--- /dev/null
+https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=185337
+
+2008-02-24 Jan Kratochvil <jan.kratochvil@redhat.com>
+
+ Port to GDB-6.8pre.
+
+currently for trivial nonthreaded helloworld with no debug info up to -ggdb2 you
+will get:
+ (gdb) p errno
+ [some error]
+
+* with -ggdb2 and less "errno" in fact does not exist anywhere as it was
+ compiled to "(*__errno_location ())" and the macro definition is not present.
+ Unfortunately gdb will find the TLS symbol and it will try to access it but
+ as the program has been compiled without -lpthread the TLS base register
+ (%gs on i386) is not setup and it will result in:
+ Cannot access memory at address 0x8
+
+Attached suggestion patch how to deal with the most common "errno" symbol
+for the most common under-ggdb3 compiled programs.
+
+Original patch hooked into target_translate_tls_address. But its inferior
+call invalidates `struct frame *' in the callers - RH BZ 690908.
+
+
+2007-11-03 Jan Kratochvil <jan.kratochvil@redhat.com>
+
+ * ./gdb/dwarf2read.c (read_partial_die, dwarf2_linkage_name): Prefer
+ DW_AT_MIPS_linkage_name over DW_AT_name now only for non-C.
+
+glibc-debuginfo-2.7-2.x86_64: /usr/lib/debug/lib64/libc.so.6.debug:
+ <81a2> DW_AT_name : (indirect string, offset: 0x280e): __errno_location
+ <81a8> DW_AT_MIPS_linkage_name: (indirect string, offset: 0x2808): *__GI___errno_location
+
+--- a/gdb/printcmd.c
++++ b/gdb/printcmd.c
+@@ -967,6 +967,8 @@ print_command_1 (char *exp, int inspect, int voidprint)
+
+ if (exp && *exp)
+ {
++ if (strcmp (exp, "errno") == 0)
++ exp = "*((int *(*) (void)) __errno_location) ()";
+ expr = parse_expression (exp);
+ old_chain = make_cleanup (free_current_contents, &expr);
+ cleanup = 1;
+Index: gdb-7.2/gdb/testsuite/gdb.dwarf2/dw2-errno.c
+===================================================================
+--- /dev/null 1970-01-01 00:00:00.000000000 +0000
++++ gdb-7.2/gdb/testsuite/gdb.dwarf2/dw2-errno.c 2011-03-29 10:55:35.000000000 +0200
+@@ -0,0 +1,28 @@
++/* This testcase is part of GDB, the GNU debugger.
++
++ Copyright 2005, 2007 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 */
++
++#include <errno.h>
++
++int main()
++{
++ errno = 42;
++
++ return 0; /* breakpoint */
++}
+Index: gdb-7.2/gdb/testsuite/gdb.dwarf2/dw2-errno.exp
+===================================================================
+--- /dev/null 1970-01-01 00:00:00.000000000 +0000
++++ gdb-7.2/gdb/testsuite/gdb.dwarf2/dw2-errno.exp 2011-03-29 10:55:35.000000000 +0200
+@@ -0,0 +1,60 @@
++# Copyright 2007 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/>.
++
++set testfile dw2-errno
++set srcfile ${testfile}.c
++set binfile ${objdir}/${subdir}/${testfile}
++
++proc prep {} {
++ global srcdir subdir binfile
++ gdb_exit
++ gdb_start
++ gdb_reinitialize_dir $srcdir/$subdir
++ gdb_load ${binfile}
++
++ runto_main
++
++ gdb_breakpoint [gdb_get_line_number "breakpoint"]
++ gdb_continue_to_breakpoint "breakpoint"
++}
++
++if { [gdb_compile "${srcdir}/${subdir}/${srcfile}" "${binfile}" executable "additional_flags=-g2"] != "" } {
++ untested "Couldn't compile test program"
++ return -1
++}
++prep
++gdb_test "print errno" ".* = 42" "errno with macros=N threads=N"
++
++if { [gdb_compile "${srcdir}/${subdir}/${srcfile}" "${binfile}" executable "additional_flags=-g3"] != "" } {
++ untested "Couldn't compile test program"
++ return -1
++}
++prep
++gdb_test "print errno" ".* = 42" "errno with macros=Y threads=N"
++
++if {[gdb_compile_pthreads "${srcdir}/${subdir}/${srcfile}" "${binfile}" executable "additional_flags=-g2"] != "" } {
++ return -1
++}
++prep
++gdb_test "print errno" ".* = 42" "errno with macros=N threads=Y"
++
++if {[gdb_compile_pthreads "${srcdir}/${subdir}/${srcfile}" "${binfile}" executable "additional_flags=-g3"] != "" } {
++ return -1
++}
++prep
++gdb_test "print errno" ".* = 42" "errno with macros=Y threads=Y"
++
++# TODO: Test the error on resolving ERRNO with only libc loaded.
++# Just how to find the current libc filename?
projects / people / pmueller / ipfire-3.x.git / blobdiff