* ldlang.h (struct lang_nocrossref): Define.
(struct lang_nocrossrefs): Define.
(nocrossref_list): Declare.
(lang_add_nocrossref): Declare.
* ldlex.l: Recognize NOCROSSREFS keyword.
* ldgram.y (%union): Add nocrossref field.
(NOCROSSREFS): New terminal.
(ifile_p1): Recognize NOCROSSREFS.
(nocrossref_list): New nonterminal.
* ldlang.c (nocrossref_list): Define.
(lang_add_nocrossref): New function.
* ldmain.c (main): If nocrossref_list is not NULL, call
check_nocrossrefs.
(warning_callback): Free symbols if there is no place to store
them.
(notice): Call add_cref if nocrossref_list is not NULL.
* ldcref.c: Include "ldexp.h" and "ldlang.h".
(check_nocrossrefs): New function.
(check_nocrossref): New static function.
(struct check_refs_info): Define.
(check_refs, check_reloc_refs): New static functions.
* Makefile.in: Rebuild dependencies.
* ld.texinfo (Option Commands): Document NOCROSSREFS.
Thu Aug 1 12:52:19 1996 Ian Lance Taylor <ian@cygnus.com>
+ * ld.h (check_nocrossrefs): Declare.
+ * ldlang.h (struct lang_nocrossref): Define.
+ (struct lang_nocrossrefs): Define.
+ (nocrossref_list): Declare.
+ (lang_add_nocrossref): Declare.
+ * ldlex.l: Recognize NOCROSSREFS keyword.
+ * ldgram.y (%union): Add nocrossref field.
+ (NOCROSSREFS): New terminal.
+ (ifile_p1): Recognize NOCROSSREFS.
+ (nocrossref_list): New nonterminal.
+ * ldlang.c (nocrossref_list): Define.
+ (lang_add_nocrossref): New function.
+ * ldmain.c (main): If nocrossref_list is not NULL, call
+ check_nocrossrefs.
+ (warning_callback): Free symbols if there is no place to store
+ them.
+ (notice): Call add_cref if nocrossref_list is not NULL.
+ * ldcref.c: Include "ldexp.h" and "ldlang.h".
+ (check_nocrossrefs): New function.
+ (check_nocrossref): New static function.
+ (struct check_refs_info): Define.
+ (check_refs, check_reloc_refs): New static functions.
+ * Makefile.in: Rebuild dependencies.
+ * ld.texinfo (Option Commands): Document NOCROSSREFS.
+
+ * ld.texinfo (Section Placement): Improve the wording of the
+ wildcard documentation. Mention that wildcards are only searched
+ for on the command line, not in the file system.
+
* emultempl/sunos.em (gld${EMULATION_NAME}_after_open): Move
definition of lib_path inside condition where it is used.
* Linker scripts may now contain shell wildcard characters for file and section
names.
+* The NOCROSSREFS command was added to the linker script language.
+
Changes since version 2.6:
* New option --cref to print out a cross reference table.
output file format. If that variable is also absent, @code{ld} uses
the default format configured for your machine in the BFD libraries.
@end ifclear
+
+@cindex cross references
+@kindex NOCROSSREFS ( @var{sections} )
+@item NOCROSSREFS ( @var{section} @var{section} @dots{} )
+This command may be used to tell @code{ld} to issue an error about any
+references among certain sections.
+
+In certain types of programs, particularly on embedded systems, when one
+section is loaded into memory, another section will not be. Any direct
+references between the two sections would be errors. For example, it
+would be an error if code in one section called a function defined in
+the other section.
+
+The @code{NOCROSSREFS} command takes a list of section names. If
+@code{ld} detects any cross references between the sections, it reports
+an error and returns a non-zero exit status. The @code{NOCROSSREFS}
+command uses output section names, defined in the @code{SECTIONS}
+command. It does not use the names of input sections.
@end table
@ifset GENERIC
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
-/* This file holds routines that manage the cross reference table. */
+/* 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 "bfd.h"
#include "sysdep.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. */
static boolean cref_fill_array PARAMS ((struct cref_hash_entry *, PTR));
static int cref_sort_array PARAMS ((const PTR, const PTR));
static void output_one_cref PARAMS ((FILE *, struct cref_hash_entry *));
+static boolean check_nocrossref PARAMS ((struct cref_hash_entry *, PTR));
+static void check_refs
+ PARAMS ((struct cref_hash_entry *, struct bfd_link_hash_entry *,
+ struct lang_nocrossrefs *));
+static void check_reloc_refs PARAMS ((bfd *, asection *, PTR));
/* Look up an entry in the cref hash table. */
ASSERT (len == 0);
}
+
+/* Check for prohibited cross references. */
+
+void
+check_nocrossrefs ()
+{
+ if (! cref_initialized)
+ return;
+
+ cref_hash_traverse (&cref_table, check_nocrossref, (PTR) NULL);
+}
+
+/* Check one symbol to see if it is a prohibited cross reference. */
+
+/*ARGSUSED*/
+static boolean
+check_nocrossref (h, ignore)
+ struct cref_hash_entry *h;
+ PTR ignore;
+{
+ struct bfd_link_hash_entry *hl;
+ asection *defsec;
+ const char *defsecname;
+ struct lang_nocrossrefs *ncrs;
+ struct lang_nocrossref *ncr;
+
+ 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;
+ 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)
+ check_refs (h, hl, 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
+{
+ struct cref_hash_entry *h;
+ asection *defsec;
+ struct lang_nocrossrefs *ncrs;
+ asymbol **asymbols;
+ boolean same;
+};
+
+/* 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 (h, hl, ncrs)
+ struct cref_hash_entry *h;
+ struct bfd_link_hash_entry *hl;
+ struct lang_nocrossrefs *ncrs;
+{
+ struct cref_ref *ref;
+
+ for (ref = h->refs; ref != NULL; ref = ref->next)
+ {
+ lang_input_statement_type *li;
+ asymbol **asymbols;
+ 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; for this
+ case, we set the SAME field in INFO, which will cause
+ CHECK_RELOCS_REFS to check for relocations against the
+ section as well as against the symbol. */
+
+ li = (lang_input_statement_type *) ref->abfd->usrdata;
+ if (li != NULL && li->asymbols != NULL)
+ asymbols = li->asymbols;
+ else
+ {
+ long symsize;
+ long symbol_count;
+
+ symsize = bfd_get_symtab_upper_bound (ref->abfd);
+ if (symsize < 0)
+ einfo ("%B%F: could not read symbols; %E\n", ref->abfd);
+ asymbols = (asymbol **) xmalloc (symsize);
+ symbol_count = bfd_canonicalize_symtab (ref->abfd, asymbols);
+ if (symbol_count < 0)
+ einfo ("%B%F: could not read symbols: %E\n", ref->abfd);
+ if (li != NULL)
+ {
+ li->asymbols = asymbols;
+ li->symbol_count = symbol_count;
+ }
+ }
+
+ info.h = h;
+ info.defsec = hl->u.def.section;
+ info.ncrs = ncrs;
+ info.asymbols = asymbols;
+ if (ref->abfd == hl->u.def.section->owner)
+ info.same = true;
+ else
+ info.same = false;
+ bfd_map_over_sections (ref->abfd, check_reloc_refs, (PTR) &info);
+
+ if (li == NULL)
+ free (asymbols);
+ }
+}
+
+/* This is called via bfd_map_over_sections. INFO->H 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->H, then we report a prohibited cross reference error. */
+
+static void
+check_reloc_refs (abfd, sec, iarg)
+ bfd *abfd;
+ asection *sec;
+ PTR 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;
+ 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->H. */
+
+ symname = info->h->root.string;
+
+ 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
+ && (strcmp (bfd_asymbol_name (*q->sym_ptr_ptr), symname) == 0
+ || (info->same
+ && *q->sym_ptr_ptr == info->defsec->symbol)))
+ {
+ /* 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);
+}
union etree_union *at;
union etree_union *flags;
} phdr;
+ struct lang_nocrossref *nocrossref;
}
%type <etree> exp opt_exp_with_type mustbe_exp opt_at phdr_type phdr_val
%type <name> memspec_opt casesymlist
%token <integer> INT
%token <name> NAME LNAME
-%type <integer> length
+%type <integer> length
%type <phdr> phdr_qualifiers
+%type <nocrossref> nocrossref_list
%right <token> PLUSEQ MINUSEQ MULTEQ DIVEQ '=' LSHIFTEQ RSHIFTEQ ANDEQ OREQ
%right <token> '?' ':'
%token NOLOAD DSECT COPY INFO OVERLAY
%token NAME LNAME DEFINED TARGET_K SEARCH_DIR MAP ENTRY
%token <integer> SIZEOF NEXT ADDR
-%token STARTUP HLL SYSLIB FLOAT NOFLOAT
+%token STARTUP HLL SYSLIB FLOAT NOFLOAT NOCROSSREFS
%token ORIGIN FILL
%token LENGTH CREATE_OBJECT_SYMBOLS INPUT GROUP OUTPUT CONSTRUCTORS
%token ALIGNMOD AT PROVIDE
{ lang_add_map($3); }
| INCLUDE filename
{ ldfile_open_command_file($2); } ifile_list END
+ | NOCROSSREFS '(' nocrossref_list ')'
+ {
+ lang_add_nocrossref ($3);
+ }
;
input_list:
{ lang_float(false); }
;
+nocrossref_list:
+ /* empty */
+ {
+ $$ = NULL;
+ }
+ | NAME nocrossref_list
+ {
+ struct lang_nocrossref *n;
+
+ n = (struct lang_nocrossref *) xmalloc (sizeof *n);
+ n->name = $1;
+ n->next = $2;
+ $$ = n;
+ }
+ | NAME ',' nocrossref_list
+ {
+ struct lang_nocrossref *n;
+
+ n = (struct lang_nocrossref *) xmalloc (sizeof *n);
+ n->name = $1;
+ n->next = $3;
+ $$ = n;
+ }
+ ;
mustbe_exp: { ldlex_expression(); }
exp
boolean had_output_filename = false;
boolean lang_float_flag = false;
boolean delete_output_file_on_failure = false;
+struct lang_nocrossrefs *nocrossref_list;
etree_type *base; /* Relocation base - or null */
u->output_section_statement.name, pl->name);
}
}
+
+/* Record a list of sections which may not be cross referenced. */
+
+void
+lang_add_nocrossref (l)
+ struct lang_nocrossref *l;
+{
+ struct lang_nocrossrefs *n;
+
+ n = (struct lang_nocrossrefs *) xmalloc (sizeof *n);
+ n->next = nocrossref_list;
+ n->list = l;
+ nocrossref_list = n;
+
+ /* Set notice_all so that we get informed about all symbols. */
+ link_info.notice_all = true;
+}
/* ldlang.h - linker command language support
- Copyright 1991, 1992, 1993, 1994, 1995 Free Software Foundation, Inc.
+ Copyright 1991, 92, 93, 94, 95, 1996 Free Software Foundation, Inc.
This file is part of GLD, the Gnu Linker.
const char *name;
} lang_output_statement_type;
+/* Section types specified in a linker script. */
+
+enum section_type
+{
+ normal_section,
+ dsect_section,
+ copy_section,
+ noload_section,
+ info_section,
+ overlay_section
+};
/* This structure holds a list of program headers describing segments
in which this section should be placed. */
asection *bfd_section;
int flags; /* Or together of all input sections */
- int loadable; /* set from NOLOAD flag in script */
+ enum section_type sectype;
struct memory_region_struct *region;
size_t block_value;
fill_type fill;
/* unsigned int globals_in_this_file;*/
const char *target;
boolean real;
- asection *common_section;
- asection *common_output_section;
- boolean complained;
} lang_input_statement_type;
typedef struct
etree_type *flags;
};
+/* This structure is used to hold a list of sections which may not
+ cross reference each other. */
+
+struct lang_nocrossref
+{
+ struct lang_nocrossref *next;
+ const char *name;
+};
+
+/* The list of nocrossref lists. */
+
+struct lang_nocrossrefs
+{
+ struct lang_nocrossrefs *next;
+ struct lang_nocrossref *list;
+};
+
+extern struct lang_nocrossrefs *nocrossref_list;
+
extern lang_output_section_statement_type *abs_output_section;
extern boolean lang_has_input_file;
extern etree_type *base;
extern void lang_enter_output_section_statement
PARAMS ((const char *output_section_statement_name,
etree_type * address_exp,
- int flags,
+ enum section_type sectype,
bfd_vma block_value,
etree_type *align,
etree_type *subalign,
PARAMS ((const char *, etree_type *, boolean, boolean, etree_type *,
etree_type *));
extern void lang_section_in_phdr PARAMS ((const char *));
+extern void lang_add_nocrossref PARAMS ((struct lang_nocrossref *));
#endif
<BOTH,SCRIPT>"SHORT" { RTOKEN( SHORT);}
<BOTH,SCRIPT>"BYTE" { RTOKEN( BYTE);}
<BOTH,SCRIPT>"NOFLOAT" { RTOKEN(NOFLOAT);}
+<BOTH,SCRIPT>"NOCROSSREFS" { RTOKEN(NOCROSSREFS);}
<EXPRESSION,BOTH,SCRIPT>"NOLOAD" { RTOKEN(NOLOAD);}
<EXPRESSION,BOTH,SCRIPT>"DSECT" { RTOKEN(DSECT);}
<EXPRESSION,BOTH,SCRIPT>"COPY" { RTOKEN(COPY);}
lang_map ();
if (command_line.cref)
output_cref (config.map_file != NULL ? config.map_file : stdout);
+ if (nocrossref_list != NULL)
+ check_nocrossrefs ();
/* Even if we're producing relocateable output, some non-fatal errors should
be reported in the exit status. (What non-fatal errors, if any, do we
if (! info.found)
einfo ("%B: %s\n", abfd, warning);
+
+ if (entry == NULL)
+ free (asymbols);
}
return true;
bfd_is_und_section (section) ? "reference to" : "definition of",
name);
- if (command_line.cref)
+ if (command_line.cref || nocrossref_list != NULL)
add_cref (name, abfd, section, value);
return true;
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