OpenBSD-4.6/gnu/usr.bin/ld/warnings.c
/* * $OpenBSD: warnings.c,v 1.12 2008/02/12 21:17:53 miod Exp $*/
/*
*/
#include <sys/param.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/file.h>
#include <sys/time.h>
#include <err.h>
#include <stdio.h>
#include <stdlib.h>
#include <fcntl.h>
#include <ar.h>
#include <ranlib.h>
#include <a.out.h>
#include <stab.h>
#include <string.h>
#if __STDC__
#include <stdarg.h>
#else
#include <varargs.h>
#endif
#include "ld.h"
static int reported_undefineds;
/*
* Print the filename of ENTRY on OUTFILE (a stdio stream),
* and then a newline.
*/
void
prline_file_name(struct file_entry *entry, FILE *outfile)
{
print_file_name (entry, outfile);
fprintf (outfile, "\n");
}
/*
* Print the filename of ENTRY on OUTFILE (a stdio stream).
*/
void
print_file_name(struct file_entry *entry, FILE *outfile)
{
if (entry == NULL) {
fprintf (outfile, "NULL");
}
if (entry->superfile) {
print_file_name (entry->superfile, outfile);
fprintf (outfile, "(%s)", entry->filename);
} else
fprintf (outfile, "%s", entry->filename);
}
/*
* Return the filename of entry as a string (malloc'd for the purpose)
*/
char *
get_file_name(struct file_entry *entry)
{
char *result, *supfile;
size_t len;
if (entry == NULL) {
return (char *)strdup("NULL");
}
if (entry->superfile) {
supfile = get_file_name(entry->superfile);
len = strlen(supfile) + 1 + strlen(entry->filename) + 2;
result = (char *)
xmalloc(len);
(void)snprintf(result, len, "%s(%s)", supfile,
entry->filename);
free(supfile);
} else {
result = (char *)xstrdup(entry->filename);
}
return result;
}
/* Print a complete or partial map of the output file. */
static void describe_file_sections(struct file_entry *, void *);
static void list_file_locals(struct file_entry *, void *);
void
print_symbols(FILE *outfile)
{
fprintf(outfile, "\nFiles:\n\n");
each_file(describe_file_sections, (void *)outfile);
fprintf(outfile, "\nGlobal symbols:\n\n");
FOR_EACH_SYMBOL(i, sp) {
fprintf(outfile, " %s: ", sp->name);
if (!(sp->flags & GS_REFERENCED))
fprintf(outfile, "unreferenced");
else if (sp->so_defined)
fprintf(outfile, "sodefined");
else if (!sp->defined)
fprintf(outfile, "undefined");
else if (sp->defined == (N_UNDF|N_EXT))
fprintf(outfile, "common: size %#x", sp->common_size);
else
fprintf(outfile, "type %d, value %#lx, size %#x",
sp->defined, sp->value, sp->size);
if (sp->alias)
fprintf(outfile, ", aliased to %s", sp->alias->name);
fprintf(outfile, "\n");
} END_EACH_SYMBOL;
each_file(list_file_locals, (void *)outfile);
}
static void
describe_file_sections(struct file_entry *entry, void *arg)
{
FILE *outfile = arg;
fprintf(outfile, " ");
print_file_name(entry, outfile);
if (entry->flags & (E_JUST_SYMS | E_DYNAMIC))
fprintf(outfile, " symbols only\n");
else
fprintf(outfile, " text %x(%x), data %x(%x), bss %x(%x) hex\n",
entry->text_start_address, entry->header.a_text,
entry->data_start_address, entry->header.a_data,
entry->bss_start_address, entry->header.a_bss);
}
static void
list_file_locals(struct file_entry *entry, void *arg)
{
FILE *outfile = arg;
struct localsymbol *lsp, *lspend;
entry->strings = (char *)alloca(entry->string_size);
read_entry_strings (file_open(entry), entry);
fprintf (outfile, "\nLocal symbols of ");
print_file_name (entry, outfile);
fprintf (outfile, ":\n\n");
lspend = entry->symbols + entry->nsymbols;
for (lsp = entry->symbols; lsp < lspend; lsp++) {
struct nlist *p = &lsp->nzlist.nlist;
/*
* If this is a definition,
* update it if necessary by this file's start address.
*/
if (!(p->n_type & (N_STAB | N_EXT)))
fprintf(outfile, " %s: 0x%lx\n",
entry->strings + p->n_un.n_strx, p->n_value);
}
entry->strings = 0; /* All done with them. */
}
/* Static vars for do_warnings and subroutines of it */
static int list_unresolved_refs; /* List unresolved refs */
static int list_multiple_defs; /* List multiple definitions */
static struct line_debug_entry *init_debug_scan(int, struct file_entry *);
static int next_debug_entry(int, struct line_debug_entry *);
/*
* Structure for communication between do_file_warnings and it's
* helper routines. Will in practice be an array of three of these:
* 0) Current line, 1) Next line, 2) Source file info.
*/
struct line_debug_entry
{
int line;
char *filename;
struct localsymbol *sym;
};
/*
* Helper routines for do_file_warnings.
*/
/*
* Return an integer less than, equal to, or greater than 0 as per the
* relation between the two relocation entries. Used by qsort.
*/
static int
reloc_cmp(const void *arg1, const void *arg2)
{
const struct relocation_info *rel1 = arg1;
const struct relocation_info *rel2 = arg2;
return RELOC_ADDRESS(rel1) - RELOC_ADDRESS(rel2);
}
/*
* Moves to the next debugging symbol in the file. USE_DATA_SYMBOLS
* determines the type of the debugging symbol to look for (DSLINE or
* SLINE). STATE_POINTER keeps track of the old and new locatiosn in
* the file. It assumes that state_pointer[1] is valid; ie
* that it.sym points into some entry in the symbol table. If
* state_pointer[1].sym == 0, this routine should not be called.
*/
static int
next_debug_entry(int use_data_symbols, struct line_debug_entry state_pointer[3])
{
struct line_debug_entry *current = state_pointer,
*next = state_pointer + 1,
/* Used to store source file */
*source = state_pointer + 2;
struct file_entry *entry = (struct file_entry *)source->sym;
struct localsymbol *lspend = entry->symbols + entry->nsymbols;
current->sym = next->sym;
current->line = next->line;
current->filename = next->filename;
while (++(next->sym) < lspend) {
struct nlist *np = &next->sym->nzlist.nlist;
/*
* n_type is a char, and N_SOL, N_EINCL and N_BINCL are > 0x80,
* so may look negative...therefore, must mask to low bits
*/
switch (np->n_type & 0xff) {
case N_SLINE:
if (use_data_symbols)
continue;
next->line = np->n_desc;
return 1;
case N_DSLINE:
if (!use_data_symbols)
continue;
next->line = np->n_desc;
return 1;
#ifdef HAVE_SUN_STABS
case N_EINCL:
next->filename = source->filename;
continue;
#endif
case N_SO:
source->filename = np->n_un.n_strx + entry->strings;
source->line++;
#ifdef HAVE_SUN_STABS
case N_BINCL:
#endif
case N_SOL:
next->filename = np->n_un.n_strx + entry->strings;
default:
continue;
}
}
next->sym = (struct localsymbol *)0;
return 0;
}
/*
* Create a structure to save the state of a scan through the debug symbols.
* USE_DATA_SYMBOLS is set if we should be scanning for DSLINE's instead of
* SLINE's. ENTRY is the file entry which points at the symbols to use.
*/
static struct line_debug_entry *
init_debug_scan(int use_data_symbols, struct file_entry *entry)
{
struct localsymbol *lsp, *lspend;
struct line_debug_entry *state_pointer, *current, *next, *source;
state_pointer = (struct line_debug_entry *)
xmalloc(3 * sizeof(*state_pointer));
current = state_pointer,
next = state_pointer + 1,
source = state_pointer + 2; /* Used to store source file */
lspend = entry->symbols+entry->nsymbols;
for (lsp = entry->symbols; lsp < lspend; lsp++)
if (lsp->nzlist.nlist.n_type == N_SO)
break;
if (lsp >= lspend) {
/* I believe this translates to "We lose" */
current->filename = next->filename = entry->filename;
current->line = next->line = -1;
current->sym = next->sym = (struct localsymbol *)0;
return state_pointer;
}
next->line = source->line = 0;
next->filename = source->filename
= (lsp->nzlist.nlist.n_un.n_strx + entry->strings);
source->sym = (struct localsymbol *)entry;
next->sym = lsp;
/* To setup next */
next_debug_entry(use_data_symbols, state_pointer);
if (!next->sym) { /* No line numbers for this section; */
/* setup output results as appropriate */
if (source->line) {
current->filename = source->filename = entry->filename;
current->line = -1; /* Don't print lineno */
} else {
current->filename = source->filename;
current->line = 0;
}
return state_pointer;
}
/* To setup current */
next_debug_entry(use_data_symbols, state_pointer);
return state_pointer;
}
/*
* Takes an ADDRESS (in either text or data space) and a STATE_POINTER which
* describes the current location in the implied scan through the debug
* symbols within the file which ADDRESS is within, and returns the source
* line number which corresponds to ADDRESS.
*/
static int
address_to_line(unsigned long address, struct line_debug_entry state_pointer[3])
{
struct line_debug_entry *current, *next, *tmp_pointer;
int use_data_symbols;
current = state_pointer;
next = state_pointer + 1;
if (next->sym)
use_data_symbols =
(next->sym->nzlist.nlist.n_type & N_TYPE) == N_DATA;
else
return current->line;
/* Go back to the beginning if we've already passed it. */
if (current->sym->nzlist.nlist.n_value > address) {
tmp_pointer = init_debug_scan(use_data_symbols,
(struct file_entry *)
((state_pointer + 2)->sym));
state_pointer[0] = tmp_pointer[0];
state_pointer[1] = tmp_pointer[1];
state_pointer[2] = tmp_pointer[2];
free(tmp_pointer);
}
/* If we're still in a bad way, return -1, meaning invalid line. */
if (current->sym->nzlist.nlist.n_value > address)
return -1;
while (next->sym
&& next->sym->nzlist.nlist.n_value <= address
&& next_debug_entry(use_data_symbols, state_pointer));
return current->line;
}
/* Macros for manipulating bitvectors. */
#define BIT_SET_P(bv, index) ((bv)[(index) >> 3] & 1 << ((index) & 0x7))
#define SET_BIT(bv, index) ((bv)[(index) >> 3] |= 1 << ((index) & 0x7))
/*
* This routine will scan through the relocation data of file ENTRY, printing
* out references to undefined symbols and references to symbols defined in
* files with N_WARNING symbols. If DATA_SEGMENT is non-zero, it will scan
* the data relocation segment (and use N_DSLINE symbols to track line
* number); otherwise it will scan the text relocation segment. Warnings
* will be printed on the output stream OUTFILE. Eventually, every nlist
* symbol mapped through will be marked in the NLIST_BITVECTOR, so we don't
* repeat ourselves when we scan the nlists themselves.
*/
static void
do_relocation_warnings(struct file_entry *entry, int data_segment,
FILE *outfile, unsigned char *nlist_bitvector)
{
struct relocation_info *rp, *erp;
int start_of_segment;
struct localsymbol *start_of_syms;
struct line_debug_entry *state_pointer, *current;
/* Assigned to generally static values; should not be written into. */
char *errfmt;
/*
* Assigned to alloca'd values cand copied into; should be freed when
* done.
*/
char *errmsg;
int invalidate_line_number;
rp = data_segment ? entry->datarel : entry->textrel;
erp = data_segment ? (rp + entry->ndatarel) : (rp + entry->ntextrel);
start_of_syms = entry->symbols;
start_of_segment = (data_segment ?
entry->data_start_address :
entry->text_start_address);
state_pointer = init_debug_scan(data_segment != 0, entry);
current = state_pointer;
/*
* We need to sort the relocation info here. Sheesh, so much effort
* for one lousy error optimization.
*/
qsort(rp, erp - rp, sizeof(rp[0]), reloc_cmp);
for (; rp < erp; rp++) {
struct localsymbol *lsp;
symbol *g;
/*
* If the relocation isn't resolved through a symbol, continue.
*/
if (!RELOC_EXTERN_P(rp))
continue;
lsp = &entry->symbols[RELOC_SYMBOL(rp)];
/*
* Local symbols shouldn't ever be used by relocation info,
* so the next should be safe. This is, of course, wrong.
* References to local BSS symbols can be the targets of
* relocation info, and they can (must) be resolved through
* symbols. However, these must be defined properly, (the
* assembler would have caught it otherwise), so we can
* ignore these cases.
*/
if ((g = lsp->symbol) == NULL)
continue;
if (!(lsp->nzlist.nz_type & N_EXT) &&
!SET_ELEMENT_P(lsp->nzlist.nz_type)) {
warnx("internal error: `%s' N_EXT not set", g->name);
continue;
}
errmsg = 0;
if (!g->defined && !g->so_defined && list_unresolved_refs) {
/* Mark as being noted by relocation warning pass. */
SET_BIT(nlist_bitvector, lsp - start_of_syms);
if (g->undef_refs == 0)
reported_undefineds++;
if (g->undef_refs >= MAX_UREFS_PRINTED)
/* Listed too many */
continue;
/* Undefined symbol which we should mention */
if (++(g->undef_refs) == MAX_UREFS_PRINTED) {
errfmt = "More undefined symbol %s refs follow";
invalidate_line_number = 1;
} else {
errfmt =
"Undefined symbol `%s' referenced from %s segment";
invalidate_line_number = 0;
}
} else { /* Defined */
/* Potential symbol warning here */
if (!g->warning)
continue;
if (BIT_SET_P(nlist_bitvector, lsp - start_of_syms))
continue;
/* Mark as being noted by relocation warning pass. */
SET_BIT(nlist_bitvector, lsp - start_of_syms);
errfmt = 0;
errmsg = g->warning;
invalidate_line_number = 0;
}
/* If errfmt == 0, errmsg has already been defined. */
if (errfmt != 0) {
char *nm;
size_t len;
nm = g->name;
len = strlen(errfmt) + strlen(nm) + 1;
errmsg = (char *)
xmalloc(len);
snprintf(errmsg, len, errfmt, nm,
data_segment?"data":"text");
if (nm != g->name)
free(nm);
}
address_to_line(RELOC_ADDRESS(rp) + start_of_segment,
state_pointer);
if (current->line >= 0)
fprintf(outfile, "%s:%d: %s\n",
current->filename,
invalidate_line_number ? 0 : current->line,
errmsg);
else
fprintf(outfile, "%s: %s\n", current->filename, errmsg);
if (errfmt != 0)
free(errmsg);
}
free(state_pointer);
}
/*
* Print on OUTFILE a list of all warnings generated by references and/or
* definitions in the file ENTRY. List source file and line number if
* possible, just the .o file if not.
*/
static void
do_file_warnings(struct file_entry *entry, void *arg)
{
int nsym;
int i;
char *errfmt, *file_name;
int line_number;
int dont_allow_symbol_name;
u_char *nlist_bitvector;
struct line_debug_entry *text_scan, *data_scan;
FILE *outfile = arg;
nsym = entry->nsymbols;
nlist_bitvector = (u_char *)alloca((nsym >> 3) + 1);
bzero(nlist_bitvector, (nsym >> 3) + 1);
/* Read in the strings */
entry->strings = (char *)alloca(entry->string_size);
read_entry_strings(file_open(entry), entry);
if (!(entry->flags & E_DYNAMIC)) {
/* Do text warnings based on a scan through the reloc info. */
do_relocation_warnings(entry, 0, outfile, nlist_bitvector);
/* Do data warnings based on a scan through the reloc info. */
do_relocation_warnings(entry, 1, outfile, nlist_bitvector);
}
/*
* Scan through all of the nlist entries in this file and pick up
* anything that the scan through the relocation stuff didn't.
*/
text_scan = init_debug_scan(0, entry);
data_scan = init_debug_scan(1, entry);
for (i = 0; i < nsym; i++) {
struct nlist *np;
symbol *g;
g = entry->symbols[i].symbol;
np = &entry->symbols[i].nzlist.nlist;
if (g == NULL)
continue;
if (!(np->n_type & N_EXT) && !SET_ELEMENT_P(np->n_type)) {
warnx("internal error: `%s' N_EXT not set", g->name);
continue;
}
if (!(g->flags & GS_REFERENCED)) {
#if 0
/* Check for undefined shobj symbols */
struct localsymbol *lsp;
int type;
for (lsp = g->sorefs; lsp; lsp = lsp->next) {
type = lsp->nzlist.nz_type;
if ((type & N_EXT) &&
type != (N_UNDF | N_EXT)) {
break;
}
}
if (type == (N_UNDF | N_EXT)) {
fprintf(stderr,
"Undefined symbol %s referenced from %s\n",
g->name,
get_file_name(entry));
}
#endif
continue;
}
dont_allow_symbol_name = 0;
if (list_multiple_defs && g->mult_defs) {
errfmt = "Definition of symbol `%s' (multiply defined)";
switch (np->n_type) {
case N_TEXT | N_EXT:
line_number =
address_to_line(np->n_value, text_scan);
file_name = text_scan[0].filename;
break;
case N_DATA | N_EXT:
line_number =
address_to_line(np->n_value, data_scan);
file_name = data_scan[0].filename;
break;
case N_SETA | N_EXT:
case N_SETT | N_EXT:
case N_SETD | N_EXT:
case N_SETB | N_EXT:
if (g->mult_defs == 2)
continue;
errfmt =
"First set element definition of symbol `%s' (multiply defined)";
line_number = -1;
break;
case N_SIZE | N_EXT:
errfmt =
"Size element definition of symbol `%s' (multiply defined)";
line_number = -1;
break;
case N_INDR | N_EXT:
errfmt =
"Alias definition of symbol `%s' (multiply defined)";
line_number = -1;
break;
case N_UNDF | N_EXT:
/* Don't print out multiple defs at references.*/
continue;
default:
warnx("%s: unexpected multiple definitions "
"of symbol `%s', type %#x",
get_file_name(entry),
g->name, np->n_type);
line_number = -1;
break;
}
} else if (BIT_SET_P(nlist_bitvector, i)) {
continue;
} else if (list_unresolved_refs &&
!g->defined && !g->so_defined) {
if (g->undef_refs == 0)
reported_undefineds++;
if (g->undef_refs >= MAX_UREFS_PRINTED)
continue;
if (++(g->undef_refs) == MAX_UREFS_PRINTED)
errfmt = "More undefined `%s' refs follow";
else
errfmt = "Undefined symbol `%s' referenced";
line_number = -1;
} else if (g->def_lsp && g->def_lsp->entry != entry &&
!(entry->flags & E_DYNAMIC) &&
g->def_lsp->entry->flags & E_SECONDCLASS) {
if (g->undef_refs == 0)
reported_undefineds++;
if (g->undef_refs >= MAX_UREFS_PRINTED)
continue;
if (++(g->undef_refs) == MAX_UREFS_PRINTED) {
errfmt = "More undefined `%s' refs follow";
line_number = -1;
} else {
fprintf(outfile,
"%s: Undefined symbol `%s' referenced (use %s ?)\n",
get_file_name(entry),
g->name,
g->def_lsp->entry->local_sym_name);
continue;
}
} else if (g->warning) {
/*
* There are two cases in which we don't want to do
* this. The first is if this is a definition instead
* of a reference. The second is if it's the reference
* used by the warning stabs itself.
*/
if (np->n_type != (N_EXT | N_UNDF) ||
(entry->symbols[i].flags & LS_WARNING))
continue;
errfmt = g->warning;
line_number = -1;
dont_allow_symbol_name = 1;
} else
continue;
if (line_number == -1)
fprintf(outfile, "%s: ", get_file_name(entry));
else
fprintf(outfile, "%s:%d: ", file_name, line_number);
if (dont_allow_symbol_name)
fprintf(outfile, "%s", errfmt);
else
fprintf(outfile, errfmt, g->name);
fputc('\n', outfile);
}
free(text_scan);
free(data_scan);
entry->strings = 0; /* Since it will disappear anyway. */
}
int
do_warnings(FILE *outfile)
{
list_unresolved_refs = !relocatable_output &&
( (undefined_global_sym_count - undefined_weak_sym_count) > 0
|| undefined_shobj_sym_count
);
list_multiple_defs = multiple_def_count != 0;
if (!(list_unresolved_refs ||
list_warning_symbols ||
list_multiple_defs))
/* No need to run this routine */
return 1;
if (entry_symbol && !entry_symbol->defined)
fprintf(outfile, "Undefined entry symbol `%s'\n",
entry_symbol->name);
each_file(do_file_warnings, (void *)outfile);
if (list_unresolved_refs &&
reported_undefineds !=
(undefined_global_sym_count - undefined_weak_sym_count))
warnx("internal consistency check failure: "
"# undefined symbols %d, accounted for %d",
(undefined_global_sym_count - undefined_weak_sym_count),
reported_undefineds);
if (list_unresolved_refs || list_multiple_defs)
return 0;
return 1;
}