RFC: Access TLS symbols without DWARF debuginfo

Jan Kratochvil
2006-08-25T02:24:33Z

[-- Attachment #1: Type: text/plain, Size: 750 bytes --]

Hi,

https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=185337

currently if you have threaded (-lpthread) program compiled without debuginfo
"-g" and you try to access TLS symbol you will get:
(gdb) print thread_local
Cannot access memory at address 0x0

as gdb tries to resolve TLS-offset as absolute memory reference.

In fact it occurs if you try to access "errno" on -lpthread program with
debuginfo lower than -ggdb3.

Attached patch implements accessing them without the debuginfo suggestions as
not always such associatet debuginfo is available. It checks for
SYMBOL_BFD_SECTION (msymbol)->flags & SEC_THREAD_LOCAL
symbols, implements for them new `UNOP_MEMVAL_TLS' and reuses for them former
`dwarf_expr_tls_address'.

Regards,
Jan.

[-- Attachment #2: gdb-6.5-bz185337-resolve-tls-without-debuginfo.patch --]
[-- Type: text/plain, Size: 24159 bytes --]

Index: gdb/dwarf2loc.c
===================================================================
RCS file: /cvs/src/src/gdb/dwarf2loc.c,v
retrieving revision 1.33
diff -u -p -r1.33 dwarf2loc.c
--- gdb/dwarf2loc.c 17 Dec 2005 22:33:59 -0000 1.33
+++ gdb/dwarf2loc.c 25 Aug 2006 01:42:22 -0000
@@ -189,86 +189,8 @@ static CORE_ADDR
dwarf_expr_tls_address (void *baton, CORE_ADDR offset)
{
struct dwarf_expr_baton *debaton = (struct dwarf_expr_baton *) baton;
- volatile CORE_ADDR addr = 0;

- if (target_get_thread_local_address_p ()
- && gdbarch_fetch_tls_load_module_address_p (current_gdbarch))
- {
- ptid_t ptid = inferior_ptid;
- struct objfile *objfile = debaton->objfile;
- volatile struct gdb_exception ex;
-
- TRY_CATCH (ex, RETURN_MASK_ALL)
- {
- CORE_ADDR lm_addr;
-
- /* Fetch the load module address for this objfile. */
- lm_addr = gdbarch_fetch_tls_load_module_address (current_gdbarch,
- objfile);
- /* If it's 0, throw the appropriate exception. */
- if (lm_addr == 0)
- throw_error (TLS_LOAD_MODULE_NOT_FOUND_ERROR,
- _("TLS load module not found"));
-
- addr = target_get_thread_local_address (ptid, lm_addr, offset);
- }
- /* If an error occurred, print TLS related messages here. Otherwise,
- throw the error to some higher catcher. */
- if (ex.reason < 0)
- {
- int objfile_is_library = (objfile->flags & OBJF_SHARED);
-
- switch (ex.error)
- {
- case TLS_NO_LIBRARY_SUPPORT_ERROR:
- error (_("Cannot find thread-local variables in this thread library."));
- break;
- case TLS_LOAD_MODULE_NOT_FOUND_ERROR:
- if (objfile_is_library)
- error (_("Cannot find shared library `%s' in dynamic"
- " linker's load module list"), objfile->name);
- else
- error (_("Cannot find executable file `%s' in dynamic"
- " linker's load module list"), objfile->name);
- break;
- case TLS_NOT_ALLOCATED_YET_ERROR:
- if (objfile_is_library)
- error (_("The inferior has not yet allocated storage for"
- " thread-local variables in\n"
- "the shared library `%s'\n"
- "for %s"),
- objfile->name, target_pid_to_str (ptid));
- else
- error (_("The inferior has not yet allocated storage for"
- " thread-local variables in\n"
- "the executable `%s'\n"
- "for %s"),
- objfile->name, target_pid_to_str (ptid));
- break;
- case TLS_GENERIC_ERROR:
- if (objfile_is_library)
- error (_("Cannot find thread-local storage for %s, "
- "shared library %s:\n%s"),
- target_pid_to_str (ptid),
- objfile->name, ex.message);
- else
- error (_("Cannot find thread-local storage for %s, "
- "executable file %s:\n%s"),
- target_pid_to_str (ptid),
- objfile->name, ex.message);
- break;
- default:
- throw_exception (ex);
- break;
- }
- }
- }
- /* It wouldn't be wrong here to try a gdbarch method, too; finding
- TLS is an ABI-specific thing. But we don't do that yet. */
- else
- error (_("Cannot find thread-local variables on this target"));
-
- return addr;
+ return target_translate_tls_address (debaton->objfile, offset);
}

/* Evaluate a location description, starting at DATA and with length
Index: gdb/eval.c
===================================================================
RCS file: /cvs/src/src/gdb/eval.c,v
retrieving revision 1.63
diff -u -p -r1.63 eval.c
--- gdb/eval.c 25 Jul 2006 04:24:50 -0000 1.63
+++ gdb/eval.c 25 Aug 2006 01:42:24 -0000
@@ -2019,6 +2019,18 @@ evaluate_subexp_standard (struct type *e
return value_at_lazy (exp->elts[pc + 1].type,
value_as_address (arg1));

+ case UNOP_MEMVAL_TLS:
+ (*pos) += 3;
+ arg1 = evaluate_subexp (expect_type, exp, pos, noside);
+ if (noside == EVAL_SKIP)
+ goto nosideret;
+ if (noside == EVAL_AVOID_SIDE_EFFECTS)
+ return value_zero (exp->elts[pc + 2].type, lval_memory);
+ else
+ return value_at_lazy_tls (exp->elts[pc + 2].type,
+ value_as_address (arg1),
+ exp->elts[pc + 1].objfile);
+
case UNOP_PREINCREMENT:
arg1 = evaluate_subexp (expect_type, exp, pos, noside);
if (noside == EVAL_SKIP || noside == EVAL_AVOID_SIDE_EFFECTS)
Index: gdb/expprint.c
===================================================================
RCS file: /cvs/src/src/gdb/expprint.c,v
retrieving revision 1.24
diff -u -p -r1.24 expprint.c
--- gdb/expprint.c 7 Aug 2006 03:30:54 -0000 1.24
+++ gdb/expprint.c 25 Aug 2006 01:42:25 -0000
@@ -31,6 +31,7 @@
#include "target.h"
#include "gdb_string.h"
#include "block.h"
+#include "objfiles.h"

#ifdef HAVE_CTYPE_H
#include <ctype.h>
@@ -414,6 +415,33 @@ print_subexp_standard (struct expression
fputs_filtered (")", stream);
return;

+ case UNOP_MEMVAL_TLS:
+ (*pos) += 3;
+ if ((int) prec > (int) PREC_PREFIX)
+ fputs_filtered ("(", stream);
+ if (TYPE_CODE (exp->elts[pc + 2].type) == TYPE_CODE_FUNC &&
+ exp->elts[pc + 4].opcode == OP_LONG)
+ {
+ /* We have a minimal symbol fn, probably. It's encoded
+ as a UNOP_MEMVAL (function-type) of an OP_LONG (int, address).
+ Swallow the OP_LONG (including both its opcodes); ignore
+ its type; print the value in the type of the MEMVAL. */
+ (*pos) += 4;
+ val = value_at_lazy (exp->elts[pc + 2].type,
+ (CORE_ADDR) exp->elts[pc + 6].longconst);
+ value_print (val, stream, 0, Val_no_prettyprint);
+ }
+ else
+ {
+ fputs_filtered ("{", stream);
+ type_print (exp->elts[pc + 2].type, "", stream, 0);
+ fputs_filtered ("} ", stream);
+ print_subexp (exp, pos, stream, PREC_PREFIX);
+ }
+ if ((int) prec > (int) PREC_PREFIX)
+ fputs_filtered (")", stream);
+ return;
+
case BINOP_ASSIGN_MODIFY:
opcode = exp->elts[pc + 1].opcode;
(*pos) += 2;
@@ -694,6 +722,8 @@ op_name_standard (enum exp_opcode opcode
return "UNOP_CAST";
case UNOP_MEMVAL:
return "UNOP_MEMVAL";
+ case UNOP_MEMVAL_TLS:
+ return "UNOP_MEMVAL_TLS";
case UNOP_NEG:
return "UNOP_NEG";
case UNOP_LOGICAL_NOT:
@@ -999,6 +1029,16 @@ dump_subexp_body_standard (struct expres
fprintf_filtered (stream, ")");
elt = dump_subexp (exp, stream, elt + 2);
break;
+ case UNOP_MEMVAL_TLS:
+ fprintf_filtered (stream, "TLS type @");
+ gdb_print_host_address (exp->elts[elt + 1].type, stream);
+ fprintf_filtered (stream, " (__thread /* \"%s\" */ ",
+ (exp->elts[elt].objfile == NULL ? "(null)"
+ : exp->elts[elt].objfile->name));
+ type_print (exp->elts[elt + 1].type, NULL, stream, 0);
+ fprintf_filtered (stream, ")");
+ elt = dump_subexp (exp, stream, elt + 3);
+ break;
case OP_TYPE:
fprintf_filtered (stream, "Type @");
gdb_print_host_address (exp->elts[elt].type, stream);
Index: gdb/expression.h
===================================================================
RCS file: /cvs/src/src/gdb/expression.h,v
retrieving revision 1.18
diff -u -p -r1.18 expression.h
--- gdb/expression.h 17 Dec 2005 22:33:59 -0000 1.18
+++ gdb/expression.h 25 Aug 2006 01:42:26 -0000
@@ -234,6 +234,13 @@ enum exp_opcode
following subexpression. */
UNOP_MEMVAL,

+ /* UNOP_MEMVAL_TLS is followed by a `struct objfile' pointer in the next
+ exp_element and a type pointer in the following exp_element.
+ With another UNOP_MEMVAL_TLS at the end, this makes four exp_elements.
+ It casts the contents of the word offsetted by the value of the
+ following subexpression from the TLS specified by `struct objfile'. */
+ UNOP_MEMVAL_TLS,
+
/* UNOP_... operate on one value from a following subexpression
and replace it with a result. They take no immediate arguments. */

@@ -360,6 +367,7 @@ union exp_element
struct type *type;
struct internalvar *internalvar;
struct block *block;
+ struct objfile *objfile;
};

struct expression
Index: gdb/parse.c
===================================================================
RCS file: /cvs/src/src/gdb/parse.c,v
retrieving revision 1.53
diff -u -p -r1.53 parse.c
--- gdb/parse.c 6 Jul 2006 14:00:48 -0000 1.53
+++ gdb/parse.c 25 Aug 2006 01:42:29 -0000
@@ -53,6 +53,7 @@
#include "gdb_assert.h"
#include "block.h"
#include "source.h"
+#include "objfiles.h"

/* Standard set of definitions for printing, dumping, prefixifying,
* and evaluating expressions. */
@@ -219,6 +220,15 @@ write_exp_elt_block (struct block *b)
}

void
+write_exp_elt_objfile (struct objfile *objfile)
+{
+ union exp_element tmp;
+ memset (&tmp, 0, sizeof (union exp_element));
+ tmp.objfile = objfile;
+ write_exp_elt (tmp);
+}
+
+void
write_exp_elt_longcst (LONGEST expelt)
{
union exp_element tmp;
@@ -378,6 +388,9 @@ write_exp_bitstring (struct stoken str)
static struct type *msym_text_symbol_type;
static struct type *msym_data_symbol_type;
static struct type *msym_unknown_symbol_type;
+static struct type *msym_text_tls_symbol_type;
+static struct type *msym_data_tls_symbol_type;
+static struct type *msym_unknown_tls_symbol_type;

void
write_exp_msymbol (struct minimal_symbol *msymbol,
@@ -385,6 +398,8 @@ write_exp_msymbol (struct minimal_symbol
struct type *data_symbol_type)
{
CORE_ADDR addr;
+ int tls = SYMBOL_BFD_SECTION (msymbol)->flags & SEC_THREAD_LOCAL;
+ enum exp_opcode opcode = tls ? UNOP_MEMVAL_TLS : UNOP_MEMVAL;

write_exp_elt_opcode (OP_LONG);
/* Let's make the type big enough to hold a 64-bit address. */
@@ -397,27 +412,49 @@ write_exp_msymbol (struct minimal_symbol

write_exp_elt_opcode (OP_LONG);

- write_exp_elt_opcode (UNOP_MEMVAL);
+ write_exp_elt_opcode (opcode);
+
+ if (opcode == UNOP_MEMVAL_TLS)
+ {
+ bfd *bfd = SYMBOL_BFD_SECTION (msymbol)->owner;
+ struct objfile *ofp;
+
+ ALL_OBJFILES (ofp)
+ if (ofp->obfd == bfd)
+ break;
+ write_exp_elt_objfile (ofp);
+ }
+
switch (msymbol->type)
{
case mst_text:
case mst_file_text:
case mst_solib_trampoline:
- write_exp_elt_type (msym_text_symbol_type);
+ if (tls)
+ write_exp_elt_type (msym_text_tls_symbol_type);
+ else
+ write_exp_elt_type (msym_text_symbol_type);
break;

case mst_data:
case mst_file_data:
case mst_bss:
case mst_file_bss:
- write_exp_elt_type (msym_data_symbol_type);
+ if (tls)
+ write_exp_elt_type (msym_data_tls_symbol_type);
+ else
+ write_exp_elt_type (msym_data_symbol_type);
break;

default:
- write_exp_elt_type (msym_unknown_symbol_type);
+ if (tls)
+ write_exp_elt_type (msym_unknown_tls_symbol_type);
+ else
+ write_exp_elt_type (msym_unknown_symbol_type);
break;
}
- write_exp_elt_opcode (UNOP_MEMVAL);
+
+ write_exp_elt_opcode (opcode);
}
\f
/* Recognize tokens that start with '$'. These include:
@@ -904,6 +941,11 @@ operator_length_standard (struct express
args = 1;
break;

+ case UNOP_MEMVAL_TLS:
+ oplen = 4;
+ args = 1;
+ break;
+
case UNOP_ABS:
case UNOP_CAP:
case UNOP_CHR:
@@ -1341,6 +1383,17 @@ build_parse (void)
init_type (TYPE_CODE_INT, 1, 0,
"<variable (not text or data), no debug info>",
NULL);
+
+ msym_text_tls_symbol_type =
+ init_type (TYPE_CODE_FUNC, 1, 0, "<TLS-based text variable, no debug info>", NULL);
+ TYPE_TARGET_TYPE (msym_text_tls_symbol_type) = builtin_type_int;
+ msym_data_tls_symbol_type =
+ init_type (TYPE_CODE_INT, TARGET_INT_BIT / HOST_CHAR_BIT, 0,
+ "<TLS-based data variable, no debug info>", NULL);
+ msym_unknown_tls_symbol_type =
+ init_type (TYPE_CODE_INT, 1, 0,
+ "<TLS-based variable (not text or data), no debug info>",
+ NULL);
}

/* This function avoids direct calls to fprintf
Index: gdb/parser-defs.h
===================================================================
RCS file: /cvs/src/src/gdb/parser-defs.h,v
retrieving revision 1.20
diff -u -p -r1.20 parser-defs.h
--- gdb/parser-defs.h 17 Dec 2005 22:34:01 -0000 1.20
+++ gdb/parser-defs.h 25 Aug 2006 01:42:30 -0000
@@ -131,6 +131,8 @@ extern void write_exp_bitstring (struct

extern void write_exp_elt_block (struct block *);

+extern void write_exp_elt_objfile (struct objfile *objfile);
+
extern void write_exp_msymbol (struct minimal_symbol *,
struct type *, struct type *);

Index: gdb/target.c
===================================================================
RCS file: /cvs/src/src/gdb/target.c,v
retrieving revision 1.124
diff -u -p -r1.124 target.c
--- gdb/target.c 16 Aug 2006 18:31:03 -0000 1.124
+++ gdb/target.c 25 Aug 2006 01:42:38 -0000
@@ -39,6 +39,7 @@
#include "regcache.h"
#include "gdb_assert.h"
#include "gdbcore.h"
+#include "exceptions.h"

static void target_info (char *, int);

@@ -755,6 +756,92 @@ pop_target (void)
internal_error (__FILE__, __LINE__, _("failed internal consistency check"));
}

+/* Using the objfile specified in BATON, find the address for the
+ current thread's thread-local storage with offset OFFSET. */
+CORE_ADDR
+target_translate_tls_address (struct objfile *objfile, CORE_ADDR offset)
+{
+ volatile CORE_ADDR addr = 0;
+
+ if (target_get_thread_local_address_p ()
+ && gdbarch_fetch_tls_load_module_address_p (current_gdbarch))
+ {
+ ptid_t ptid = inferior_ptid;
+ volatile struct gdb_exception ex;
+
+ TRY_CATCH (ex, RETURN_MASK_ALL)
+ {
+ CORE_ADDR lm_addr;
+
+ /* Fetch the load module address for this objfile. */
+ lm_addr = gdbarch_fetch_tls_load_module_address (current_gdbarch,
+ objfile);
+ /* If it's 0, throw the appropriate exception. */
+ if (lm_addr == 0)
+ throw_error (TLS_LOAD_MODULE_NOT_FOUND_ERROR,
+ _("TLS load module not found"));
+
+ addr = target_get_thread_local_address (ptid, lm_addr, offset);
+ }
+ /* If an error occurred, print TLS related messages here. Otherwise,
+ throw the error to some higher catcher. */
+ if (ex.reason < 0)
+ {
+ int objfile_is_library = (objfile->flags & OBJF_SHARED);
+
+ switch (ex.error)
+ {
+ case TLS_NO_LIBRARY_SUPPORT_ERROR:
+ error (_("Cannot find thread-local variables in this thread library."));
+ break;
+ case TLS_LOAD_MODULE_NOT_FOUND_ERROR:
+ if (objfile_is_library)
+ error (_("Cannot find shared library `%s' in dynamic"
+ " linker's load module list"), objfile->name);
+ else
+ error (_("Cannot find executable file `%s' in dynamic"
+ " linker's load module list"), objfile->name);
+ break;
+ case TLS_NOT_ALLOCATED_YET_ERROR:
+ if (objfile_is_library)
+ error (_("The inferior has not yet allocated storage for"
+ " thread-local variables in\n"
+ "the shared library `%s'\n"
+ "for %s"),
+ objfile->name, target_pid_to_str (ptid));
+ else
+ error (_("The inferior has not yet allocated storage for"
+ " thread-local variables in\n"
+ "the executable `%s'\n"
+ "for %s"),
+ objfile->name, target_pid_to_str (ptid));
+ break;
+ case TLS_GENERIC_ERROR:
+ if (objfile_is_library)
+ error (_("Cannot find thread-local storage for %s, "
+ "shared library %s:\n%s"),
+ target_pid_to_str (ptid),
+ objfile->name, ex.message);
+ else
+ error (_("Cannot find thread-local storage for %s, "
+ "executable file %s:\n%s"),
+ target_pid_to_str (ptid),
+ objfile->name, ex.message);
+ break;
+ default:
+ throw_exception (ex);
+ break;
+ }
+ }
+ }
+ /* It wouldn't be wrong here to try a gdbarch method, too; finding
+ TLS is an ABI-specific thing. But we don't do that yet. */
+ else
+ error (_("Cannot find thread-local variables on this target"));
+
+ return addr;
+}
+
#undef MIN
#define MIN(A, B) (((A) <= (B)) ? (A) : (B))

Index: gdb/target.h
===================================================================
RCS file: /cvs/src/src/gdb/target.h,v
retrieving revision 1.87
diff -u -p -r1.87 target.h
--- gdb/target.h 15 Aug 2006 18:46:25 -0000 1.87
+++ gdb/target.h 25 Aug 2006 01:42:40 -0000
@@ -1131,6 +1131,9 @@ extern void target_preopen (int);

extern void pop_target (void);

+extern CORE_ADDR target_translate_tls_address (struct objfile *objfile,
+ CORE_ADDR offset);
+
/* Struct section_table maps address ranges to file sections. It is
mostly used with BFD files, but can be used without (e.g. for handling
raw disks, or files not in formats handled by BFD). */
Index: gdb/valops.c
===================================================================
RCS file: /cvs/src/src/gdb/valops.c,v
retrieving revision 1.164
diff -u -p -r1.164 valops.c
--- gdb/valops.c 13 Jul 2006 04:31:42 -0000 1.164
+++ gdb/valops.c 25 Aug 2006 01:42:43 -0000
@@ -501,7 +501,8 @@ value_at (struct type *type, CORE_ADDR a
/* Return a lazy value with type TYPE located at ADDR (cf. value_at). */

struct value *
-value_at_lazy (struct type *type, CORE_ADDR addr)
+value_at_lazy_tls (struct type *type, CORE_ADDR addr,
+ struct objfile *tls_objfile)
{
struct value *val;

@@ -512,11 +513,19 @@ value_at_lazy (struct type *type, CORE_A

VALUE_LVAL (val) = lval_memory;
VALUE_ADDRESS (val) = addr;
+ if (tls_objfile != NULL)
+ set_value_tls_objfile (val, tls_objfile);
set_value_lazy (val, 1);

return val;
}

+struct value *
+value_at_lazy (struct type *type, CORE_ADDR addr)
+{
+ return value_at_lazy_tls (type, addr, NULL);
+}
+
/* Called only from the value_contents and value_contents_all()
macros, if the current data for a variable needs to be loaded into
value_contents(VAL). Fetches the data from the user's process, and
@@ -538,7 +547,17 @@ value_fetch_lazy (struct value *val)

struct type *type = value_type (val);
if (length)
- read_memory (addr, value_contents_all_raw (val), length);
+ {
+ struct objfile *tls_objfile = value_tls_objfile (val);
+
+ if (tls_objfile != NULL)
+ {
+ /* `target_translate_tls_address' uses `inferior_ptid'. */
+ addr = target_translate_tls_address (tls_objfile, addr);
+ }
+
+ read_memory (addr, value_contents_all_raw (val), length);
+ }

set_value_lazy (val, 0);
return 0;
@@ -596,6 +615,7 @@ value_assign (struct value *toval, struc
CORE_ADDR changed_addr;
int changed_len;
gdb_byte buffer[sizeof (LONGEST)];
+ struct objfile *tls_objfile = value_tls_objfile (toval);

if (value_bitsize (toval))
{
@@ -624,6 +644,13 @@ value_assign (struct value *toval, struc
dest_buffer = value_contents (fromval);
}

+ if (tls_objfile != NULL)
+ {
+ /* `target_translate_tls_address' uses `inferior_ptid'. */
+ changed_addr = target_translate_tls_address (tls_objfile,
+ changed_addr);
+ }
+
write_memory (changed_addr, dest_buffer, changed_len);
if (deprecated_memory_changed_hook)
deprecated_memory_changed_hook (changed_addr, changed_len);
Index: gdb/value.c
===================================================================
RCS file: /cvs/src/src/gdb/value.c,v
retrieving revision 1.36
diff -u -p -r1.36 value.c
--- gdb/value.c 31 Mar 2006 10:36:18 -0000 1.36
+++ gdb/value.c 25 Aug 2006 01:42:47 -0000
@@ -158,6 +158,9 @@ struct value
actually exist in the program. */
char optimized_out;

+ /* TLS owner. */
+ struct objfile *tls_objfile;
+
/* Actual contents of the value. For use of this value; setting it
uses the stuff above. Not valid if lazy is nonzero. Target
byte-order. We force it to be aligned properly for any possible
@@ -230,6 +233,7 @@ allocate_value (struct type *type)
VALUE_REGNUM (val) = -1;
val->lazy = 0;
val->optimized_out = 0;
+ val->tls_objfile = NULL;
val->embedded_offset = 0;
val->pointed_to_offset = 0;
val->modifiable = 1;
@@ -344,6 +348,18 @@ set_value_lazy (struct value *value, int
value->lazy = val;
}

+struct objfile *
+value_tls_objfile (struct value *value)
+{
+ return value->tls_objfile;
+}
+
+void
+set_value_tls_objfile (struct value *value, struct objfile *tls_objfile)
+{
+ value->tls_objfile = tls_objfile;
+}
+
const gdb_byte *
value_contents (struct value *value)
{
Index: gdb/value.h
===================================================================
RCS file: /cvs/src/src/gdb/value.h,v
retrieving revision 1.92
diff -u -p -r1.92 value.h
--- gdb/value.h 13 Jul 2006 04:31:42 -0000 1.92
+++ gdb/value.h 25 Aug 2006 01:42:48 -0000
@@ -154,6 +154,10 @@ extern void set_value_embedded_offset (s
extern int value_lazy (struct value *);
extern void set_value_lazy (struct value *value, int val);

+extern struct objfile *value_tls_objfile (struct value *value);
+extern void set_value_tls_objfile (struct value *value,
+ struct objfile *tls_objfile);
+
/* value_contents() and value_contents_raw() both return the address
of the gdb buffer used to hold a copy of the contents of the lval.
value_contents() is used when the contents of the buffer are needed
@@ -277,6 +281,8 @@ extern struct value *value_from_double (
extern struct value *value_from_string (char *string);

extern struct value *value_at (struct type *type, CORE_ADDR addr);
+extern struct value *value_at_lazy_tls (struct type *type, CORE_ADDR addr,
+ struct objfile *tls_objfile);
extern struct value *value_at_lazy (struct type *type, CORE_ADDR addr);

extern struct value *value_from_register (struct type *type, int regnum,
Index: gdb/testsuite/gdb.threads/tls-nodebug.c
===================================================================
RCS file: gdb/testsuite/gdb.threads/tls-nodebug.c
diff -N gdb/testsuite/gdb.threads/tls-nodebug.c
--- /dev/null 1 Jan 1970 00:00:00 -0000
+++ gdb/testsuite/gdb.threads/tls-nodebug.c 25 Aug 2006 01:42:52 -0000
@@ -0,0 +1,10 @@
+/* Test accessing TLS based variable without any debug info compiled. */
+
+#include <pthread.h>
+
+__thread int thread_local = 42;
+
+int main(void)
+{
+ return 0;
+}
Index: gdb/testsuite/gdb.threads/tls-nodebug.exp
===================================================================
RCS file: gdb/testsuite/gdb.threads/tls-nodebug.exp
diff -N gdb/testsuite/gdb.threads/tls-nodebug.exp
--- /dev/null 1 Jan 1970 00:00:00 -0000
+++ gdb/testsuite/gdb.threads/tls-nodebug.exp 25 Aug 2006 01:42:52 -0000
@@ -0,0 +1,52 @@
+# tls.exp -- Expect script to test thread-local storage without debuginfo
+# Copyright (C) 2006 Free Software Foundation, Inc.
+
+# 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 2 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
+
+# Please email any bugs, comments, and/or additions to this file to:
+# bug-gdb@prep.ai.mit.edu
+
+set testfile tls-nodebug
+set srcfile ${testfile}.c
+set binfile ${objdir}/${subdir}/${testfile}
+
+if [istarget "*-*-linux"] then {
+ set target_cflags "-D_MIT_POSIX_THREADS"
+} else {
+ set target_cflags ""
+}
+
+if {[gdb_compile_pthreads "${srcdir}/${subdir}/${srcfile}" "${binfile}" executable []] != "" } {
+ return -1
+}
+
+gdb_exit
+gdb_start
+gdb_reinitialize_dir $srcdir/$subdir
+
+gdb_load ${binfile}
+if ![runto_main] then {
+ fail "Can't run to main"
+ return 0
+}
+
+# Formerly: Cannot access memory at address 0x0
+gdb_test "p thread_local" "= 42" "thread local storage"
+
+# Done!
+#
+gdb_exit
+
+return 0