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[archer-jankratochvil-misc] Fix TLS access across files
- From: Jan Kratochvil <jan dot kratochvil at redhat dot com>
- To: archer at sourceware dot org
- Date: Mon, 1 Dec 2008 15:13:45 +0100
- Subject: [archer-jankratochvil-misc] Fix TLS access across files
You get a "Cannot access memory at address 0x4" when accessing TLS variable.
Testsuite addition, no regressions (x86_64-unknown-linux-gnu):
+PASS: gdb.threads/tls.exp: p a_thread_local
+PASS: gdb.threads/tls.exp: p file2_thread_local
+PASS: gdb.threads/tls.exp: info address file2_thread_local
+PASS: gdb.threads/tls.exp: p a_thread_local second time
+PASS: gdb.threads/tls.exp: info address a_thread_local
http://sourceware.org/ml/gdb/2008-07/msg00244.html
http://sourceware.org/ml/gdb/2008-07/msg00341.html
http://sourceware.org/ml/gdb-patches/2008-08/threads.html#00026
http://sourceware.org/ml/gdb-patches/2008-09/msg00204.html
http://sourceware.org/ml/gdb-patches/2008-11/threads.html#00706
2008-11-29 Jan Kratochvil <jan.kratochvil@redhat.com>
Fix resolving external references to TLS variables.
* findvar.c: Include `objfiles.h'.
(read_var_value <LOC_UNRESOLVED>): New variable `obj_section'. Handle
SEC_THREAD_LOCAL variables.
* printcmd.c (address_info <LOC_UNRESOLVED>): New variable
`obj_section'. Handle SEC_THREAD_LOCAL variables.
2008-11-29 Jan Kratochvil <jan.kratochvil@redhat.com>
Test resolving external references to TLS variables.
* gdb.threads/tls.exp: New tests to examine A_THREAD_LOCAL and
FILE2_THREAD_LOCAL.
(testfile2, srcfile2): New variables.
* gdb.threads/tls.c (file2_thread_local)
(function_referencing_file2_thread_local): New.
* gdb.threads/tls2.c: New file.
---
gdb/findvar.c | 8 ++++++++
gdb/printcmd.c | 14 +++++++++++++-
gdb/testsuite/gdb.threads/tls.c | 9 +++++++++
gdb/testsuite/gdb.threads/tls.exp | 18 +++++++++++++++++-
gdb/testsuite/gdb.threads/tls2.c | 28 ++++++++++++++++++++++++++++
5 files changed, 75 insertions(+), 2 deletions(-)
create mode 100644 gdb/testsuite/gdb.threads/tls2.c
diff --git a/gdb/findvar.c b/gdb/findvar.c
index 4796721..d753a35 100644
--- a/gdb/findvar.c
+++ b/gdb/findvar.c
@@ -34,6 +34,7 @@
#include "regcache.h"
#include "user-regs.h"
#include "block.h"
+#include "objfiles.h"
/* Basic byte-swapping routines. GDB has needed these for a long time...
All extract a target-format integer at ADDR which is LEN bytes long. */
@@ -536,6 +537,7 @@ read_var_value (struct symbol *var, struct frame_info *frame)
case LOC_UNRESOLVED:
{
struct minimal_symbol *msym;
+ struct obj_section *obj_section;
msym = lookup_minimal_symbol (SYMBOL_LINKAGE_NAME (var), NULL, NULL);
if (msym == NULL)
@@ -545,6 +547,12 @@ read_var_value (struct symbol *var, struct frame_info *frame)
SYMBOL_OBJ_SECTION (msym));
else
addr = SYMBOL_VALUE_ADDRESS (msym);
+
+ /* SYMBOL_VALUE_ADDRESS should return the translated address. */
+ obj_section = SYMBOL_OBJ_SECTION (msym);
+ if (obj_section
+ && (obj_section->the_bfd_section->flags & SEC_THREAD_LOCAL) != 0)
+ addr = target_translate_tls_address (obj_section->objfile, addr);
}
break;
diff --git a/gdb/printcmd.c b/gdb/printcmd.c
index 81638fb..03955ce 100644
--- a/gdb/printcmd.c
+++ b/gdb/printcmd.c
@@ -1234,6 +1234,7 @@ address_info (char *exp, int from_tty)
case LOC_UNRESOLVED:
{
struct minimal_symbol *msym;
+ struct obj_section *obj_section;
msym = lookup_minimal_symbol (SYMBOL_LINKAGE_NAME (sym), NULL, NULL);
if (msym == NULL)
@@ -1241,8 +1242,19 @@ address_info (char *exp, int from_tty)
else
{
section = SYMBOL_OBJ_SECTION (msym);
- printf_filtered (_("static storage at address "));
load_addr = SYMBOL_VALUE_ADDRESS (msym);
+
+ /* SYMBOL_VALUE_ADDRESS should return the translated address. */
+ if (section
+ && (section->the_bfd_section->flags & SEC_THREAD_LOCAL) != 0)
+ {
+ printf_filtered (_("a thread-local variable at offset %s "
+ "at final address "), paddr_nz (load_addr));
+ load_addr = target_translate_tls_address (section->objfile,
+ load_addr);
+ }
+ else
+ printf_filtered (_("static storage at address "));
fputs_filtered (paddress (load_addr), gdb_stdout);
if (section_is_overlay (section))
{
diff --git a/gdb/testsuite/gdb.threads/tls.c b/gdb/testsuite/gdb.threads/tls.c
index 9b2145e..8f2443c 100644
--- a/gdb/testsuite/gdb.threads/tls.c
+++ b/gdb/testsuite/gdb.threads/tls.c
@@ -20,6 +20,9 @@
__thread int a_thread_local;
__thread int another_thread_local;
+/* psymtabs->symtabs resolving check. */
+extern __thread int file2_thread_local;
+
/* Global variable just for info addr in gdb. */
int a_global;
@@ -119,6 +122,12 @@ void *spin( vp )
}
void
+function_referencing_file2_thread_local (void)
+{
+ file2_thread_local = file2_thread_local;
+}
+
+void
do_pass()
{
int i;
diff --git a/gdb/testsuite/gdb.threads/tls.exp b/gdb/testsuite/gdb.threads/tls.exp
index 614c06e..770baf0 100644
--- a/gdb/testsuite/gdb.threads/tls.exp
+++ b/gdb/testsuite/gdb.threads/tls.exp
@@ -15,7 +15,9 @@
# along with this program. If not, see <http://www.gnu.org/licenses/>. */
set testfile tls
+set testfile2 tls2
set srcfile ${testfile}.c
+set srcfile2 ${testfile2}.c
set binfile ${objdir}/${subdir}/${testfile}
if [istarget "*-*-linux"] then {
@@ -24,7 +26,7 @@ if [istarget "*-*-linux"] then {
set target_cflags ""
}
-if {[gdb_compile_pthreads "${srcdir}/${subdir}/${srcfile}" "${binfile}" executable [list debug "incdir=${objdir}"]] != "" } {
+if {[gdb_compile_pthreads "${srcdir}/${subdir}/${srcfile} ${srcdir}/${subdir}/${srcfile2}" "${binfile}" executable [list debug "incdir=${objdir}"]] != "" } {
return -1
}
@@ -284,6 +286,20 @@ gdb_test "info address a_global" \
setup_kfail "gdb/1294" "*-*-*"
gdb_test "info address me" ".*me.*is a variable at offset.*" "info address me"
+
+# Test LOC_UNRESOLVED references resolving for `extern' TLS variables.
+
+gdb_test "p a_thread_local" " = \[0-9\]+"
+# Here it could crash with: Cannot access memory at address 0x0
+gdb_test "p file2_thread_local" " = \[0-9\]+"
+# Depending on the current lookup scope we may get two answers:
+# LOC_UNRESOLVED: Symbol "file2_thread_local" is a thread-local variable at offset 8 at final address 0x7ffff7fdb94c.
+# LOC_COMPUTED: Symbol "file2_thread_local" is a thread-local variable at offset 8 in the thread-local storage for `.../gdb.threads/tls'.
+gdb_test "info address file2_thread_local" "Symbol \"file2_thread_local\" is a thread-local variable.*"
+# Here it could also crash with: Cannot access memory at address 0x0
+gdb_test "p a_thread_local" " = \[0-9\]+" "p a_thread_local second time"
+gdb_test "info address a_thread_local" "Symbol \"a_thread_local\" is a thread-local variable.*"
+
# Done!
#
gdb_exit
diff --git a/gdb/testsuite/gdb.threads/tls2.c b/gdb/testsuite/gdb.threads/tls2.c
new file mode 100644
index 0000000..f87ec2f
--- /dev/null
+++ b/gdb/testsuite/gdb.threads/tls2.c
@@ -0,0 +1,28 @@
+/* This testcase is part of GDB, the GNU debugger.
+
+ Copyright 2008 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 3 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, see <http://www.gnu.org/licenses/>.
+
+ Please email any bugs, comments, and/or additions to this file to:
+ bug-gdb@prep.ai.mit.edu */
+
+extern __thread int a_thread_local;
+__thread int file2_thread_local;
+
+void
+function_referencing_a_thread_local (void)
+{
+ a_thread_local = a_thread_local;
+}
--
1.6.0.4