This is the mail archive of the
gdb-patches@sourceware.org
mailing list for the GDB project.
[patch] Support constant DW_AT_data_member_location by GCC PR debug/40659
- From: Jan Kratochvil <jan dot kratochvil at redhat dot com>
- To: gdb-patches at sourceware dot org
- Date: Tue, 11 Aug 2009 21:53:00 +0200
- Subject: [patch] Support constant DW_AT_data_member_location by GCC PR debug/40659
Hi,
GDB can now segfault on a GCC-4.5-HEAD output due to the simplification:
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40659
<2><3b>: Abbrev Number: 2 (DW_TAG_inheritance)
<3c> DW_AT_type : <0x27>
<40> DW_AT_data_member_location: 2 byte block: 23 0 (DW_OP_plus_uconst: 0)
->
<40> DW_AT_data_member_location: 0
DW_AT_data_member_location DW_FORM_data1
Important part is the dwarf2_add_field change of /* C++ base class field. */,
other changes are only a cleanup.
Regression tested on {x86_64,x86_64-m32,i686}-fedora11-linux-gnu.
Thanks,
Jan
gdb/
2009-08-11 Jan Kratochvil <jan.kratochvil@redhat.com>
Support constant DW_AT_data_member_location by GCC PR debug/40659.
* dwarf2read.c (dwarf2_get_attr_constant_value): Prototype now uses
CORE_ADDR.
(dwarf2_add_field, dwarf2_add_member_fn, read_common_block): Use
dwarf2_get_attr_constant_value.
(read_subrange_type, read_subrange_type): Add new parameter to the
dwarf2_get_attr_constant_value call.
(dwarf2_get_ref_die_offset): Fix the return value comment. Change the
function data type INT to CORE_ADDR. Support also attr_form_is_block.
gdb/testsuite/
2009-08-11 Jan Kratochvil <jan.kratochvil@redhat.com>
Support constant DW_AT_data_member_location by GCC PR debug/40659.
* gdb.dwarf2/dw2-inheritance.exp, gdb.dwarf2/dw2-inheritance.S: New.
--- a/gdb/dwarf2read.c
+++ b/gdb/dwarf2read.c
@@ -1078,7 +1078,8 @@ static int is_ref_attr (struct attribute *);
static unsigned int dwarf2_get_ref_die_offset (struct attribute *);
-static int dwarf2_get_attr_constant_value (struct attribute *, int);
+static CORE_ADDR dwarf2_get_attr_constant_value (struct attribute *, CORE_ADDR,
+ struct dwarf2_cu *);
static struct die_info *follow_die_ref_or_sig (struct die_info *,
struct attribute *,
@@ -4384,21 +4385,8 @@ dwarf2_add_field (struct field_info *fip, struct die_info *die,
/* Get bit offset of field. */
attr = dwarf2_attr (die, DW_AT_data_member_location, cu);
if (attr)
- {
- int byte_offset;
-
- if (attr_form_is_section_offset (attr))
- {
- dwarf2_complex_location_expr_complaint ();
- byte_offset = 0;
- }
- else if (attr_form_is_constant (attr))
- byte_offset = dwarf2_get_attr_constant_value (attr, 0);
- else
- byte_offset = decode_locdesc (DW_BLOCK (attr), cu);
-
- SET_FIELD_BITPOS (*fp, byte_offset * bits_per_byte);
- }
+ SET_FIELD_BITPOS (*fp, dwarf2_get_attr_constant_value (attr, 0, cu)
+ * bits_per_byte);
attr = dwarf2_attr (die, DW_AT_bit_offset, cu);
if (attr)
{
@@ -4490,7 +4478,7 @@ dwarf2_add_field (struct field_info *fip, struct die_info *die,
/* C++ base class field. */
attr = dwarf2_attr (die, DW_AT_data_member_location, cu);
if (attr)
- SET_FIELD_BITPOS (*fp, decode_locdesc (DW_BLOCK (attr), cu)
+ SET_FIELD_BITPOS (*fp, dwarf2_get_attr_constant_value (attr, 0, cu)
* bits_per_byte);
FIELD_BITSIZE (*fp) = 0;
FIELD_TYPE (*fp) = die_type (die, cu);
@@ -4709,22 +4697,7 @@ dwarf2_add_member_fn (struct field_info *fip, struct die_info *die,
/* Get index in virtual function table if it is a virtual member function. */
attr = dwarf2_attr (die, DW_AT_vtable_elem_location, cu);
if (attr)
- {
- /* Support the .debug_loc offsets */
- if (attr_form_is_block (attr))
- {
- fnp->voffset = decode_locdesc (DW_BLOCK (attr), cu) + 2;
- }
- else if (attr_form_is_section_offset (attr))
- {
- dwarf2_complex_location_expr_complaint ();
- }
- else
- {
- dwarf2_invalid_attrib_class_complaint ("DW_AT_vtable_elem_location",
- fieldname);
- }
- }
+ fnp->voffset = dwarf2_get_attr_constant_value (attr, -2, cu) + 2;
}
/* Create the vector of member function fields, and attach it to the type. */
@@ -5413,22 +5386,7 @@ read_common_block (struct die_info *die, struct dwarf2_cu *cu)
attr = dwarf2_attr (die, DW_AT_location, cu);
if (attr)
- {
- /* Support the .debug_loc offsets */
- if (attr_form_is_block (attr))
- {
- base = decode_locdesc (DW_BLOCK (attr), cu);
- }
- else if (attr_form_is_section_offset (attr))
- {
- dwarf2_complex_location_expr_complaint ();
- }
- else
- {
- dwarf2_invalid_attrib_class_complaint ("DW_AT_location",
- "common block member");
- }
- }
+ base = dwarf2_get_attr_constant_value (attr, 0, cu);
if (die->child != NULL)
{
child_die = die->child;
@@ -5439,7 +5397,7 @@ read_common_block (struct die_info *die, struct dwarf2_cu *cu)
if (attr)
{
SYMBOL_VALUE_ADDRESS (sym) =
- base + decode_locdesc (DW_BLOCK (attr), cu);
+ base + dwarf2_get_attr_constant_value (attr, 0, cu);
add_symbol_to_list (sym, &global_symbols);
}
child_die = sibling_die (child_die);
@@ -5955,7 +5913,7 @@ read_subrange_type (struct die_info *die, struct dwarf2_cu *cu)
but we don't know how to handle it. */
attr = dwarf2_attr (die, DW_AT_lower_bound, cu);
if (attr)
- low = dwarf2_get_attr_constant_value (attr, 0);
+ low = dwarf2_get_attr_constant_value (attr, 0, cu);
attr = dwarf2_attr (die, DW_AT_upper_bound, cu);
if (attr)
@@ -5976,7 +5934,7 @@ read_subrange_type (struct die_info *die, struct dwarf2_cu *cu)
high = low - 1;
}
else
- high = dwarf2_get_attr_constant_value (attr, 1);
+ high = dwarf2_get_attr_constant_value (attr, 1, cu);
}
range_type = create_range_type (NULL, base_type, low, high);
@@ -10181,11 +10139,12 @@ dwarf2_get_ref_die_offset (struct attribute *attr)
return 0;
}
-/* Return the constant value held by the given attribute. Return -1
+/* Return the constant value held by the given attribute. Return DEFAULT_VALUE
if the value held by the attribute is not constant. */
-static int
-dwarf2_get_attr_constant_value (struct attribute *attr, int default_value)
+static CORE_ADDR
+dwarf2_get_attr_constant_value (struct attribute *attr, CORE_ADDR default_value,
+ struct dwarf2_cu *cu)
{
if (attr->form == DW_FORM_sdata)
return DW_SND (attr);
@@ -10195,6 +10154,8 @@ dwarf2_get_attr_constant_value (struct attribute *attr, int default_value)
|| attr->form == DW_FORM_data4
|| attr->form == DW_FORM_data8)
return DW_UNSND (attr);
+ else if (attr_form_is_block (attr))
+ return decode_locdesc (DW_BLOCK (attr), cu);
else
{
complaint (&symfile_complaints, _("Attribute value is not a constant (%s)"),
--- /dev/null
+++ b/gdb/testsuite/gdb.dwarf2/dw2-inheritance.S
@@ -0,0 +1,98 @@
+/* This testcase is part of GDB, the GNU debugger.
+
+ Copyright 2009 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/>. */
+
+/* Test DW_TAG_inheritance using constant DW_AT_data_member_location
+ introduced by GCC PR debug/40659. */
+
+/* Debug information */
+
+ .section .debug_info
+.Lcu1_begin:
+ /* CU header */
+ .4byte .Lcu1_end - .Lcu1_start /* Length of Compilation Unit */
+.Lcu1_start:
+ .2byte 2 /* DWARF Version */
+ .4byte .Labbrev1_begin /* Offset into abbrev section */
+ .byte 4 /* Pointer size */
+
+ /* CU die */
+ .uleb128 1 /* Abbrev: DW_TAG_compile_unit */
+ .4byte .Lline1_begin /* DW_AT_stmt_list */
+ .ascii "file1.txt\0" /* DW_AT_name */
+ .ascii "GNU C 3.3.3\0" /* DW_AT_producer */
+ .byte 4 /* DW_LANG_C_plus_plus (C++) */
+
+.Lbase:
+ .uleb128 3 /* Abbrev: DW_TAG_class_type */
+ .ascii "base\0" /* DW_AT_name */
+ .byte 4 /* DW_AT_byte_size */
+
+ .byte 0 /* End of children of "base" */
+
+ .uleb128 3 /* Abbrev: DW_TAG_class_type */
+ .ascii "inherited\0" /* DW_AT_name */
+ .byte 8 /* DW_AT_byte_size */
+
+ .uleb128 2 /* Abbrev: DW_TAG_inheritance */
+ .4byte .Lbase-.Lcu1_begin /* DW_AT_type */
+ .byte 0 /* DW_AT_data_member_location */
+
+ .byte 0 /* End of children of "inherited" */
+
+ .byte 0 /* End of children of CU */
+
+.Lcu1_end:
+
+/* Abbrev table */
+ .section .debug_abbrev
+.Labbrev1_begin:
+ .uleb128 1 /* Abbrev code */
+ .uleb128 0x11 /* DW_TAG_compile_unit */
+ .byte 1 /* has_children */
+ .uleb128 0x10 /* DW_AT_stmt_list */
+ .uleb128 0x6 /* DW_FORM_data4 */
+ .uleb128 0x3 /* DW_AT_name */
+ .uleb128 0x8 /* DW_FORM_string */
+ .uleb128 0x25 /* DW_AT_producer */
+ .uleb128 0x8 /* DW_FORM_string */
+ .uleb128 0x13 /* DW_AT_language */
+ .uleb128 0xb /* DW_FORM_data1 */
+ .byte 0x0 /* Terminator */
+ .byte 0x0 /* Terminator */
+
+ .uleb128 2 /* Abbrev code */
+ .uleb128 0x1c /* DW_TAG_inheritance */
+ .byte 0 /* has_children */
+ .uleb128 0x49 /* DW_AT_type */
+ .uleb128 0x13 /* DW_FORM_ref4 */
+ .uleb128 0x38 /* DW_AT_data_member_location */
+ .uleb128 0xb /* DW_FORM_data1 */
+ .byte 0x0 /* Terminator */
+ .byte 0x0 /* Terminator */
+
+ .uleb128 3 /* Abbrev code */
+ .uleb128 0x02 /* DW_TAG_class_type */
+ .byte 1 /* has_children */
+ .uleb128 0x3 /* DW_AT_name */
+ .uleb128 0x8 /* DW_FORM_string */
+ .uleb128 0xb /* DW_AT_byte_size */
+ .uleb128 0xb /* DW_FORM_data1 */
+ .byte 0x0 /* Terminator */
+ .byte 0x0 /* Terminator */
+
+ .byte 0x0 /* Terminator */
+ .byte 0x0 /* Terminator */
--- /dev/null
+++ b/gdb/testsuite/gdb.dwarf2/dw2-inheritance.exp
@@ -0,0 +1,40 @@
+# Copyright 2009 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/>.
+
+# Test DW_TAG_inheritance using constant DW_AT_data_member_location
+# introduced by GCC PR debug/40659.
+
+# This test can only be run on targets which support DWARF-2 and use gas.
+# For now pick a sampling of likely targets.
+if {![istarget *-*-linux*]
+ && ![istarget *-*-gnu*]
+ && ![istarget *-*-elf*]
+ && ![istarget *-*-openbsd*]
+ && ![istarget arm-*-eabi*]
+ && ![istarget powerpc-*-eabi*]} {
+ return 0
+}
+
+set testfile "dw2-inheritance"
+set srcfile ${testfile}.S
+set executable ${testfile}.x
+
+if { [gdb_compile "${srcdir}/${subdir}/${srcfile}" "${objdir}/${subdir}/${executable}" object {nodebug}] != "" } {
+ return -1
+}
+
+clean_restart $executable
+
+gdb_test "ptype inherited" "type = class inherited .*"