of the GNU General Public License as published by |
the Free Software Foundation; either version 3 of the License, or |
(at your option) any later version. |
|
This program is distributed in the hope that it will be useful, |
but WITHOUT ANY WARRANTY; without even the implied warranty of |
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
GNU General Public License for more details. |
|
You should have received a copy of the GNU General Public License |
along with this program; if not, write to the Free Software |
Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, |
MA 02110-1301, USA. */ |
|
|
/* This file holds routines that manage the cross reference table. |
The table is used to generate cross reference reports. It is also |
used to implement the NOCROSSREFS command in the linker script. */ |
|
#include "sysdep.h" |
#include "bfd.h" |
#include "bfdlink.h" |
#include "libiberty.h" |
#include "demangle.h" |
#include "objalloc.h" |
|
#include "ld.h" |
#include "ldmain.h" |
#include "ldmisc.h" |
#include "ldexp.h" |
#include "ldlang.h" |
|
/* We keep an instance of this structure for each reference to a |
symbol from a given object. */ |
|
struct cref_ref { |
/* The next reference. */ |
struct cref_ref *next; |
/* The object. */ |
bfd *abfd; |
/* True if the symbol is defined. */ |
unsigned int def : 1; |
/* True if the symbol is common. */ |
unsigned int common : 1; |
/* True if the symbol is undefined. */ |
unsigned int undef : 1; |
}; |
|
/* We keep a hash table of symbols. Each entry looks like this. */ |
|
struct cref_hash_entry { |
struct bfd_hash_entry root; |
/* The demangled name. */ |
const char *demangled; |
/* References to and definitions of this symbol. */ |
struct cref_ref *refs; |
}; |
|
/* This is what the hash table looks like. */ |
|
struct cref_hash_table { |
struct bfd_hash_table root; |
}; |
|
/* Forward declarations. */ |
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static void output_one_cref (FILE *, struct cref_hash_entry *); |
static void check_local_sym_xref (lang_input_statement_type *); |
static bfd_boolean check_nocrossref (struct cref_hash_entry *, void *); |
static void check_refs (const char *, bfd_boolean, asection *, bfd *, |
struct lang_nocrossrefs *); |
static void check_reloc_refs (bfd *, asection *, void *); |
|
/* Look up an entry in the cref hash table. */ |
|
#define cref_hash_lookup(table, string, create, copy) \ |
((struct cref_hash_entry *) \ |
bfd_hash_lookup (&(table)->root, (string), (create), (copy))) |
|
/* Traverse the cref hash table. */ |
|
#define cref_hash_traverse(table, func, info) \ |
(bfd_hash_traverse \ |
(&(table)->root, \ |
(bfd_boolean (*) (struct bfd_hash_entry *, void *)) (func), \ |
(info))) |
|
/* The cref hash table. */ |
|
static struct cref_hash_table cref_table; |
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/* Whether the cref hash table has been initialized. */ |
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static bfd_boolean cref_initialized; |
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/* The number of symbols seen so far. */ |
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static size_t cref_symcount; |
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/* Used to take a snapshot of the cref hash table when starting to |
add syms from an as-needed library. */ |
static struct bfd_hash_entry **old_table; |
static unsigned int old_size; |
static unsigned int old_count; |
static void *old_tab; |
static void *alloc_mark; |
static size_t tabsize, entsize, refsize; |
static size_t old_symcount; |
|
/* Create an entry in a cref hash table. */ |
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static struct bfd_hash_entry * |
cref_hash_newfunc (struct bfd_hash_entry *entry, |
struct bfd_hash_table *table, |
const char *string) |
{ |
struct cref_hash_entry *ret = (struct cref_hash_entry *) entry; |
|
/* Allocate the structure if it has not already been allocated by a |
subclass. */ |
if (ret == NULL) |
ret = ((struct cref_hash_entry *) |
bfd_hash_allocate (table, sizeof (struct cref_hash_entry))); |
if (ret == NULL) |
return NULL; |
|
/* Call the allocation method of the superclass. */ |
ret = ((struct cref_hash_entry *) |
bfd_hash_newfunc ((struct bfd_hash_entry *) ret, table, string)); |
if (ret != NULL) |
{ |
/* Set local fields. */ |
ret->demangled = NULL; |
ret->refs = NULL; |
|
/* Keep a count of the number of entries created in the hash |
table. */ |
++cref_symcount; |
} |
|
return &ret->root; |
} |
|
/* Add a symbol to the cref hash table. This is called for every |
global symbol that is seen during the link. */ |
|
void |
add_cref (const char *name, |
bfd *abfd, |
asection *section, |
bfd_vma value ATTRIBUTE_UNUSED) |
{ |
struct cref_hash_entry *h; |
struct cref_ref *r; |
|
if (! cref_initialized) |
{ |
if (!bfd_hash_table_init (&cref_table.root, cref_hash_newfunc, |
sizeof (struct cref_hash_entry))) |
einfo (_("%X%P: bfd_hash_table_init of cref table failed: %E\n")); |
cref_initialized = TRUE; |
} |
|
h = cref_hash_lookup (&cref_table, name, TRUE, FALSE); |
if (h == NULL) |
einfo (_("%X%P: cref_hash_lookup failed: %E\n")); |
|
for (r = h->refs; r != NULL; r = r->next) |
if (r->abfd == abfd) |
break; |
|
if (r == NULL) |
{ |
r = (struct cref_ref *) bfd_hash_allocate (&cref_table.root, sizeof *r); |
if (r == NULL) |
einfo (_("%X%P: cref alloc failed: %E\n")); |
r->next = h->refs; |
h->refs = r; |
r->abfd = abfd; |
r->def = FALSE; |
r->common = FALSE; |
r->undef = FALSE; |
} |
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if (bfd_is_und_section (section)) |
r->undef = TRUE; |
else if (bfd_is_com_section (section)) |
r->common = TRUE; |
else |
r->def = TRUE; |
} |
|
/* Called before loading an as-needed library to take a snapshot of |
the cref hash table, and after we have loaded or found that the |
library was not needed. */ |
|
bfd_boolean |
handle_asneeded_cref (bfd *abfd ATTRIBUTE_UNUSED, |
enum notice_asneeded_action act) |
{ |
unsigned int i; |
|
if (!cref_initialized) |
return TRUE; |
|
if (act == notice_as_needed) |
{ |
char *old_ent, *old_ref; |
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for (i = 0; i < cref_table.root.size; i++) |
{ |
struct bfd_hash_entry *p; |
struct cref_hash_entry *c; |
struct cref_ref *r; |
|
for (p = cref_table.root.table[i]; p != NULL; p = p->next) |
{ |
entsize += cref_table.root.entsize; |
c = (struct cref_hash_entry *) p; |
for (r = c->refs; r != NULL; r = r->next) |
refsize += sizeof (struct cref_ref); |
} |
} |
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tabsize = cref_table.root.size * sizeof (struct bfd_hash_entry *); |
old_tab = xmalloc (tabsize + entsize + refsize); |
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alloc_mark = bfd_hash_allocate (&cref_table.root, 1); |
if (alloc_mark == NULL) |
return FALSE; |
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memcpy (old_tab, cref_table.root.table, tabsize); |
old_ent = (char *) old_tab + tabsize; |
old_ref = (char *) old_ent + entsize; |
old_table = cref_table.root.table; |
old_size = cref_table.root.size; |
old_count = cref_table.root.count; |
old_symcount = cref_symcount; |
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for (i = 0; i < cref_table.root.size; i++) |
{ |
struct bfd_hash_entry *p; |
struct cref_hash_entry *c; |
struct cref_ref *r; |
|
for (p = cref_table.root.table[i]; p != NULL; p = p->next) |
{ |
memcpy (old_ent, p, cref_table.root.entsize); |
old_ent = (char *) old_ent + cref_table.root.entsize; |
c = (struct cref_hash_entry *) p; |
for (r = c->refs; r != NULL; r = r->next) |
{ |
memcpy (old_ref, r, sizeof (struct cref_ref)); |
old_ref = (char *) old_ref + sizeof (struct cref_ref); |
} |
} |
} |
return TRUE; |
} |
|
if (act == notice_not_needed) |
{ |
char *old_ent, *old_ref; |
|
if (old_tab == NULL) |
{ |
/* The only way old_tab can be NULL is if the cref hash table |
had not been initialised when notice_as_needed. */ |
bfd_hash_table_free (&cref_table.root); |
cref_initialized = FALSE; |
return TRUE; |
} |
|
old_ent = (char *) old_tab + tabsize; |
old_ref = (char *) old_ent + entsize; |
cref_table.root.table = old_table; |
cref_table.root.size = old_size; |
cref_table.root.count = old_count; |
memcpy (cref_table.root.table, old_tab, tabsize); |
cref_symcount = old_symcount; |
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for (i = 0; i < cref_table.root.size; i++) |
{ |
struct bfd_hash_entry *p; |
struct cref_hash_entry *c; |
struct cref_ref *r; |
|
for (p = cref_table.root.table[i]; p != NULL; p = p->next) |
{ |
memcpy (p, old_ent, cref_table.root.entsize); |
old_ent = (char *) old_ent + cref_table.root.entsize; |
c = (struct cref_hash_entry *) p; |
for (r = c->refs; r != NULL; r = r->next) |
{ |
memcpy (r, old_ref, sizeof (struct cref_ref)); |
old_ref = (char *) old_ref + sizeof (struct cref_ref); |
} |
} |
} |
|
objalloc_free_block ((struct objalloc *) cref_table.root.memory, |
alloc_mark); |
} |
else if (act != notice_needed) |
return FALSE; |
|
free (old_tab); |
old_tab = NULL; |
return TRUE; |
} |
|
/* Copy the addresses of the hash table entries into an array. This |
is called via cref_hash_traverse. We also fill in the demangled |
name. */ |
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static bfd_boolean |
cref_fill_array (struct cref_hash_entry *h, void *data) |
{ |
struct cref_hash_entry ***pph = (struct cref_hash_entry ***) data; |
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ASSERT (h->demangled == NULL); |
h->demangled = bfd_demangle (link_info.output_bfd, h->root.string, |
DMGL_ANSI | DMGL_PARAMS); |
if (h->demangled == NULL) |
h->demangled = h->root.string; |
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**pph = h; |
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++*pph; |
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return TRUE; |
} |
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/* Sort an array of cref hash table entries by name. */ |
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static int |
cref_sort_array (const void *a1, const void *a2) |
{ |
const struct cref_hash_entry * const *p1 = |
(const struct cref_hash_entry * const *) a1; |
const struct cref_hash_entry * const *p2 = |
(const struct cref_hash_entry * const *) a2; |
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return strcmp ((*p1)->demangled, (*p2)->demangled); |
} |
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/* Write out the cref table. */ |
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#define FILECOL (50) |
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void |
output_cref (FILE *fp) |
{ |
int len; |
struct cref_hash_entry **csyms, **csym_fill, **csym, **csym_end; |
const char *msg; |
|
fprintf (fp, _("\nCross Reference Table\n\n")); |
msg = _("Symbol"); |
fprintf (fp, "%s", msg); |
len = strlen (msg); |
while (len < FILECOL) |
{ |
putc (' ', fp); |
++len; |
} |
fprintf (fp, _("File\n")); |
|
if (! cref_initialized) |
{ |
fprintf (fp, _("No symbols\n")); |
return; |
} |
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csyms = (struct cref_hash_entry **) xmalloc (cref_symcount * sizeof (*csyms)); |
|
csym_fill = csyms; |
cref_hash_traverse (&cref_table, cref_fill_array, &csym_fill); |
ASSERT ((size_t) (csym_fill - csyms) == cref_symcount); |
|
qsort (csyms, cref_symcount, sizeof (*csyms), cref_sort_array); |
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csym_end = csyms + cref_symcount; |
for (csym = csyms; csym < csym_end; csym++) |
output_one_cref (fp, *csym); |
} |
|
/* Output one entry in the cross reference table. */ |
|
static void |
output_one_cref (FILE *fp, struct cref_hash_entry *h) |
{ |
int len; |
struct bfd_link_hash_entry *hl; |
struct cref_ref *r; |
|
hl = bfd_link_hash_lookup (link_info.hash, h->root.string, FALSE, |
FALSE, TRUE); |
if (hl == NULL) |
einfo ("%P: symbol `%T' missing from main hash table\n", |
h->root.string); |
else |
{ |
/* If this symbol is defined in a dynamic object but never |
referenced by a normal object, then don't print it. */ |
if (hl->type == bfd_link_hash_defined) |
{ |
if (hl->u.def.section->output_section == NULL) |
return; |
if (hl->u.def.section->owner != NULL |
&& (hl->u.def.section->owner->flags & DYNAMIC) != 0) |
{ |
for (r = h->refs; r != NULL; r = r->next) |
if ((r->abfd->flags & DYNAMIC) == 0) |
break; |
if (r == NULL) |
return; |
} |
} |
} |
|
fprintf (fp, "%s ", h->demangled); |
len = strlen (h->demangled) + 1; |
|
for (r = h->refs; r != NULL; r = r->next) |
{ |
if (r->def) |
{ |
while (len < FILECOL) |
{ |
putc (' ', fp); |
++len; |
} |
lfinfo (fp, "%B\n", r->abfd); |
len = 0; |
} |
} |
|
for (r = h->refs; r != NULL; r = r->next) |
{ |
if (r->common) |
{ |
while (len < FILECOL) |
{ |
putc (' ', fp); |
++len; |
} |
lfinfo (fp, "%B\n", r->abfd); |
len = 0; |
} |
} |
|
for (r = h->refs; r != NULL; r = r->next) |
{ |
if (! r->def && ! r->common) |
{ |
while (len < FILECOL) |
{ |
putc (' ', fp); |
++len; |
} |
lfinfo (fp, "%B\n", r->abfd); |
len = 0; |
} |
} |
|
ASSERT (len == 0); |
} |
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/* Check for prohibited cross references. */ |
|
void |
check_nocrossrefs (void) |
{ |
if (! cref_initialized) |
return; |
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cref_hash_traverse (&cref_table, check_nocrossref, NULL); |
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lang_for_each_file (check_local_sym_xref); |
} |
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/* Check for prohibited cross references to local and section symbols. */ |
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static void |
check_local_sym_xref (lang_input_statement_type *statement) |
{ |
bfd *abfd; |
asymbol **syms; |
|
abfd = statement->the_bfd; |
if (abfd == NULL) |
return; |
|
if (!bfd_generic_link_read_symbols (abfd)) |
einfo (_("%B%F: could not read symbols: %E\n"), abfd); |
|
for (syms = bfd_get_outsymbols (abfd); *syms; ++syms) |
{ |
asymbol *sym = *syms; |
if (sym->flags & (BSF_GLOBAL | BSF_WARNING | BSF_INDIRECT | BSF_FILE)) |
continue; |
if ((sym->flags & (BSF_LOCAL | BSF_SECTION_SYM)) != 0 |
&& sym->section->output_section != NULL) |
{ |
const char *outsecname, *symname; |
struct lang_nocrossrefs *ncrs; |
struct lang_nocrossref *ncr; |
|
outsecname = sym->section->output_section->name; |
symname = NULL; |
if ((sym->flags & BSF_SECTION_SYM) == 0) |
symname = sym->name; |
for (ncrs = nocrossref_list; ncrs != NULL; ncrs = ncrs->next) |
for (ncr = ncrs->list; ncr != NULL; ncr = ncr->next) |
if (strcmp (ncr->name, outsecname) == 0) |
check_refs (symname, FALSE, sym->section, abfd, ncrs); |
} |
} |
} |
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/* Check one symbol to see if it is a prohibited cross reference. */ |
|
static bfd_boolean |
check_nocrossref (struct cref_hash_entry *h, void *ignore ATTRIBUTE_UNUSED) |
{ |
struct bfd_link_hash_entry *hl; |
asection *defsec; |
const char *defsecname; |
struct lang_nocrossrefs *ncrs; |
struct lang_nocrossref *ncr; |
struct cref_ref *ref; |
|
hl = bfd_link_hash_lookup (link_info.hash, h->root.string, FALSE, |
FALSE, TRUE); |
if (hl == NULL) |
{ |
einfo (_("%P: symbol `%T' missing from main hash table\n"), |
h->root.string); |
return TRUE; |
} |
|
if (hl->type != bfd_link_hash_defined |
&& hl->type != bfd_link_hash_defweak) |
return TRUE; |
|
defsec = hl->u.def.section->output_section; |
if (defsec == NULL) |
return TRUE; |
defsecname = bfd_get_section_name (defsec->owner, defsec); |
|
for (ncrs = nocrossref_list; ncrs != NULL; ncrs = ncrs->next) |
for (ncr = ncrs->list; ncr != NULL; ncr = ncr->next) |
if (strcmp (ncr->name, defsecname) == 0) |
for (ref = h->refs; ref != NULL; ref = ref->next) |
check_refs (hl->root.string, TRUE, hl->u.def.section, |
ref->abfd, ncrs); |
|
return TRUE; |
} |
|
/* The struct is used to pass information from check_refs to |
check_reloc_refs through bfd_map_over_sections. */ |
|
struct check_refs_info { |
const char *sym_name; |
asection *defsec; |
struct lang_nocrossrefs *ncrs; |
asymbol **asymbols; |
bfd_boolean global; |
}; |
|
/* This function is called for each symbol defined in a section which |
prohibits cross references. We need to look through all references |
to this symbol, and ensure that the references are not from |
prohibited sections. */ |
|
static void |
check_refs (const char *name, |
bfd_boolean global, |
asection *sec, |
bfd *abfd, |
struct lang_nocrossrefs *ncrs) |
{ |
struct check_refs_info info; |
|
/* We need to look through the relocations for this BFD, to see |
if any of the relocations which refer to this symbol are from |
a prohibited section. Note that we need to do this even for |
the BFD in which the symbol is defined, since even a single |
BFD might contain a prohibited cross reference. */ |
|
if (!bfd_generic_link_read_symbols (abfd)) |
einfo (_("%B%F: could not read symbols: %E\n"), abfd); |
|
info.sym_name = name; |
info.global = global; |
info.defsec = sec; |
info.ncrs = ncrs; |
info.asymbols = bfd_get_outsymbols (abfd); |
bfd_map_over_sections (abfd, check_reloc_refs, &info); |
} |
|
/* This is called via bfd_map_over_sections. INFO->SYM_NAME is a symbol |
defined in INFO->DEFSECNAME. If this section maps into any of the |
sections listed in INFO->NCRS, other than INFO->DEFSECNAME, then we |
look through the relocations. If any of the relocations are to |
INFO->SYM_NAME, then we report a prohibited cross reference error. */ |
|
static void |
check_reloc_refs (bfd *abfd, asection *sec, void *iarg) |
{ |
struct check_refs_info *info = (struct check_refs_info *) iarg; |
asection *outsec; |
const char *outsecname; |
asection *outdefsec; |
const char *outdefsecname; |
struct lang_nocrossref *ncr; |
const char *symname; |
bfd_boolean global; |
long relsize; |
arelent **relpp; |
long relcount; |
arelent **p, **pend; |
|
outsec = sec->output_section; |
outsecname = bfd_get_section_name (outsec->owner, outsec); |
|
outdefsec = info->defsec->output_section; |
outdefsecname = bfd_get_section_name (outdefsec->owner, outdefsec); |
|
/* The section where the symbol is defined is permitted. */ |
if (strcmp (outsecname, outdefsecname) == 0) |
return; |
|
for (ncr = info->ncrs->list; ncr != NULL; ncr = ncr->next) |
if (strcmp (outsecname, ncr->name) == 0) |
break; |
|
if (ncr == NULL) |
return; |
|
/* This section is one for which cross references are prohibited. |
Look through the relocations, and see if any of them are to |
INFO->SYM_NAME. If INFO->SYMNAME is NULL, check for relocations |
against the section symbol. If INFO->GLOBAL is TRUE, the |
definition is global, check for relocations against the global |
symbols. Otherwise check for relocations against the local and |
section symbols. */ |
|
symname = info->sym_name; |
global = info->global; |
|
relsize = bfd_get_reloc_upper_bound (abfd, sec); |
if (relsize < 0) |
einfo (_("%B%F: could not read relocs: %E\n"), abfd); |
if (relsize == 0) |
return; |
|
relpp = (arelent **) xmalloc (relsize); |
relcount = bfd_canonicalize_reloc (abfd, sec, relpp, info->asymbols); |
if (relcount < 0) |
einfo (_("%B%F: could not read relocs: %E\n"), abfd); |
|
p = relpp; |
pend = p + relcount; |
for (; p < pend && *p != NULL; p++) |
{ |
arelent *q = *p; |
|
if (q->sym_ptr_ptr != NULL |
&& *q->sym_ptr_ptr != NULL |
&& ((global |
&& (bfd_is_und_section (bfd_get_section (*q->sym_ptr_ptr)) |
|| bfd_is_com_section (bfd_get_section (*q->sym_ptr_ptr)) |
|| ((*q->sym_ptr_ptr)->flags & (BSF_GLOBAL |
| BSF_WEAK)) != 0)) |
|| (!global |
&& ((*q->sym_ptr_ptr)->flags & (BSF_LOCAL |
| BSF_SECTION_SYM)) != 0 |
&& bfd_get_section (*q->sym_ptr_ptr) == info->defsec)) |
&& (symname != NULL |
? strcmp (bfd_asymbol_name (*q->sym_ptr_ptr), symname) == 0 |
: ((*q->sym_ptr_ptr)->flags & BSF_SECTION_SYM) != 0)) |
{ |
/* We found a reloc for the symbol. The symbol is defined |
in OUTSECNAME. This reloc is from a section which is |
mapped into a section from which references to OUTSECNAME |
are prohibited. We must report an error. */ |
einfo (_("%X%C: prohibited cross reference from %s to `%T' in %s\n"), |
abfd, sec, q->address, outsecname, |
bfd_asymbol_name (*q->sym_ptr_ptr), outdefsecname); |
} |
} |
|
free (relpp); |
} |