gdb returns an incorrect back trace when applying a debuginfo
https://bugzilla.redhat.com/show_bug.cgi?id=1339862
Index: gdb-7.9.90.20150709/gdb/solib-svr4.c
===================================================================
--- gdb-7.9.90.20150709.orig/gdb/solib-svr4.c 2015-07-09 18:18:54.526417766 +0200
+++ gdb-7.9.90.20150709/gdb/solib-svr4.c 2015-07-09 18:19:33.074746586 +0200
@@ -1381,14 +1381,27 @@ svr4_read_so_list (CORE_ADDR lm, CORE_AD
}
{
- struct bfd_build_id *build_id;
+ struct bfd_build_id *build_id = NULL;
strncpy (newobj->so_original_name, buffer, SO_NAME_MAX_PATH_SIZE - 1);
newobj->so_original_name[SO_NAME_MAX_PATH_SIZE - 1] = '\0';
/* May get overwritten below. */
strcpy (newobj->so_name, newobj->so_original_name);
- build_id = build_id_addr_get (newobj->lm_info->l_ld);
+ /* In the case the main executable was found according to its build-id
+ (from a core file) prevent loading a different build of a library
+ with accidentally the same SO_NAME.
+
+ It suppresses bogus backtraces (and prints "??" there instead) if
+ the on-disk files no longer match the running program version.
+
+ If the main executable was not loaded according to its build-id do
+ not do any build-id checking of the libraries. There may be missing
+ build-ids dumped in the core file and we would map all the libraries
+ to the only existing file loaded that time - the executable. */
+ if (symfile_objfile != NULL
+ && (symfile_objfile->flags & OBJF_BUILD_ID_CORE_LOADED) != 0)
+ build_id = build_id_addr_get (newobj->lm_info->l_ld);
if (build_id != NULL)
{
char *name, *build_id_filename;
@@ -1403,23 +1416,7 @@ svr4_read_so_list (CORE_ADDR lm, CORE_AD
xfree (name);
}
else
- {
- debug_print_missing (newobj->so_name, build_id_filename);
-
- /* In the case the main executable was found according to
- its build-id (from a core file) prevent loading
- a different build of a library with accidentally the
- same SO_NAME.
-
- It suppresses bogus backtraces (and prints "??" there
- instead) if the on-disk files no longer match the
- running program version. */
-
- if (symfile_objfile != NULL
- && (symfile_objfile->flags
- & OBJF_BUILD_ID_CORE_LOADED) != 0)
- newobj->so_name[0] = 0;
- }
+ debug_print_missing (newobj->so_name, build_id_filename);
xfree (build_id_filename);
xfree (build_id);
--- /dev/null 2016-07-02 20:29:01.679404943 +0200
+++ gdb-7.11.50.20160721/gdb/testsuite/gdb.base/gcore-buildid-exec-but-not-solib.exp 2016-07-31 23:04:49.062753722 +0200
@@ -0,0 +1,105 @@
+# Copyright 2016 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/>.
+
+if {[skip_shlib_tests]} {
+ return 0
+}
+
+set testfile "gcore-buildid-exec-but-not-solib"
+set srcmainfile ${testfile}-main.c
+set srclibfile ${testfile}-lib.c
+set libfile [standard_output_file ${testfile}-lib.so]
+set objfile [standard_output_file ${testfile}-main.o]
+set executable ${testfile}-main
+set binfile [standard_output_file ${executable}]
+set gcorefile [standard_output_file ${executable}.gcore]
+set outdir [file dirname $binfile]
+
+if { [gdb_compile_shlib ${srcdir}/${subdir}/${srclibfile} ${libfile} "debug additional_flags=-Wl,--build-id"] != ""
+ || [gdb_compile ${srcdir}/${subdir}/${srcmainfile} ${objfile} object {debug}] != "" } {
+ unsupported "-Wl,--build-id compilation failed"
+ return -1
+}
+set opts [list debug shlib=${libfile} "additional_flags=-Wl,--build-id"]
+if { [gdb_compile ${objfile} ${binfile} executable $opts] != "" } {
+ unsupported "-Wl,--build-id compilation failed"
+ return -1
+}
+
+clean_restart $executable
+gdb_load_shlib $libfile
+
+# Does this gdb support gcore?
+set test "help gcore"
+gdb_test_multiple $test $test {
+ -re "Undefined command: .gcore.*\r\n$gdb_prompt $" {
+ # gcore command not supported -- nothing to test here.
+ unsupported "gdb does not support gcore on this target"
+ return -1;
+ }
+ -re "Save a core file .*\r\n$gdb_prompt $" {
+ pass $test
+ }
+}
+
+if { ![runto lib] } then {
+ return -1
+}
+
+set escapedfilename [string_to_regexp ${gcorefile}]
+
+set test "save a corefile"
+gdb_test_multiple "gcore ${gcorefile}" $test {
+ -re "Saved corefile ${escapedfilename}\r\n$gdb_prompt $" {
+ pass $test
+ }
+ -re "Can't create a corefile\r\n$gdb_prompt $" {
+ unsupported $test
+ return -1
+ }
+}
+
+# Now restart gdb and load the corefile.
+
+clean_restart $executable
+gdb_load_shlib $libfile
+
+set buildid [build_id_debug_filename_get $libfile]
+
+regsub {\.debug$} $buildid {} buildid
+
+set debugdir [standard_output_file ${testfile}-debugdir]
+file delete -force -- $debugdir
+
+file mkdir $debugdir/[file dirname $libfile]
+file copy $libfile $debugdir/${libfile}
+
+file mkdir $debugdir/[file dirname $buildid]
+file copy $libfile $debugdir/${buildid}
+
+remote_exec build "ln -s /lib ${debugdir}/"
+remote_exec build "ln -s /lib64 ${debugdir}/"
+# /usr is not needed, all the libs are in /lib64: libm.so.6 libc.so.6 ld-linux-x86-64.so.2
+
+gdb_test "set solib-absolute-prefix $debugdir"
+
+gdb_test_no_output "set debug-file-directory $debugdir" "set debug-file-directory"
+
+gdb_test "core ${gcorefile}" "Core was generated by .*" "re-load generated corefile"
+
+gdb_test "frame" "#0 \[^\r\n\]* lib .*" "library got loaded"
+
+gdb_test "bt"
+gdb_test "info shared"
--- /dev/null 2016-07-02 20:29:01.679404943 +0200
+++ gdb-7.11.50.20160721/gdb/testsuite/gdb.base/gcore-buildid-exec-but-not-solib-main.c 2016-07-28 21:06:40.977786922 +0200
@@ -0,0 +1,25 @@
+/* Copyright 2010 Free Software Foundation, Inc.
+
+ This file is part of GDB.
+
+ 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/>. */
+
+extern void lib (void);
+
+int
+main (void)
+{
+ lib ();
+ return 0;
+}
--- /dev/null 2016-07-02 20:29:01.679404943 +0200
+++ gdb-7.11.50.20160721/gdb/testsuite/gdb.base/gcore-buildid-exec-but-not-solib-lib.c 2016-07-28 21:06:40.977786922 +0200
@@ -0,0 +1,21 @@
+/* Copyright 2010 Free Software Foundation, Inc.
+
+ This file is part of GDB.
+
+ 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/>. */
+
+void
+lib (void)
+{
+}