diff options
| -rw-r--r-- | ld/ChangeLog | 29 | ||||
| -rw-r--r-- | ld/NEWS | 2 | ||||
| -rw-r--r-- | ld/ld.texinfo | 18 | ||||
| -rw-r--r-- | ld/ldcref.c | 220 | ||||
| -rw-r--r-- | ld/ldgram.y | 34 | ||||
| -rw-r--r-- | ld/ldlang.c | 18 | ||||
| -rw-r--r-- | ld/ldlang.h | 40 | ||||
| -rw-r--r-- | ld/ldlex.l | 1 | ||||
| -rw-r--r-- | ld/ldmain.c | 7 |
9 files changed, 359 insertions, 10 deletions
diff --git a/ld/ChangeLog b/ld/ChangeLog index 6078513..706579f 100644 --- a/ld/ChangeLog +++ b/ld/ChangeLog @@ -1,5 +1,34 @@ 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. @@ -5,6 +5,8 @@ Changes since version 2.7: * 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. diff --git a/ld/ld.texinfo b/ld/ld.texinfo index 1034b1e..99450f6 100644 --- a/ld/ld.texinfo +++ b/ld/ld.texinfo @@ -2704,6 +2704,24 @@ the environment variable @code{GNUTARGET}, if available, to select the 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 diff --git a/ld/ldcref.c b/ld/ldcref.c index 2aceb1f..369cd62 100644 --- a/ld/ldcref.c +++ b/ld/ldcref.c @@ -18,7 +18,9 @@ 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., 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" @@ -28,6 +30,8 @@ Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ #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. */ @@ -71,6 +75,11 @@ static struct bfd_hash_entry *cref_hash_newfunc 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. */ @@ -325,3 +334,212 @@ output_one_cref (fp, h) 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); +} diff --git a/ld/ldgram.y b/ld/ldgram.y index 92ba5bc..1f16baa 100644 --- a/ld/ldgram.y +++ b/ld/ldgram.y @@ -75,6 +75,7 @@ static int error_index; 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 @@ -82,8 +83,9 @@ static int error_index; %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> '?' ':' @@ -112,7 +114,7 @@ static int error_index; %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 @@ -299,6 +301,10 @@ ifile_p1: { lang_add_map($3); } | INCLUDE filename { ldfile_open_command_file($2); } ifile_list END + | NOCROSSREFS '(' nocrossref_list ')' + { + lang_add_nocrossref ($3); + } ; input_list: @@ -569,6 +575,30 @@ floating_point_support: { 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 diff --git a/ld/ldlang.c b/ld/ldlang.c index ae844be..b7a0493 100644 --- a/ld/ldlang.c +++ b/ld/ldlang.c @@ -142,6 +142,7 @@ boolean lang_has_input_file = false; 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 */ @@ -3617,3 +3618,20 @@ lang_record_phdrs () 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; +} diff --git a/ld/ldlang.h b/ld/ldlang.h index 3d6a6f3..ee5b777 100644 --- a/ld/ldlang.h +++ b/ld/ldlang.h @@ -1,5 +1,5 @@ /* 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. @@ -96,6 +96,17 @@ typedef struct lang_output_statement_struct 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. */ @@ -120,7 +131,7 @@ typedef struct lang_output_section_statement_struct 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; @@ -243,9 +254,6 @@ typedef struct lang_input_statement_struct /* 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 @@ -335,6 +343,25 @@ struct lang_phdr 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; @@ -353,7 +380,7 @@ extern void lang_add_output PARAMS ((const char *, int from_script)); 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, @@ -431,5 +458,6 @@ extern void lang_new_phdr 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 @@ -256,6 +256,7 @@ NOCFILENAMECHAR [_a-zA-Z0-9\/\.\-\_\+\$\:\[\]\\\~] <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);} diff --git a/ld/ldmain.c b/ld/ldmain.c index 3d0f9fa..315ac0c 100644 --- a/ld/ldmain.c +++ b/ld/ldmain.c @@ -323,6 +323,8 @@ main (argc, argv) 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 @@ -1031,6 +1033,9 @@ warning_callback (info, warning, symbol, abfd, section, address) if (! info.found) einfo ("%B: %s\n", abfd, warning); + + if (entry == NULL) + free (asymbols); } return true; @@ -1241,7 +1246,7 @@ notice (info, name, abfd, section, value) 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; |