* README:: The README File
* Emulations:: How linker emulations are generated
* Emulation Walkthrough:: A Walkthrough of a Typical Emulation
+* Architecture Specific:: Some Architecture Specific Notes
* GNU Free Documentation License:: GNU Free Documentation License
@end menu
@end itemize
+@node Architecture Specific
+@chapter Some Architecture Specific Notes
+
+This is the place for notes on the behavior of @code{ld} on
+specific platforms. Currently, only Intel x86 is documented (and
+of that, only the auto-import behavior for DLLs).
+
+@menu
+* ix86:: Intel x86
+@end menu
+
+@node ix86
+@section Intel x86
+
+@table @emph
+@code{ld} can create DLLs that operate with various runtimes available
+on a common x86 operating system. These runtimes include native (using
+the mingw "platform"), cygwin, and pw.
+
+@item auto-import from DLLs
+@enumerate
+@item
+With this feature on, DLL clients can import variables from DLL
+without any concern from their side (for example, without any source
+code modifications). Auto-import can be enabled using the
+@code{--enable-auto-import} flag, or disabled via the
+@code{--disable-auto-import} flag. Auto-import is disabled by default.
+
+@item
+This is done completely in bounds of the PE specification (to be fair,
+there's a minor violation of the spec at one point, but in practice
+auto-import works on all known variants of that common x86 operating
+system) So, the resulting DLL can be used with any other PE
+compiler/linker.
+
+@item
+Auto-import is fully compatible with standard import method, in which
+variables are decorated using attribute modifiers. Libraries of either
+type may be mixed together.
+
+@item
+Overhead (space): 8 bytes per imported symbol, plus 20 for each
+reference to it; Overhead (load time): negligible; Overhead
+(virtual/physical memory): should be less than effect of DLL
+relocation.
+@end enumerate
+
+Motivation
+
+The obvious and only way to get rid of dllimport insanity is
+to make client access variable directly in the DLL, bypassing
+the extra dereference imposed by ordinary DLL runtime linking.
+I.e., whenever client contains someting like
+
+@code{mov dll_var,%eax,}
+
+address of dll_var in the command should be relocated to point
+into loaded DLL. The aim is to make OS loader do so, and than
+make ld help with that. Import section of PE made following
+way: there's a vector of structures each describing imports
+from particular DLL. Each such structure points to two other
+parellel vectors: one holding imported names, and one which
+will hold address of corresponding imported name. So, the
+solution is de-vectorize these structures, making import
+locations be sparse and pointing directly into code.
+
+Implementation
+
+For each reference of data symbol to be imported from DLL (to
+set of which belong symbols with name <sym>, if __imp_<sym> is
+found in implib), the import fixup entry is generated. That
+entry is of type IMAGE_IMPORT_DESCRIPTOR and stored in .idata$3
+subsection. Each fixup entry contains pointer to symbol's address
+within .text section (marked with __fuN_<sym> symbol, where N is
+integer), pointer to DLL name (so, DLL name is referenced by
+multiple entries), and pointer to symbol name thunk. Symbol name
+thunk is singleton vector (__nm_th_<symbol>) pointing to
+IMAGE_IMPORT_BY_NAME structure (__nm_<symbol>) directly containing
+imported name. Here comes that "om the edge" problem mentioned above:
+PE specification rambles that name vector (OriginalFirstThunk) should
+run in parallel with addresses vector (FirstThunk), i.e. that they
+should have same number of elements and terminated with zero. We violate
+this, since FirstThunk points directly into machine code. But in
+practice, OS loader implemented the sane way: it goes thru
+OriginalFirstThunk and puts addresses to FirstThunk, not something
+else. It once again should be noted that dll and symbol name
+structures are reused across fixup entries and should be there
+anyway to support standard import stuff, so sustained overhead is
+20 bytes per reference. Other question is whether having several
+IMAGE_IMPORT_DESCRIPTORS for the same DLL is possible. Answer is yes,
+it is done even by native compiler/linker (libth32's functions are in
+fact resident in windows9x kernel32.dll, so if you use it, you have
+two IMAGE_IMPORT_DESCRIPTORS for kernel32.dll). Yet other question is
+whether referencing the same PE structures several times is valid.
+The answer is why not, prohibiting that (detecting violation) would
+require more work on behalf of loader than not doing it.
+
+@end table
+
@node GNU Free Documentation License
@chapter GNU Free Documentation License
************************************************************************/
+/************************************************************************
+
+ Auto-import feature by Paul Sokolovsky
+
+ Quick facts:
+
+ 1. With this feature on, DLL clients can import variables from DLL
+ without any concern from their side (for example, without any source
+ code modifications).
+
+ 2. This is done completely in bounds of the PE specification (to be fair,
+ there's a place where it pokes nose out of, but in practise it works).
+ So, resulting module can be used with any other PE compiler/linker.
+
+ 3. Auto-import is fully compatible with standard import method and they
+ can be mixed together.
+
+ 4. Overheads: space: 8 bytes per imported symbol, plus 20 for each
+ reference to it; load time: negligible; virtual/physical memory: should be
+ less than effect of DLL relocation, and I sincerely hope it doesn't affect
+ DLL sharability (too much).
+
+ Idea
+
+ The obvious and only way to get rid of dllimport insanity is to make client
+ access variable directly in the DLL, bypassing extra dereference. I.e.,
+ whenever client contains someting like
+
+ mov dll_var,%eax,
+
+ address of dll_var in the command should be relocated to point into loaded
+ DLL. The aim is to make OS loader do so, and than make ld help with that.
+ Import section of PE made following way: there's a vector of structures
+ each describing imports from particular DLL. Each such structure points
+ to two other parellel vectors: one holding imported names, and one which
+ will hold address of corresponding imported name. So, the solution is
+ de-vectorize these structures, making import locations be sparse and
+ pointing directly into code. Before continuing, it is worth a note that,
+ while authors strives to make PE act ELF-like, there're some other people
+ make ELF act PE-like: elfvector, ;-) .
+
+ Implementation
+
+ For each reference of data symbol to be imported from DLL (to set of which
+ belong symbols with name <sym>, if __imp_<sym> is found in implib), the
+ import fixup entry is generated. That entry is of type
+ IMAGE_IMPORT_DESCRIPTOR and stored in .idata$3 subsection. Each
+ fixup entry contains pointer to symbol's address within .text section
+ (marked with __fuN_<sym> symbol, where N is integer), pointer to DLL name
+ (so, DLL name is referenced by multiple entries), and pointer to symbol
+ name thunk. Symbol name thunk is singleton vector (__nm_th_<symbol>)
+ pointing to IMAGE_IMPORT_BY_NAME structure (__nm_<symbol>) directly
+ containing imported name. Here comes that "om the edge" problem mentioned
+ above: PE specification rambles that name vector (OriginalFirstThunk)
+ should run in parallel with addresses vector (FirstThunk), i.e. that they
+ should have same number of elements and terminated with zero. We violate
+ this, since FirstThunk points directly into machine code. But in practise,
+ OS loader implemented the sane way: it goes thru OriginalFirstThunk and
+ puts addresses to FirstThunk, not something else. It once again should be
+ noted that dll and symbol name structures are reused across fixup entries
+ and should be there anyway to support standard import stuff, so sustained
+ overhead is 20 bytes per reference. Other question is whether having several
+ IMAGE_IMPORT_DESCRIPTORS for the same DLL is possible. Answer is yes, it is
+ done even by native compiler/linker (libth32's functions are in fact reside
+ in windows9x kernel32.dll, so if you use it, you have two
+ IMAGE_IMPORT_DESCRIPTORS for kernel32.dll). Yet other question is whether
+ referencing the same PE structures several times is valid. The answer is why
+ not, prohibitting that (detecting violation) would require more work on
+ behalf of loader than not doing it.
+
+
+ See also: ld/emultempl/pe.em
+
+ ************************************************************************/
+
+static void
+add_bfd_to_link (bfd *abfd, CONST char *name,
+ struct bfd_link_info *link_info);
+
/* for emultempl/pe.em */
def_file *pe_def_file = 0;
int pe_dll_stdcall_aliases = 0;
int pe_dll_warn_dup_exports = 0;
int pe_dll_compat_implib = 0;
+int pe_dll_extra_pe_debug = 0;
/************************************************************************
int underscored;
} pe_details_type;
+typedef struct {
+ char *name;
+ int len;
+} autofilter_entry_type;
+
#define PE_ARCH_i386 1
#define PE_ARCH_sh 2
#define PE_ARCH_mips 3
static pe_details_type *pe_details;
+static autofilter_entry_type autofilter_symbollist[] = {
+ { "DllMain@12", 10 },
+ { "DllEntryPoint@0", 15 },
+ { "DllMainCRTStartup@12", 20 },
+ { "_cygwin_dll_entry@12", 20 },
+ { "_cygwin_crt0_common@8", 21 },
+ { "_cygwin_noncygwin_dll_entry@12", 30 },
+ { "impure_ptr", 10 },
+ { NULL, 0 }
+};
+/* Do not specify library suffix explicitly, to allow for dllized versions */
+static autofilter_entry_type autofilter_liblist[] = {
+ { "libgcc.", 7 },
+ { "libstdc++.", 10 },
+ { "libmingw32.", 11 },
+ { NULL, 0 }
+};
+static autofilter_entry_type autofilter_objlist[] = {
+ { "crt0.o", 6 },
+ { "crt1.o", 6 },
+ { "crt2.o", 6 },
+ { NULL, 0 }
+};
+static autofilter_entry_type autofilter_symbolprefixlist[] = {
+/* { "__imp_", 6 }, */
+/* Do __imp_ explicitly to save time */
+ { "__rtti_", 7 },
+ { "__builtin_", 10 },
+ { "_head_", 6 }, /* don't export symbols specifying internal DLL layout */
+ { "_fmode", 6 },
+ { "_impure_ptr", 11 },
+ { "cygwin_attach_dll", 17 },
+ { "cygwin_premain0", 15 },
+ { "cygwin_premain1", 15 },
+ { "cygwin_premain2", 15 },
+ { "cygwin_premain3", 15 },
+ { "environ", 7 },
+ { NULL, 0 }
+};
+static autofilter_entry_type autofilter_symbolsuffixlist[] = {
+ { "_iname", 6 },
+ { NULL, 0 }
+};
+
#define U(str) (pe_details->underscored ? "_" str : str)
void
free (local_copy);
}
+/*
+ abfd is a bfd containing n (or NULL)
+ It can be used for contextual checks.
+*/
static int
-auto_export (d, n)
+auto_export (abfd, d, n)
+ bfd *abfd;
def_file *d;
const char *n;
{
int i;
struct exclude_list_struct *ex;
+ autofilter_entry_type *afptr;
+
+ /* we should not re-export imported stuff */
+ if (strncmp (n, "_imp__", 6) == 0)
+ return 0;
+
for (i = 0; i < d->num_exports; i++)
if (strcmp (d->exports[i].name, n) == 0)
return 0;
if (pe_dll_do_default_excludes)
{
- if (strcmp (n, "DllMain@12") == 0)
- return 0;
- if (strcmp (n, "DllEntryPoint@0") == 0)
- return 0;
- if (strcmp (n, "impure_ptr") == 0)
- return 0;
+ if (pe_dll_extra_pe_debug)
+ {
+ printf ("considering exporting: %s, abfd=%p, abfd->my_arc=%p\n",
+ n, abfd, abfd->my_archive);
+ }
+
+ /* First of all, make context checks:
+ Don't export anything from libgcc */
+ if (abfd && abfd->my_archive)
+ {
+ afptr = autofilter_liblist;
+ while (afptr->name)
+ {
+ if (strstr (abfd->my_archive->filename, afptr->name))
+ return 0;
+ afptr++;
+ }
+ }
+
+ /* Next, exclude symbols from certain startup objects */
+ {
+ char *p;
+ afptr = autofilter_objlist;
+ while (afptr->name)
+ {
+ if (abfd &&
+ (p = strstr (abfd->filename, afptr->name)) &&
+ (*(p + afptr->len - 1) == 0))
+ return 0;
+ afptr++;
+ }
+ }
+
+ /* Don't try to blindly exclude all symbols
+ that begin with '__'; this was tried and
+ it is too restrictive */
+
+ /* Then, exclude specific symbols */
+ afptr = autofilter_symbollist;
+ while (afptr->name)
+ {
+ if (strcmp (n, afptr->name) == 0)
+ return 0;
+ afptr++;
+ }
+
+ /* Next, exclude symbols starting with ... */
+ afptr = autofilter_symbolprefixlist;
+ while (afptr->name)
+ {
+ if (strncmp (n, afptr->name, afptr->len) == 0)
+ return 0;
+ afptr++;
+ }
+
+ /* Finally, exclude symbols ending with ... */
+ {
+ int len = strlen(n);
+ afptr = autofilter_symbolsuffixlist;
+ while (afptr->name)
+ {
+ if ((len >= afptr->len) &&
+ /* add 1 to insure match with trailing '\0' */
+ strncmp (n + len - afptr->len, afptr->name,
+ afptr->len + 1) == 0)
+ return 0;
+ afptr++;
+ }
+ }
}
for (ex = excludes; ex; ex = ex->next)
if (strcmp (n, ex->string) == 0)
for (j = 0; j < nsyms; j++)
{
/* We should export symbols which are either global or not
- anything at all. (.bss data is the latter) */
- if ((symbols[j]->flags & BSF_GLOBAL)
- || (symbols[j]->flags == BSF_NO_FLAGS))
+ anything at all. (.bss data is the latter)
+ We should not export undefined symbols
+ */
+ if (symbols[j]->section != &bfd_und_section
+ && ((symbols[j]->flags & BSF_GLOBAL)
+ || (symbols[j]->flags == BFD_FORT_COMM_DEFAULT_VALUE)))
{
const char *sn = symbols[j]->name;
+
+ /* we should not re-export imported stuff */
+ {
+ char *name = (char *) xmalloc (strlen (sn) + 2 + 6);
+ sprintf (name, "%s%s", U("_imp_"), sn);
+ blhe = bfd_link_hash_lookup (info->hash, name,
+ false, false, false);
+ free (name);
+
+ if (blhe && blhe->type == bfd_link_hash_defined)
+ continue;
+ }
+
if (*sn == '_')
sn++;
- if (auto_export (pe_def_file, sn))
- {
- def_file_export *p;
- p=def_file_add_export (pe_def_file, sn, 0, -1);
- /* Fill data flag properly, from dlltool.c */
- p->flag_data = !(symbols[j]->flags & BSF_FUNCTION);
- }
+ if (auto_export (b, pe_def_file, sn))
+ {
+ def_file_export *p;
+ p=def_file_add_export (pe_def_file, sn, 0, -1);
+ /* Fill data flag properly, from dlltool.c */
+ p->flag_data = !(symbols[j]->flags & BSF_FUNCTION);
+ }
}
}
}
{
char *tmp = xstrdup (pe_def_file->exports[i].name);
*(strchr (tmp, '@')) = 0;
- if (auto_export (pe_def_file, tmp))
+ if (auto_export (NULL, pe_def_file, tmp))
def_file_add_export (pe_def_file, tmp,
- pe_def_file->exports[i].internal_name, -1);
+ pe_def_file->exports[i].internal_name,
+ -1);
else
free (tmp);
}
}
}
+
+static struct sec *current_sec;
+
+void
+pe_walk_relocs_of_symbol (info, name, cb)
+ struct bfd_link_info *info;
+ CONST char *name;
+ int (*cb) (arelent *);
+{
+ bfd *b;
+ struct sec *s;
+
+ for (b = info->input_bfds; b; b = b->link_next)
+ {
+ arelent **relocs;
+ int relsize, nrelocs, i;
+
+ for (s = b->sections; s; s = s->next)
+ {
+ asymbol **symbols;
+ int nsyms, symsize;
+ int flags = bfd_get_section_flags (b, s);
+
+ /* Skip discarded linkonce sections */
+ if (flags & SEC_LINK_ONCE
+ && s->output_section == bfd_abs_section_ptr)
+ continue;
+
+ current_sec=s;
+
+ symsize = bfd_get_symtab_upper_bound (b);
+ symbols = (asymbol **) xmalloc (symsize);
+ nsyms = bfd_canonicalize_symtab (b, symbols);
+
+ relsize = bfd_get_reloc_upper_bound (b, s);
+ relocs = (arelent **) xmalloc ((size_t) relsize);
+ nrelocs = bfd_canonicalize_reloc (b, s, relocs, symbols);
+
+ for (i = 0; i < nrelocs; i++)
+ {
+ struct symbol_cache_entry *sym = *relocs[i]->sym_ptr_ptr;
+ if (!strcmp(name,sym->name)) cb(relocs[i]);
+ }
+ free (relocs);
+ /* Warning: the allocated symbols are remembered in BFD and reused
+ later, so don't free them! */
+ /* free (symbols); */
+ }
+ }
+}
+
/************************************************************************
Gather all the relocations and build the .reloc section
for (s = b->sections; s; s = s->next)
total_relocs += s->reloc_count;
- reloc_data = (reloc_data_type *) xmalloc (total_relocs * sizeof (reloc_data_type));
+ reloc_data =
+ (reloc_data_type *) xmalloc (total_relocs * sizeof (reloc_data_type));
total_relocs = 0;
bi = 0;
for (i = 0; i < nrelocs; i++)
{
+ if (pe_dll_extra_pe_debug)
+ {
+ struct symbol_cache_entry *sym = *relocs[i]->sym_ptr_ptr;
+ printf("rel: %s\n",sym->name);
+ }
if (!relocs[i]->howto->pc_relative
&& relocs[i]->howto->type != pe_details->imagebase_reloc)
{
if (pe_def_file->num_exports > 0)
{
- fprintf (out, "\nEXPORTS\n\n");
+ fprintf (out, "EXPORTS\n");
for (i = 0; i < pe_def_file->num_exports; i++)
{
def_file_export *e = pe_def_file->exports + i;
bfd_set_arch_mach (abfd, pe_details->bfd_arch, 0);
symptr = 0;
- symtab = (asymbol **) xmalloc (10 * sizeof (asymbol *));
+ symtab = (asymbol **) xmalloc (11 * sizeof (asymbol *));
tx = quick_section (abfd, ".text", SEC_CODE|SEC_HAS_CONTENTS, 2);
id7 = quick_section (abfd, ".idata$7", SEC_HAS_CONTENTS, 2);
id5 = quick_section (abfd, ".idata$5", SEC_HAS_CONTENTS, 2);
quick_symbol (abfd, U (""), exp->internal_name, "", tx, BSF_GLOBAL, 0);
quick_symbol (abfd, U ("_head_"), dll_symname, "", UNDSEC, BSF_GLOBAL, 0);
quick_symbol (abfd, U ("_imp__"), exp->internal_name, "", id5, BSF_GLOBAL, 0);
+ /* symbol to reference ord/name of imported symbol, used to implement
+ auto-import */
+ quick_symbol (abfd, U("_nm__"), exp->internal_name, "", id6, BSF_GLOBAL, 0);
if (pe_dll_compat_implib)
quick_symbol (abfd, U ("__imp_"), exp->internal_name, "",
id5, BSF_GLOBAL, 0);
return abfd;
}
+static bfd *
+make_singleton_name_thunk (import, parent)
+ char *import;
+ bfd *parent;
+{
+ /* name thunks go to idata$4 */
+
+ asection *id4;
+ unsigned char *d4;
+ char *oname;
+ bfd *abfd;
+
+ oname = (char *) xmalloc (20);
+ sprintf (oname, "nmth%06d.o", tmp_seq);
+ tmp_seq++;
+
+ abfd = bfd_create (oname, parent);
+ bfd_find_target (pe_details->object_target, abfd);
+ bfd_make_writable (abfd);
+
+ bfd_set_format (abfd, bfd_object);
+ bfd_set_arch_mach (abfd, pe_details->bfd_arch, 0);
+
+ symptr = 0;
+ symtab = (asymbol **) xmalloc (3 * sizeof (asymbol *));
+ id4 = quick_section (abfd, ".idata$4", SEC_HAS_CONTENTS, 2);
+ quick_symbol (abfd, U ("_nm_thnk_"), import, "", id4, BSF_GLOBAL, 0);
+ quick_symbol (abfd, U ("_nm_"), import, "", UNDSEC, BSF_GLOBAL, 0);
+
+ bfd_set_section_size (abfd, id4, 8);
+ d4 = (unsigned char *) xmalloc (4);
+ id4->contents = d4;
+ memset (d4, 0, 8);
+ quick_reloc (abfd, 0, BFD_RELOC_RVA, 2);
+ save_relocs (id4);
+
+ bfd_set_symtab (abfd, symtab, symptr);
+
+ bfd_set_section_contents (abfd, id4, d4, 0, 8);
+
+ bfd_make_readable (abfd);
+ return abfd;
+}
+
+static char *
+make_import_fixup_mark (rel)
+ arelent *rel;
+{
+ /* we convert reloc to symbol, for later reference */
+ static int counter;
+ static char *fixup_name = NULL;
+ static int buffer_len = 0;
+
+ struct symbol_cache_entry *sym = *rel->sym_ptr_ptr;
+
+ bfd *abfd = bfd_asymbol_bfd (sym);
+ struct coff_link_hash_entry *myh = NULL;
+
+ if (!fixup_name)
+ {
+ fixup_name = (char *) xmalloc (384);
+ buffer_len = 384;
+ }
+
+ if (strlen (sym->name) + 25 > buffer_len)
+ /* assume 25 chars for "__fu" + counter + "_". If counter is
+ bigger than 20 digits long, we've got worse problems than
+ overflowing this buffer... */
+ {
+ free (fixup_name);
+ /* new buffer size is length of symbol, plus 25, but then
+ rounded up to the nearest multiple of 128 */
+ buffer_len = ((strlen (sym->name) + 25) + 127) & ~127;
+ fixup_name = (char *) xmalloc (buffer_len);
+ }
+
+ sprintf (fixup_name, "__fu%d_%s", counter++, sym->name);
+
+ bfd_coff_link_add_one_symbol (&link_info, abfd, fixup_name, BSF_GLOBAL,
+ current_sec, /* sym->section, */
+ rel->address, NULL, true, false,
+ (struct bfd_link_hash_entry **) &myh);
+
+/*
+ printf("type:%d\n",myh->type);
+ printf("%s\n",myh->root.u.def.section->name);
+*/
+ return fixup_name;
+}
+
+
+/*
+ * .section .idata$3
+ * .rva __nm_thnk_SYM (singleton thunk with name of func)
+ * .long 0
+ * .long 0
+ * .rva __my_dll_iname (name of dll)
+ * .rva __fuNN_SYM (pointer to reference (address) in text)
+ *
+ */
+
+static bfd *
+make_import_fixup_entry (name, fixup_name, dll_symname,parent)
+ char *name;
+ char *fixup_name;
+ char *dll_symname;
+ bfd *parent;
+{
+ asection *id3;
+ unsigned char *d3;
+ char *oname;
+ bfd *abfd;
+
+ oname = (char *) xmalloc (20);
+ sprintf (oname, "fu%06d.o", tmp_seq);
+ tmp_seq++;
+
+ abfd = bfd_create (oname, parent);
+ bfd_find_target (pe_details->object_target, abfd);
+ bfd_make_writable (abfd);
+
+ bfd_set_format (abfd, bfd_object);
+ bfd_set_arch_mach (abfd, pe_details->bfd_arch, 0);
+
+ symptr = 0;
+ symtab = (asymbol **) xmalloc (6 * sizeof (asymbol *));
+ id3 = quick_section (abfd, ".idata$3", SEC_HAS_CONTENTS, 2);
+/*
+ quick_symbol (abfd, U("_head_"), dll_symname, "", id2, BSF_GLOBAL, 0);
+*/
+ quick_symbol (abfd, U ("_nm_thnk_"), name, "", UNDSEC, BSF_GLOBAL, 0);
+ quick_symbol (abfd, U (""), dll_symname, "_iname", UNDSEC, BSF_GLOBAL, 0);
+ quick_symbol (abfd, "", fixup_name, "", UNDSEC, BSF_GLOBAL, 0);
+
+ bfd_set_section_size (abfd, id3, 20);
+ d3 = (unsigned char *) xmalloc (20);
+ id3->contents = d3;
+ memset (d3, 0, 20);
+
+ quick_reloc (abfd, 0, BFD_RELOC_RVA, 1);
+ quick_reloc (abfd, 12, BFD_RELOC_RVA, 2);
+ quick_reloc (abfd, 16, BFD_RELOC_RVA, 3);
+ save_relocs (id3);
+
+ bfd_set_symtab (abfd, symtab, symptr);
+
+ bfd_set_section_contents (abfd, id3, d3, 0, 20);
+
+ bfd_make_readable (abfd);
+ return abfd;
+}
+
+void
+pe_create_import_fixup (rel)
+ arelent *rel;
+{
+ char buf[300];
+ struct symbol_cache_entry *sym = *rel->sym_ptr_ptr;
+ struct bfd_link_hash_entry *name_thunk_sym;
+ CONST char *name = sym->name;
+ char *fixup_name = make_import_fixup_mark (rel);
+
+ sprintf (buf, U ("_nm_thnk_%s"), name);
+
+ name_thunk_sym = bfd_link_hash_lookup (link_info.hash, buf, 0, 0, 1);
+
+ if (!name_thunk_sym || name_thunk_sym->type != bfd_link_hash_defined)
+ {
+ bfd *b = make_singleton_name_thunk (name, output_bfd);
+ add_bfd_to_link (b, b->filename, &link_info);
+
+ /* If we ever use autoimport, we have to cast text section writable */
+ config.text_read_only = false;
+ }
+
+ {
+ extern char *pe_data_import_dll;
+ bfd *b = make_import_fixup_entry (name, fixup_name, pe_data_import_dll,
+ output_bfd);
+ add_bfd_to_link (b, b->filename, &link_info);
+ }
+}
+
+
void
pe_dll_generate_implib (def, impfilename)
def_file *def;
static void
add_bfd_to_link (abfd, name, link_info)
bfd *abfd;
- char *name;
+ CONST char *name;
struct bfd_link_info *link_info;
{
lang_input_statement_type *fake_file;