[patch] Fix crash on DWARF C++ forward reference

[patch] Fix crash on DWARF C++ forward reference

[Jan Kratochvil]

Hi,

the problem is based on the testcase contained in GCC PR debug/28767
by Daniel J. with specially crafted forward-reference resulting in
a double-entry to quirk_gcc_member_function_pointer for the same DIE which
crashes GDB.  Problem has been seen in practice.

I understand the solution is not nice but I hope the DWARF reading functions
do not access much the content of referenced TYPEs.

No regressions on {x86_64,x86_64-m32}-fedora12-linux-gnu.


Thanks,
Jan


gdb/
2010-01-22  Jan Kratochvil  <jan.kratochvil@redhat.com>

	* dwarf2read.c (quirk_gcc_member_function_pointer): New variables type2,
	main_type_local, instance_flags_local and length_local.  Provide
	temporary memory for TYPE.  Exchange the TYPE and TYPE2 content.

gdb/testsuite/
2010-01-22  Jan Kratochvil  <jan.kratochvil@redhat.com>

	* gdb.dwarf2/member-ptr-forwardref.exp,
	gdb.dwarf2/member-ptr-forwardref.S: New.

--- a/gdb/dwarf2read.c
+++ b/gdb/dwarf2read.c
@@ -4903,7 +4903,10 @@ static struct type *
 quirk_gcc_member_function_pointer (struct die_info *die, struct dwarf2_cu *cu)
 {
   struct objfile *objfile = cu->objfile;
-  struct type *type;
+  struct type *type, *type2;
+  struct main_type main_type_local;
+  int instance_flags_local;
+  unsigned length_local;
   struct die_info *pfn_die, *delta_die;
   struct attribute *pfn_name, *delta_name;
   struct type *pfn_type, *domain_type;
@@ -4934,6 +4937,11 @@ quirk_gcc_member_function_pointer (struct die_info *die, struct dwarf2_cu *cu)
       || strcmp ("__delta", DW_STRING (delta_name)) != 0)
     return NULL;
 
+  /* Provide TYPE as a dummy memory for referencing from DIE during the
+     die_type call as we can deadlock otherwise.  */
+  type = alloc_type (objfile);
+  set_die_type (die, type, cu);
+
   /* Find the type of the method.  */
   pfn_type = die_type (pfn_die, cu);
   if (pfn_type == NULL
@@ -4948,12 +4956,28 @@ quirk_gcc_member_function_pointer (struct die_info *die, struct dwarf2_cu *cu)
     return NULL;
 
   domain_type = TYPE_TARGET_TYPE (TYPE_FIELD_TYPE (pfn_type, 0));
-  type = alloc_type (objfile);
   smash_to_method_type (type, domain_type, TYPE_TARGET_TYPE (pfn_type),
 			TYPE_FIELDS (pfn_type), TYPE_NFIELDS (pfn_type),
 			TYPE_VARARGS (pfn_type));
-  type = lookup_methodptr_type (type);
-  return set_die_type (die, type, cu);
+  type2 = lookup_methodptr_type (type);
+
+  /* Exchange TYPE and TYPE2 memory content as there may exist now references
+     to the dummy memory TYPE but they are meant to point to
+     TYPE_CODE_METHODPTR (and not TYPE_CODE_METHOD as they do right now).  */
+
+  main_type_local = *TYPE_MAIN_TYPE (type);
+  *TYPE_MAIN_TYPE (type) = *TYPE_MAIN_TYPE (type2);
+  *TYPE_MAIN_TYPE (type2) = main_type_local;
+  instance_flags_local = TYPE_INSTANCE_FLAGS (type);
+  TYPE_INSTANCE_FLAGS (type) = TYPE_INSTANCE_FLAGS (type2);
+  TYPE_INSTANCE_FLAGS (type2) = instance_flags_local;
+  length_local = TYPE_LENGTH (type);
+  TYPE_LENGTH (type) = TYPE_LENGTH (type2);
+  TYPE_LENGTH (type2) = length_local;
+
+  TYPE_TARGET_TYPE (type) = type2;
+  
+  return type;
 }
 
 /* Called when we find the DIE that starts a structure or union scope
--- /dev/null
+++ b/gdb/testsuite/gdb.dwarf2/member-ptr-forwardref.S
@@ -0,0 +1,327 @@
+/* This testcase is part of GDB, the GNU debugger.
+
+   Copyright 2010 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/>.  */
+
+/* The goal of this test is to provide anonymous DW_TAG_structure_type
+   containing __pfn + __delta (read in by quirk_gcc_member_function_pointer)
+   before DW_TAG_structure_type of "class C" to exploit the forward reference
+   through "__pfn" and back from DW_TAG_member "fp" of "class C".  As the
+   compiler may place the DIEs in arbitrary order they are rather prepared as
+   a .S file.
+
+   class C;
+   typedef int (C::*fp_t) ();
+   fp_t fp;
+   class C
+     {
+       int (C::*fp) ();
+     } c;  */
+
+	.file	"member-ptr-forwardref.cc"
+	.section	.debug_abbrev,"",@progbits
+.Ldebug_abbrev0:
+	.section	.debug_info,"",@progbits
+.Ldebug_info0:
+	.section	.debug_line,"",@progbits
+.Ldebug_line0:
+	.text
+.Ltext0:
+.globl fp
+	.bss
+	.align 4
+	.type	fp, @object
+	.size	fp, 8
+fp:
+	.zero	8
+.globl c
+	.align 4
+	.type	c, @object
+	.size	c, 8
+c:
+	.zero	8
+	.text
+.Letext0:
+	.file 1 "gdb.dwarf2/member-ptr-forwardref.cc"
+	.section	.debug_info
+	.long	0xa9	# Length of Compilation Unit Info
+	.value	0x3	# DWARF version number
+	.long	.Ldebug_abbrev0	# Offset Into Abbrev. Section
+	.byte	0x4	# Pointer Size (in bytes)
+	.uleb128 0x1	# (DIE (0xb) DW_TAG_compile_unit)
+	.long	.LASF2	# DW_AT_producer: "GNU C++ 4.4.2 20091222 (Red Hat 4.4.2-20)"
+	.byte	0x4	# DW_AT_language
+	.long	.LASF3	# DW_AT_name: "gdb.dwarf2/member-ptr-forwardref.cc"
+	.long	.LASF4	# DW_AT_comp_dir: "gdb/testsuite"
+	.long	.Ltext0	# DW_AT_low_pc
+	.long	.Letext0	# DW_AT_high_pc
+	.long	.Ldebug_line0	# DW_AT_stmt_list
+	.uleb128 0x2	# (DIE (0x25) DW_TAG_typedef)
+	.long	.LASF5	# DW_AT_name: "fp_t"
+	.byte	0x1	# DW_AT_decl_file (gdb.dwarf2/member-ptr-forwardref.cc)
+	.byte	0x13	# DW_AT_decl_line
+	.long	0x30	# DW_AT_type
+	.uleb128 0x3	# (DIE (0x30) DW_TAG_structure_type)
+	.byte	0x8	# DW_AT_byte_size
+	.byte	0x1	# DW_AT_decl_file (gdb.dwarf2/member-ptr-forwardref.cc)
+	.byte	0x13	# DW_AT_decl_line
+	.long	0x51	# DW_AT_sibling
+	.uleb128 0x4	# (DIE (0x38) DW_TAG_member)
+	.long	.LASF0	# DW_AT_name: "__pfn"
+	.byte	0x1	# DW_AT_decl_file (gdb.dwarf2/member-ptr-forwardref.cc)
+	.byte	0x13	# DW_AT_decl_line
+	.long	0x85	# DW_AT_type
+	.sleb128 0	# DW_AT_data_member_location
+	.uleb128 0x4	# (DIE (0x44) DW_TAG_member)
+	.long	.LASF1	# DW_AT_name: "__delta"
+	.byte	0x1	# DW_AT_decl_file (gdb.dwarf2/member-ptr-forwardref.cc)
+	.byte	0x13	# DW_AT_decl_line
+	.long	0x61	# DW_AT_type
+	.sleb128 4	# DW_AT_data_member_location
+	.byte	0x0	# end of children of DIE 0x30
+	.uleb128 0x5	# (DIE (0x51) DW_TAG_subroutine_type)
+	.long	0x61	# DW_AT_type
+	.long	0x61	# DW_AT_sibling
+	.uleb128 0x6	# (DIE (0x5a) DW_TAG_formal_parameter)
+	.long	0x68	# DW_AT_type
+	.byte	0x1	# DW_AT_artificial
+	.byte	0x0	# end of children of DIE 0x51
+	.uleb128 0x7	# (DIE (0x61) DW_TAG_base_type)
+	.byte	0x4	# DW_AT_byte_size
+	.byte	0x5	# DW_AT_encoding
+	.ascii "int\0"	# DW_AT_name
+	.uleb128 0x8	# (DIE (0x68) DW_TAG_pointer_type)
+	.byte	0x4	# DW_AT_byte_size
+	.long	0x6e	# DW_AT_type
+	.uleb128 0x9	# (DIE (0x6e) DW_TAG_structure_type)
+	.ascii "C\0"	# DW_AT_name
+	.byte	0x8	# DW_AT_byte_size
+	.byte	0x1	# DW_AT_decl_file (gdb.dwarf2/member-ptr-forwardref.cc)
+	.byte	0x16	# DW_AT_decl_line
+	.long	0x85	# DW_AT_sibling
+	.uleb128 0xa	# (DIE (0x78) DW_TAG_member)
+	.ascii "fp\0"	# DW_AT_name
+	.byte	0x1	# DW_AT_decl_file (gdb.dwarf2/member-ptr-forwardref.cc)
+	.byte	0x17	# DW_AT_decl_line
+	.long	0x30	# DW_AT_type
+	.sleb128 0	# DW_AT_data_member_location
+	.byte	0x3	# DW_AT_accessibility
+	.byte	0x0	# end of children of DIE 0x6e
+	.uleb128 0x8	# (DIE (0x85) DW_TAG_pointer_type)
+	.byte	0x4	# DW_AT_byte_size
+	.long	0x51	# DW_AT_type
+	.uleb128 0xb	# (DIE (0x8b) DW_TAG_variable)
+	.ascii "fp\0"	# DW_AT_name
+	.byte	0x1	# DW_AT_decl_file (gdb.dwarf2/member-ptr-forwardref.cc)
+	.byte	0x14	# DW_AT_decl_line
+	.long	0x25	# DW_AT_type
+	.byte	0x1	# DW_AT_external
+	.byte	0x5	# DW_AT_location
+	.byte	0x3	# DW_OP_addr
+	.long	fp
+	.uleb128 0xb	# (DIE (0x9c) DW_TAG_variable)
+	.ascii "c\0"	# DW_AT_name
+	.byte	0x1	# DW_AT_decl_file (gdb.dwarf2/member-ptr-forwardref.cc)
+	.byte	0x18	# DW_AT_decl_line
+	.long	0x6e	# DW_AT_type
+	.byte	0x1	# DW_AT_external
+	.byte	0x5	# DW_AT_location
+	.byte	0x3	# DW_OP_addr
+	.long	c
+	.byte	0x0	# end of children of DIE 0xb
+	.section	.debug_abbrev
+	.uleb128 0x1	# (abbrev code)
+	.uleb128 0x11	# (TAG: DW_TAG_compile_unit)
+	.byte	0x1	# DW_children_yes
+	.uleb128 0x25	# (DW_AT_producer)
+	.uleb128 0xe	# (DW_FORM_strp)
+	.uleb128 0x13	# (DW_AT_language)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x3	# (DW_AT_name)
+	.uleb128 0xe	# (DW_FORM_strp)
+	.uleb128 0x1b	# (DW_AT_comp_dir)
+	.uleb128 0xe	# (DW_FORM_strp)
+	.uleb128 0x11	# (DW_AT_low_pc)
+	.uleb128 0x1	# (DW_FORM_addr)
+	.uleb128 0x12	# (DW_AT_high_pc)
+	.uleb128 0x1	# (DW_FORM_addr)
+	.uleb128 0x10	# (DW_AT_stmt_list)
+	.uleb128 0x6	# (DW_FORM_data4)
+	.byte	0x0
+	.byte	0x0
+	.uleb128 0x2	# (abbrev code)
+	.uleb128 0x16	# (TAG: DW_TAG_typedef)
+	.byte	0x0	# DW_children_no
+	.uleb128 0x3	# (DW_AT_name)
+	.uleb128 0xe	# (DW_FORM_strp)
+	.uleb128 0x3a	# (DW_AT_decl_file)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x3b	# (DW_AT_decl_line)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x49	# (DW_AT_type)
+	.uleb128 0x13	# (DW_FORM_ref4)
+	.byte	0x0
+	.byte	0x0
+	.uleb128 0x3	# (abbrev code)
+	.uleb128 0x13	# (TAG: DW_TAG_structure_type)
+	.byte	0x1	# DW_children_yes
+	.uleb128 0xb	# (DW_AT_byte_size)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x3a	# (DW_AT_decl_file)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x3b	# (DW_AT_decl_line)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x1	# (DW_AT_sibling)
+	.uleb128 0x13	# (DW_FORM_ref4)
+	.byte	0x0
+	.byte	0x0
+	.uleb128 0x4	# (abbrev code)
+	.uleb128 0xd	# (TAG: DW_TAG_member)
+	.byte	0x0	# DW_children_no
+	.uleb128 0x3	# (DW_AT_name)
+	.uleb128 0xe	# (DW_FORM_strp)
+	.uleb128 0x3a	# (DW_AT_decl_file)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x3b	# (DW_AT_decl_line)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x49	# (DW_AT_type)
+	.uleb128 0x13	# (DW_FORM_ref4)
+	.uleb128 0x38	# (DW_AT_data_member_location)
+	.uleb128 0xd	# (DW_FORM_sdata)
+	.byte	0x0
+	.byte	0x0
+	.uleb128 0x5	# (abbrev code)
+	.uleb128 0x15	# (TAG: DW_TAG_subroutine_type)
+	.byte	0x1	# DW_children_yes
+	.uleb128 0x49	# (DW_AT_type)
+	.uleb128 0x13	# (DW_FORM_ref4)
+	.uleb128 0x1	# (DW_AT_sibling)
+	.uleb128 0x13	# (DW_FORM_ref4)
+	.byte	0x0
+	.byte	0x0
+	.uleb128 0x6	# (abbrev code)
+	.uleb128 0x5	# (TAG: DW_TAG_formal_parameter)
+	.byte	0x0	# DW_children_no
+	.uleb128 0x49	# (DW_AT_type)
+	.uleb128 0x13	# (DW_FORM_ref4)
+	.uleb128 0x34	# (DW_AT_artificial)
+	.uleb128 0xc	# (DW_FORM_flag)
+	.byte	0x0
+	.byte	0x0
+	.uleb128 0x7	# (abbrev code)
+	.uleb128 0x24	# (TAG: DW_TAG_base_type)
+	.byte	0x0	# DW_children_no
+	.uleb128 0xb	# (DW_AT_byte_size)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x3e	# (DW_AT_encoding)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x3	# (DW_AT_name)
+	.uleb128 0x8	# (DW_FORM_string)
+	.byte	0x0
+	.byte	0x0
+	.uleb128 0x8	# (abbrev code)
+	.uleb128 0xf	# (TAG: DW_TAG_pointer_type)
+	.byte	0x0	# DW_children_no
+	.uleb128 0xb	# (DW_AT_byte_size)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x49	# (DW_AT_type)
+	.uleb128 0x13	# (DW_FORM_ref4)
+	.byte	0x0
+	.byte	0x0
+	.uleb128 0x9	# (abbrev code)
+	.uleb128 0x13	# (TAG: DW_TAG_structure_type)
+	.byte	0x1	# DW_children_yes
+	.uleb128 0x3	# (DW_AT_name)
+	.uleb128 0x8	# (DW_FORM_string)
+	.uleb128 0xb	# (DW_AT_byte_size)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x3a	# (DW_AT_decl_file)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x3b	# (DW_AT_decl_line)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x1	# (DW_AT_sibling)
+	.uleb128 0x13	# (DW_FORM_ref4)
+	.byte	0x0
+	.byte	0x0
+	.uleb128 0xa	# (abbrev code)
+	.uleb128 0xd	# (TAG: DW_TAG_member)
+	.byte	0x0	# DW_children_no
+	.uleb128 0x3	# (DW_AT_name)
+	.uleb128 0x8	# (DW_FORM_string)
+	.uleb128 0x3a	# (DW_AT_decl_file)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x3b	# (DW_AT_decl_line)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x49	# (DW_AT_type)
+	.uleb128 0x13	# (DW_FORM_ref4)
+	.uleb128 0x38	# (DW_AT_data_member_location)
+	.uleb128 0xd	# (DW_FORM_sdata)
+	.uleb128 0x32	# (DW_AT_accessibility)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.byte	0x0
+	.byte	0x0
+	.uleb128 0xb	# (abbrev code)
+	.uleb128 0x34	# (TAG: DW_TAG_variable)
+	.byte	0x0	# DW_children_no
+	.uleb128 0x3	# (DW_AT_name)
+	.uleb128 0x8	# (DW_FORM_string)
+	.uleb128 0x3a	# (DW_AT_decl_file)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x3b	# (DW_AT_decl_line)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x49	# (DW_AT_type)
+	.uleb128 0x13	# (DW_FORM_ref4)
+	.uleb128 0x3f	# (DW_AT_external)
+	.uleb128 0xc	# (DW_FORM_flag)
+	.uleb128 0x2	# (DW_AT_location)
+	.uleb128 0xa	# (DW_FORM_block1)
+	.byte	0x0
+	.byte	0x0
+	.byte	0x0
+	.section	.debug_pubnames,"",@progbits
+	.long	0x1b	# Length of Public Names Info
+	.value	0x2	# DWARF Version
+	.long	.Ldebug_info0	# Offset of Compilation Unit Info
+	.long	0xad	# Compilation Unit Length
+	.long	0x8b	# DIE offset
+	.ascii "fp\0"	# external name
+	.long	0x9c	# DIE offset
+	.ascii "c\0"	# external name
+	.long	0x0
+	.section	.debug_pubtypes,"",@progbits
+	.long	0x1d	# Length of Public Type Names Info
+	.value	0x2	# DWARF Version
+	.long	.Ldebug_info0	# Offset of Compilation Unit Info
+	.long	0xad	# Compilation Unit Length
+	.long	0x25	# DIE offset
+	.ascii "fp_t\0"	# external name
+	.long	0x6e	# DIE offset
+	.ascii "C\0"	# external name
+	.long	0x0
+	.section	.debug_str,"MS",@progbits,1
+.LASF5:
+	.string	"fp_t"
+.LASF2:
+	.string	"GNU C++ 4.4.2 20091222 (Red Hat 4.4.2-20)"
+.LASF0:
+	.string	"__pfn"
+.LASF4:
+	.string	"gdb/testsuite"
+.LASF3:
+	.string	"gdb.dwarf2/member-ptr-forwardref.cc"
+.LASF1:
+	.string	"__delta"
+	.ident	"GCC: (GNU) 4.4.2 20091222 (Red Hat 4.4.2-20)"
+	.section	.note.GNU-stack,"",@progbits
--- /dev/null
+++ b/gdb/testsuite/gdb.dwarf2/member-ptr-forwardref.exp
@@ -0,0 +1,48 @@
+# Copyright 2010 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/>.
+
+# 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  
+}
+
+if { [skip_cplus_tests] } { continue }
+
+set testfile member-ptr-forwardref
+set executable ${testfile}
+set binfile ${objdir}/${subdir}/${executable}.x
+
+if { [gdb_compile "${srcdir}/${subdir}/${testfile}.S" ${binfile} object {debug}] != "" } {
+    untested ${testfile}.exp
+    return -1
+}
+
+gdb_exit
+gdb_start
+gdb_reinitialize_dir $srcdir/$subdir
+
+# Be sure to set cp-abi before ${binfile} gets loaded
+gdb_test "set cp-abi gnu-v3"
+gdb_test "show cp-abi" {The currently selected C\+\+ ABI is "gnu-v3".*}
+
+gdb_load ${binfile}
+
+gdb_test "ptype c" "type = class C {\[\r\n \t\]*int \\(C::\\*fp\\)\\(C \\*\\);\[\r\n \t\]*}"

Re: [patch] Fix crash on DWARF C++ forward reference

[Tom Tromey]

>>>>> "Jan" == Jan Kratochvil <jan.kratochvil@redhat.com> writes:

Jan> the problem is based on the testcase contained in GCC PR debug/28767
Jan> by Daniel J. with specially crafted forward-reference resulting in
Jan> a double-entry to quirk_gcc_member_function_pointer for the same DIE which
Jan> crashes GDB.  Problem has been seen in practice.

See http://sourceware.org/bugzilla/show_bug.cgi?id=11199

Jan> I understand the solution is not nice but I hope the DWARF reading
Jan> functions do not access much the content of referenced TYPEs.

I also came up with a patch.  What do you think of the appended?

My concern with your patch is what happens if
quirk_gcc_member_function_pointer bails out after it sets the DIE type?
It seems to me that if __pfn refers to its enclosing struct type, then
it could refer to the wrong type in the end.

My patch also suffers from the (IMO low) risk of the DWARF code seeing a
struct type at one point and a member function at another.  Also,
smashing the type seems pretty ugly.

Tom

diff --git a/gdb/dwarf2read.c b/gdb/dwarf2read.c
index db51653..3bc72ac 100644
--- a/gdb/dwarf2read.c
+++ b/gdb/dwarf2read.c
@@ -4892,68 +4892,48 @@ is_vtable_name (const char *name, struct dwarf2_cu *cu)
 }
 
 /* GCC outputs unnamed structures that are really pointers to member
-   functions, with the ABI-specified layout.  If DIE (from CU) describes
-   such a structure, set its type, and return nonzero.  Otherwise return
-   zero.
+   functions, with the ABI-specified layout.  If TYPE describes
+   such a structure, smash it into a member function type.
 
    GCC shouldn't do this; it should just output pointer to member DIEs.
    This is GCC PR debug/28767.  */
 
-static struct type *
-quirk_gcc_member_function_pointer (struct die_info *die, struct dwarf2_cu *cu)
+static void
+quirk_gcc_member_function_pointer (struct type *type, struct objfile *objfile)
 {
-  struct objfile *objfile = cu->objfile;
-  struct type *type;
-  struct die_info *pfn_die, *delta_die;
-  struct attribute *pfn_name, *delta_name;
-  struct type *pfn_type, *domain_type;
+  struct type *pfn_type, *domain_type, *new_type;
 
   /* Check for a structure with no name and two children.  */
-  if (die->tag != DW_TAG_structure_type
-      || dwarf2_attr (die, DW_AT_name, cu) != NULL
-      || die->child == NULL
-      || die->child->sibling == NULL
-      || (die->child->sibling->sibling != NULL
-	  && die->child->sibling->sibling->tag != DW_TAG_padding))
-    return NULL;
+  if (TYPE_CODE (type) != TYPE_CODE_STRUCT || TYPE_NFIELDS (type) != 2)
+    return;
 
   /* Check for __pfn and __delta members.  */
-  pfn_die = die->child;
-  pfn_name = dwarf2_attr (pfn_die, DW_AT_name, cu);
-  if (pfn_die->tag != DW_TAG_member
-      || pfn_name == NULL
-      || DW_STRING (pfn_name) == NULL
-      || strcmp ("__pfn", DW_STRING (pfn_name)) != 0)
-    return NULL;
-
-  delta_die = pfn_die->sibling;
-  delta_name = dwarf2_attr (delta_die, DW_AT_name, cu);
-  if (delta_die->tag != DW_TAG_member
-      || delta_name == NULL
-      || DW_STRING (delta_name) == NULL
-      || strcmp ("__delta", DW_STRING (delta_name)) != 0)
-    return NULL;
+  if (TYPE_FIELD_NAME (type, 0) == NULL
+      || strcmp (TYPE_FIELD_NAME (type, 0), "__pfn") != 0
+      || TYPE_FIELD_NAME (type, 1) == NULL
+      || strcmp (TYPE_FIELD_NAME (type, 1), "__delta") != 0)
+    return;
 
   /* Find the type of the method.  */
-  pfn_type = die_type (pfn_die, cu);
+  pfn_type = TYPE_FIELD_TYPE (type, 0);
   if (pfn_type == NULL
       || TYPE_CODE (pfn_type) != TYPE_CODE_PTR
       || TYPE_CODE (TYPE_TARGET_TYPE (pfn_type)) != TYPE_CODE_FUNC)
-    return NULL;
+    return;
 
   /* Look for the "this" argument.  */
   pfn_type = TYPE_TARGET_TYPE (pfn_type);
   if (TYPE_NFIELDS (pfn_type) == 0
+      /* || TYPE_FIELD_TYPE (pfn_type, 0) == NULL */
       || TYPE_CODE (TYPE_FIELD_TYPE (pfn_type, 0)) != TYPE_CODE_PTR)
-    return NULL;
+    return;
 
   domain_type = TYPE_TARGET_TYPE (TYPE_FIELD_TYPE (pfn_type, 0));
-  type = alloc_type (objfile);
-  smash_to_method_type (type, domain_type, TYPE_TARGET_TYPE (pfn_type),
+  new_type = alloc_type (objfile);
+  smash_to_method_type (new_type, domain_type, TYPE_TARGET_TYPE (pfn_type),
 			TYPE_FIELDS (pfn_type), TYPE_NFIELDS (pfn_type),
 			TYPE_VARARGS (pfn_type));
-  type = lookup_methodptr_type (type);
-  return set_die_type (die, type, cu);
+  smash_to_methodptr_type (type, new_type);
 }
 
 /* Called when we find the DIE that starts a structure or union scope
@@ -4981,10 +4961,6 @@ read_structure_type (struct die_info *die, struct dwarf2_cu *cu)
   char *name;
   struct cleanup *back_to = make_cleanup (null_cleanup, 0);
 
-  type = quirk_gcc_member_function_pointer (die, cu);
-  if (type)
-    return type;
-
   /* If the definition of this type lives in .debug_types, read that type.
      Don't follow DW_AT_specification though, that will take us back up
      the chain and we want to go down.  */
@@ -5163,6 +5139,8 @@ read_structure_type (struct die_info *die, struct dwarf2_cu *cu)
 	}
     }
 
+  quirk_gcc_member_function_pointer (type, cu->objfile);
+
   do_cleanups (back_to);
   return type;
 }
diff --git a/gdb/gdbtypes.c b/gdb/gdbtypes.c
index 117606a..2ff8647 100644
--- a/gdb/gdbtypes.c
+++ b/gdb/gdbtypes.c
@@ -673,10 +673,7 @@ lookup_methodptr_type (struct type *to_type)
   struct type *mtype;
 
   mtype = alloc_type_copy (to_type);
-  TYPE_TARGET_TYPE (mtype) = to_type;
-  TYPE_DOMAIN_TYPE (mtype) = TYPE_DOMAIN_TYPE (to_type);
-  TYPE_LENGTH (mtype) = cplus_method_ptr_size (to_type);
-  TYPE_CODE (mtype) = TYPE_CODE_METHODPTR;
+  smash_to_methodptr_type (mtype, to_type);
   return mtype;
 }
 
@@ -981,6 +978,22 @@ smash_to_memberptr_type (struct type *type, struct type *domain,
   TYPE_CODE (type) = TYPE_CODE_MEMBERPTR;
 }
 
+/* Smash TYPE to be a type of pointer to methods type TO_TYPE.
+
+   When "smashing" the type, we preserve the objfile that the old type
+   pointed to, since we aren't changing where the type is actually
+   allocated.  */
+
+void
+smash_to_methodptr_type (struct type *type, struct type *to_type)
+{
+  smash_type (type);
+  TYPE_TARGET_TYPE (type) = to_type;
+  TYPE_DOMAIN_TYPE (type) = TYPE_DOMAIN_TYPE (to_type);
+  TYPE_LENGTH (type) = cplus_method_ptr_size (to_type);
+  TYPE_CODE (type) = TYPE_CODE_METHODPTR;
+}
+
 /* Smash TYPE to be a type of method of DOMAIN with type TO_TYPE.
    METHOD just means `function that gets an extra "this" argument'.
 
diff --git a/gdb/gdbtypes.h b/gdb/gdbtypes.h
index 380f72a..72968a5 100644
--- a/gdb/gdbtypes.h
+++ b/gdb/gdbtypes.h
@@ -1312,6 +1312,8 @@ extern void smash_to_method_type (struct type *type, struct type *domain,
 extern void smash_to_memberptr_type (struct type *, struct type *,
 				     struct type *);
 
+extern void smash_to_methodptr_type (struct type *, struct type *);
+
 extern struct type *allocate_stub_method (struct type *);
 
 extern char *type_name_no_tag (const struct type *);

Re: [patch] Fix crash on DWARF C++ forward reference

[Jan Kratochvil]

On Fri, 22 Jan 2010 02:42:22 +0100, Tom Tromey wrote:
> I also came up with a patch.  What do you think of the appended?

OK, it is a better approach.  I cannot find a countercase.


Regards,
Jan

Re: [patch] Fix crash on DWARF C++ forward reference

[Tom Tromey]

>>>>> "Jan" == Jan Kratochvil <jan.kratochvil@redhat.com> writes:

Jan> On Fri, 22 Jan 2010 02:42:22 +0100, Tom Tromey wrote:
>> I also came up with a patch.  What do you think of the appended?

Jan> OK, it is a better approach.  I cannot find a countercase.

Thanks.  Here is what I am checking in.
Built and regtested on x86-64 (compile farm).

Tom

2010-01-22  Tom Tromey  <tromey@redhat.com>

	PR symtab/11199:
	* dwarf2read.c (quirk_gcc_member_function_pointer): Change return
	type and arguments.  Use smash_to_methodptr_type.
	(read_structure_type): Call quirk_gcc_member_function_pointer
	later.
	* gdbtypes.h (smash_to_methodptr_type): Declare.
	* gdbtypes.c (smash_to_methodptr_type): New function.
	(lookup_methodptr_type): Use it.

2010-01-22  Jan Kratochvil  <jan.kratochvil@redhat.com>

	PR symtab/11199:
	* gdb.dwarf2/member-ptr-forwardref.exp,
	gdb.dwarf2/member-ptr-forwardref.S: New.

Index: dwarf2read.c
===================================================================
RCS file: /cvs/src/src/gdb/dwarf2read.c,v
retrieving revision 1.350
diff -u -r1.350 dwarf2read.c
--- dwarf2read.c	20 Jan 2010 02:05:03 -0000	1.350
+++ dwarf2read.c	22 Jan 2010 17:01:06 -0000
@@ -4892,68 +4892,48 @@
 }
 
 /* GCC outputs unnamed structures that are really pointers to member
-   functions, with the ABI-specified layout.  If DIE (from CU) describes
-   such a structure, set its type, and return nonzero.  Otherwise return
-   zero.
+   functions, with the ABI-specified layout.  If TYPE describes
+   such a structure, smash it into a member function type.
 
    GCC shouldn't do this; it should just output pointer to member DIEs.
    This is GCC PR debug/28767.  */
 
-static struct type *
-quirk_gcc_member_function_pointer (struct die_info *die, struct dwarf2_cu *cu)
+static void
+quirk_gcc_member_function_pointer (struct type *type, struct objfile *objfile)
 {
-  struct objfile *objfile = cu->objfile;
-  struct type *type;
-  struct die_info *pfn_die, *delta_die;
-  struct attribute *pfn_name, *delta_name;
-  struct type *pfn_type, *domain_type;
+  struct type *pfn_type, *domain_type, *new_type;
 
   /* Check for a structure with no name and two children.  */
-  if (die->tag != DW_TAG_structure_type
-      || dwarf2_attr (die, DW_AT_name, cu) != NULL
-      || die->child == NULL
-      || die->child->sibling == NULL
-      || (die->child->sibling->sibling != NULL
-	  && die->child->sibling->sibling->tag != DW_TAG_padding))
-    return NULL;
+  if (TYPE_CODE (type) != TYPE_CODE_STRUCT || TYPE_NFIELDS (type) != 2)
+    return;
 
   /* Check for __pfn and __delta members.  */
-  pfn_die = die->child;
-  pfn_name = dwarf2_attr (pfn_die, DW_AT_name, cu);
-  if (pfn_die->tag != DW_TAG_member
-      || pfn_name == NULL
-      || DW_STRING (pfn_name) == NULL
-      || strcmp ("__pfn", DW_STRING (pfn_name)) != 0)
-    return NULL;
-
-  delta_die = pfn_die->sibling;
-  delta_name = dwarf2_attr (delta_die, DW_AT_name, cu);
-  if (delta_die->tag != DW_TAG_member
-      || delta_name == NULL
-      || DW_STRING (delta_name) == NULL
-      || strcmp ("__delta", DW_STRING (delta_name)) != 0)
-    return NULL;
+  if (TYPE_FIELD_NAME (type, 0) == NULL
+      || strcmp (TYPE_FIELD_NAME (type, 0), "__pfn") != 0
+      || TYPE_FIELD_NAME (type, 1) == NULL
+      || strcmp (TYPE_FIELD_NAME (type, 1), "__delta") != 0)
+    return;
 
   /* Find the type of the method.  */
-  pfn_type = die_type (pfn_die, cu);
+  pfn_type = TYPE_FIELD_TYPE (type, 0);
   if (pfn_type == NULL
       || TYPE_CODE (pfn_type) != TYPE_CODE_PTR
       || TYPE_CODE (TYPE_TARGET_TYPE (pfn_type)) != TYPE_CODE_FUNC)
-    return NULL;
+    return;
 
   /* Look for the "this" argument.  */
   pfn_type = TYPE_TARGET_TYPE (pfn_type);
   if (TYPE_NFIELDS (pfn_type) == 0
+      /* || TYPE_FIELD_TYPE (pfn_type, 0) == NULL */
       || TYPE_CODE (TYPE_FIELD_TYPE (pfn_type, 0)) != TYPE_CODE_PTR)
-    return NULL;
+    return;
 
   domain_type = TYPE_TARGET_TYPE (TYPE_FIELD_TYPE (pfn_type, 0));
-  type = alloc_type (objfile);
-  smash_to_method_type (type, domain_type, TYPE_TARGET_TYPE (pfn_type),
+  new_type = alloc_type (objfile);
+  smash_to_method_type (new_type, domain_type, TYPE_TARGET_TYPE (pfn_type),
 			TYPE_FIELDS (pfn_type), TYPE_NFIELDS (pfn_type),
 			TYPE_VARARGS (pfn_type));
-  type = lookup_methodptr_type (type);
-  return set_die_type (die, type, cu);
+  smash_to_methodptr_type (type, new_type);
 }
 
 /* Called when we find the DIE that starts a structure or union scope
@@ -4981,10 +4961,6 @@
   char *name;
   struct cleanup *back_to = make_cleanup (null_cleanup, 0);
 
-  type = quirk_gcc_member_function_pointer (die, cu);
-  if (type)
-    return type;
-
   /* If the definition of this type lives in .debug_types, read that type.
      Don't follow DW_AT_specification though, that will take us back up
      the chain and we want to go down.  */
@@ -5163,6 +5139,8 @@
 	}
     }
 
+  quirk_gcc_member_function_pointer (type, cu->objfile);
+
   do_cleanups (back_to);
   return type;
 }
Index: gdbtypes.c
===================================================================
RCS file: /cvs/src/src/gdb/gdbtypes.c,v
retrieving revision 1.184
diff -u -r1.184 gdbtypes.c
--- gdbtypes.c	18 Jan 2010 20:54:34 -0000	1.184
+++ gdbtypes.c	22 Jan 2010 17:01:07 -0000
@@ -673,10 +673,7 @@
   struct type *mtype;
 
   mtype = alloc_type_copy (to_type);
-  TYPE_TARGET_TYPE (mtype) = to_type;
-  TYPE_DOMAIN_TYPE (mtype) = TYPE_DOMAIN_TYPE (to_type);
-  TYPE_LENGTH (mtype) = cplus_method_ptr_size (to_type);
-  TYPE_CODE (mtype) = TYPE_CODE_METHODPTR;
+  smash_to_methodptr_type (mtype, to_type);
   return mtype;
 }
 
@@ -981,6 +978,22 @@
   TYPE_CODE (type) = TYPE_CODE_MEMBERPTR;
 }
 
+/* Smash TYPE to be a type of pointer to methods type TO_TYPE.
+
+   When "smashing" the type, we preserve the objfile that the old type
+   pointed to, since we aren't changing where the type is actually
+   allocated.  */
+
+void
+smash_to_methodptr_type (struct type *type, struct type *to_type)
+{
+  smash_type (type);
+  TYPE_TARGET_TYPE (type) = to_type;
+  TYPE_DOMAIN_TYPE (type) = TYPE_DOMAIN_TYPE (to_type);
+  TYPE_LENGTH (type) = cplus_method_ptr_size (to_type);
+  TYPE_CODE (type) = TYPE_CODE_METHODPTR;
+}
+
 /* Smash TYPE to be a type of method of DOMAIN with type TO_TYPE.
    METHOD just means `function that gets an extra "this" argument'.
 
Index: gdbtypes.h
===================================================================
RCS file: /cvs/src/src/gdb/gdbtypes.h,v
retrieving revision 1.120
diff -u -r1.120 gdbtypes.h
--- gdbtypes.h	18 Jan 2010 20:54:34 -0000	1.120
+++ gdbtypes.h	22 Jan 2010 17:01:07 -0000
@@ -1312,6 +1312,8 @@
 extern void smash_to_memberptr_type (struct type *, struct type *,
 				     struct type *);
 
+extern void smash_to_methodptr_type (struct type *, struct type *);
+
 extern struct type *allocate_stub_method (struct type *);
 
 extern char *type_name_no_tag (const struct type *);
Index: testsuite/gdb.dwarf2/member-ptr-forwardref.S
===================================================================
RCS file: testsuite/gdb.dwarf2/member-ptr-forwardref.S
diff -N testsuite/gdb.dwarf2/member-ptr-forwardref.S
--- /dev/null	1 Jan 1970 00:00:00 -0000
+++ testsuite/gdb.dwarf2/member-ptr-forwardref.S	22 Jan 2010 17:01:08 -0000
@@ -0,0 +1,327 @@
+/* This testcase is part of GDB, the GNU debugger.
+
+   Copyright 2010 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/>.  */
+
+/* The goal of this test is to provide anonymous DW_TAG_structure_type
+   containing __pfn + __delta (read in by quirk_gcc_member_function_pointer)
+   before DW_TAG_structure_type of "class C" to exploit the forward reference
+   through "__pfn" and back from DW_TAG_member "fp" of "class C".  As the
+   compiler may place the DIEs in arbitrary order they are rather prepared as
+   a .S file.
+
+   class C;
+   typedef int (C::*fp_t) ();
+   fp_t fp;
+   class C
+     {
+       int (C::*fp) ();
+     } c;  */
+
+	.file	"member-ptr-forwardref.cc"
+	.section	.debug_abbrev,"",@progbits
+.Ldebug_abbrev0:
+	.section	.debug_info,"",@progbits
+.Ldebug_info0:
+	.section	.debug_line,"",@progbits
+.Ldebug_line0:
+	.text
+.Ltext0:
+.globl fp
+	.bss
+	.align 4
+	.type	fp, @object
+	.size	fp, 8
+fp:
+	.zero	8
+.globl c
+	.align 4
+	.type	c, @object
+	.size	c, 8
+c:
+	.zero	8
+	.text
+.Letext0:
+	.file 1 "gdb.dwarf2/member-ptr-forwardref.cc"
+	.section	.debug_info
+	.long	0xa9	# Length of Compilation Unit Info
+	.value	0x3	# DWARF version number
+	.long	.Ldebug_abbrev0	# Offset Into Abbrev. Section
+	.byte	0x4	# Pointer Size (in bytes)
+	.uleb128 0x1	# (DIE (0xb) DW_TAG_compile_unit)
+	.long	.LASF2	# DW_AT_producer: "GNU C++ 4.4.2 20091222 (Red Hat 4.4.2-20)"
+	.byte	0x4	# DW_AT_language
+	.long	.LASF3	# DW_AT_name: "gdb.dwarf2/member-ptr-forwardref.cc"
+	.long	.LASF4	# DW_AT_comp_dir: "gdb/testsuite"
+	.long	.Ltext0	# DW_AT_low_pc
+	.long	.Letext0	# DW_AT_high_pc
+	.long	.Ldebug_line0	# DW_AT_stmt_list
+	.uleb128 0x2	# (DIE (0x25) DW_TAG_typedef)
+	.long	.LASF5	# DW_AT_name: "fp_t"
+	.byte	0x1	# DW_AT_decl_file (gdb.dwarf2/member-ptr-forwardref.cc)
+	.byte	0x13	# DW_AT_decl_line
+	.long	0x30	# DW_AT_type
+	.uleb128 0x3	# (DIE (0x30) DW_TAG_structure_type)
+	.byte	0x8	# DW_AT_byte_size
+	.byte	0x1	# DW_AT_decl_file (gdb.dwarf2/member-ptr-forwardref.cc)
+	.byte	0x13	# DW_AT_decl_line
+	.long	0x51	# DW_AT_sibling
+	.uleb128 0x4	# (DIE (0x38) DW_TAG_member)
+	.long	.LASF0	# DW_AT_name: "__pfn"
+	.byte	0x1	# DW_AT_decl_file (gdb.dwarf2/member-ptr-forwardref.cc)
+	.byte	0x13	# DW_AT_decl_line
+	.long	0x85	# DW_AT_type
+	.sleb128 0	# DW_AT_data_member_location
+	.uleb128 0x4	# (DIE (0x44) DW_TAG_member)
+	.long	.LASF1	# DW_AT_name: "__delta"
+	.byte	0x1	# DW_AT_decl_file (gdb.dwarf2/member-ptr-forwardref.cc)
+	.byte	0x13	# DW_AT_decl_line
+	.long	0x61	# DW_AT_type
+	.sleb128 4	# DW_AT_data_member_location
+	.byte	0x0	# end of children of DIE 0x30
+	.uleb128 0x5	# (DIE (0x51) DW_TAG_subroutine_type)
+	.long	0x61	# DW_AT_type
+	.long	0x61	# DW_AT_sibling
+	.uleb128 0x6	# (DIE (0x5a) DW_TAG_formal_parameter)
+	.long	0x68	# DW_AT_type
+	.byte	0x1	# DW_AT_artificial
+	.byte	0x0	# end of children of DIE 0x51
+	.uleb128 0x7	# (DIE (0x61) DW_TAG_base_type)
+	.byte	0x4	# DW_AT_byte_size
+	.byte	0x5	# DW_AT_encoding
+	.ascii "int\0"	# DW_AT_name
+	.uleb128 0x8	# (DIE (0x68) DW_TAG_pointer_type)
+	.byte	0x4	# DW_AT_byte_size
+	.long	0x6e	# DW_AT_type
+	.uleb128 0x9	# (DIE (0x6e) DW_TAG_structure_type)
+	.ascii "C\0"	# DW_AT_name
+	.byte	0x8	# DW_AT_byte_size
+	.byte	0x1	# DW_AT_decl_file (gdb.dwarf2/member-ptr-forwardref.cc)
+	.byte	0x16	# DW_AT_decl_line
+	.long	0x85	# DW_AT_sibling
+	.uleb128 0xa	# (DIE (0x78) DW_TAG_member)
+	.ascii "fp\0"	# DW_AT_name
+	.byte	0x1	# DW_AT_decl_file (gdb.dwarf2/member-ptr-forwardref.cc)
+	.byte	0x17	# DW_AT_decl_line
+	.long	0x30	# DW_AT_type
+	.sleb128 0	# DW_AT_data_member_location
+	.byte	0x3	# DW_AT_accessibility
+	.byte	0x0	# end of children of DIE 0x6e
+	.uleb128 0x8	# (DIE (0x85) DW_TAG_pointer_type)
+	.byte	0x4	# DW_AT_byte_size
+	.long	0x51	# DW_AT_type
+	.uleb128 0xb	# (DIE (0x8b) DW_TAG_variable)
+	.ascii "fp\0"	# DW_AT_name
+	.byte	0x1	# DW_AT_decl_file (gdb.dwarf2/member-ptr-forwardref.cc)
+	.byte	0x14	# DW_AT_decl_line
+	.long	0x25	# DW_AT_type
+	.byte	0x1	# DW_AT_external
+	.byte	0x5	# DW_AT_location
+	.byte	0x3	# DW_OP_addr
+	.long	fp
+	.uleb128 0xb	# (DIE (0x9c) DW_TAG_variable)
+	.ascii "c\0"	# DW_AT_name
+	.byte	0x1	# DW_AT_decl_file (gdb.dwarf2/member-ptr-forwardref.cc)
+	.byte	0x18	# DW_AT_decl_line
+	.long	0x6e	# DW_AT_type
+	.byte	0x1	# DW_AT_external
+	.byte	0x5	# DW_AT_location
+	.byte	0x3	# DW_OP_addr
+	.long	c
+	.byte	0x0	# end of children of DIE 0xb
+	.section	.debug_abbrev
+	.uleb128 0x1	# (abbrev code)
+	.uleb128 0x11	# (TAG: DW_TAG_compile_unit)
+	.byte	0x1	# DW_children_yes
+	.uleb128 0x25	# (DW_AT_producer)
+	.uleb128 0xe	# (DW_FORM_strp)
+	.uleb128 0x13	# (DW_AT_language)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x3	# (DW_AT_name)
+	.uleb128 0xe	# (DW_FORM_strp)
+	.uleb128 0x1b	# (DW_AT_comp_dir)
+	.uleb128 0xe	# (DW_FORM_strp)
+	.uleb128 0x11	# (DW_AT_low_pc)
+	.uleb128 0x1	# (DW_FORM_addr)
+	.uleb128 0x12	# (DW_AT_high_pc)
+	.uleb128 0x1	# (DW_FORM_addr)
+	.uleb128 0x10	# (DW_AT_stmt_list)
+	.uleb128 0x6	# (DW_FORM_data4)
+	.byte	0x0
+	.byte	0x0
+	.uleb128 0x2	# (abbrev code)
+	.uleb128 0x16	# (TAG: DW_TAG_typedef)
+	.byte	0x0	# DW_children_no
+	.uleb128 0x3	# (DW_AT_name)
+	.uleb128 0xe	# (DW_FORM_strp)
+	.uleb128 0x3a	# (DW_AT_decl_file)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x3b	# (DW_AT_decl_line)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x49	# (DW_AT_type)
+	.uleb128 0x13	# (DW_FORM_ref4)
+	.byte	0x0
+	.byte	0x0
+	.uleb128 0x3	# (abbrev code)
+	.uleb128 0x13	# (TAG: DW_TAG_structure_type)
+	.byte	0x1	# DW_children_yes
+	.uleb128 0xb	# (DW_AT_byte_size)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x3a	# (DW_AT_decl_file)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x3b	# (DW_AT_decl_line)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x1	# (DW_AT_sibling)
+	.uleb128 0x13	# (DW_FORM_ref4)
+	.byte	0x0
+	.byte	0x0
+	.uleb128 0x4	# (abbrev code)
+	.uleb128 0xd	# (TAG: DW_TAG_member)
+	.byte	0x0	# DW_children_no
+	.uleb128 0x3	# (DW_AT_name)
+	.uleb128 0xe	# (DW_FORM_strp)
+	.uleb128 0x3a	# (DW_AT_decl_file)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x3b	# (DW_AT_decl_line)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x49	# (DW_AT_type)
+	.uleb128 0x13	# (DW_FORM_ref4)
+	.uleb128 0x38	# (DW_AT_data_member_location)
+	.uleb128 0xd	# (DW_FORM_sdata)
+	.byte	0x0
+	.byte	0x0
+	.uleb128 0x5	# (abbrev code)
+	.uleb128 0x15	# (TAG: DW_TAG_subroutine_type)
+	.byte	0x1	# DW_children_yes
+	.uleb128 0x49	# (DW_AT_type)
+	.uleb128 0x13	# (DW_FORM_ref4)
+	.uleb128 0x1	# (DW_AT_sibling)
+	.uleb128 0x13	# (DW_FORM_ref4)
+	.byte	0x0
+	.byte	0x0
+	.uleb128 0x6	# (abbrev code)
+	.uleb128 0x5	# (TAG: DW_TAG_formal_parameter)
+	.byte	0x0	# DW_children_no
+	.uleb128 0x49	# (DW_AT_type)
+	.uleb128 0x13	# (DW_FORM_ref4)
+	.uleb128 0x34	# (DW_AT_artificial)
+	.uleb128 0xc	# (DW_FORM_flag)
+	.byte	0x0
+	.byte	0x0
+	.uleb128 0x7	# (abbrev code)
+	.uleb128 0x24	# (TAG: DW_TAG_base_type)
+	.byte	0x0	# DW_children_no
+	.uleb128 0xb	# (DW_AT_byte_size)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x3e	# (DW_AT_encoding)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x3	# (DW_AT_name)
+	.uleb128 0x8	# (DW_FORM_string)
+	.byte	0x0
+	.byte	0x0
+	.uleb128 0x8	# (abbrev code)
+	.uleb128 0xf	# (TAG: DW_TAG_pointer_type)
+	.byte	0x0	# DW_children_no
+	.uleb128 0xb	# (DW_AT_byte_size)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x49	# (DW_AT_type)
+	.uleb128 0x13	# (DW_FORM_ref4)
+	.byte	0x0
+	.byte	0x0
+	.uleb128 0x9	# (abbrev code)
+	.uleb128 0x13	# (TAG: DW_TAG_structure_type)
+	.byte	0x1	# DW_children_yes
+	.uleb128 0x3	# (DW_AT_name)
+	.uleb128 0x8	# (DW_FORM_string)
+	.uleb128 0xb	# (DW_AT_byte_size)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x3a	# (DW_AT_decl_file)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x3b	# (DW_AT_decl_line)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x1	# (DW_AT_sibling)
+	.uleb128 0x13	# (DW_FORM_ref4)
+	.byte	0x0
+	.byte	0x0
+	.uleb128 0xa	# (abbrev code)
+	.uleb128 0xd	# (TAG: DW_TAG_member)
+	.byte	0x0	# DW_children_no
+	.uleb128 0x3	# (DW_AT_name)
+	.uleb128 0x8	# (DW_FORM_string)
+	.uleb128 0x3a	# (DW_AT_decl_file)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x3b	# (DW_AT_decl_line)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x49	# (DW_AT_type)
+	.uleb128 0x13	# (DW_FORM_ref4)
+	.uleb128 0x38	# (DW_AT_data_member_location)
+	.uleb128 0xd	# (DW_FORM_sdata)
+	.uleb128 0x32	# (DW_AT_accessibility)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.byte	0x0
+	.byte	0x0
+	.uleb128 0xb	# (abbrev code)
+	.uleb128 0x34	# (TAG: DW_TAG_variable)
+	.byte	0x0	# DW_children_no
+	.uleb128 0x3	# (DW_AT_name)
+	.uleb128 0x8	# (DW_FORM_string)
+	.uleb128 0x3a	# (DW_AT_decl_file)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x3b	# (DW_AT_decl_line)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x49	# (DW_AT_type)
+	.uleb128 0x13	# (DW_FORM_ref4)
+	.uleb128 0x3f	# (DW_AT_external)
+	.uleb128 0xc	# (DW_FORM_flag)
+	.uleb128 0x2	# (DW_AT_location)
+	.uleb128 0xa	# (DW_FORM_block1)
+	.byte	0x0
+	.byte	0x0
+	.byte	0x0
+	.section	.debug_pubnames,"",@progbits
+	.long	0x1b	# Length of Public Names Info
+	.value	0x2	# DWARF Version
+	.long	.Ldebug_info0	# Offset of Compilation Unit Info
+	.long	0xad	# Compilation Unit Length
+	.long	0x8b	# DIE offset
+	.ascii "fp\0"	# external name
+	.long	0x9c	# DIE offset
+	.ascii "c\0"	# external name
+	.long	0x0
+	.section	.debug_pubtypes,"",@progbits
+	.long	0x1d	# Length of Public Type Names Info
+	.value	0x2	# DWARF Version
+	.long	.Ldebug_info0	# Offset of Compilation Unit Info
+	.long	0xad	# Compilation Unit Length
+	.long	0x25	# DIE offset
+	.ascii "fp_t\0"	# external name
+	.long	0x6e	# DIE offset
+	.ascii "C\0"	# external name
+	.long	0x0
+	.section	.debug_str,"MS",@progbits,1
+.LASF5:
+	.string	"fp_t"
+.LASF2:
+	.string	"GNU C++ 4.4.2 20091222 (Red Hat 4.4.2-20)"
+.LASF0:
+	.string	"__pfn"
+.LASF4:
+	.string	"gdb/testsuite"
+.LASF3:
+	.string	"gdb.dwarf2/member-ptr-forwardref.cc"
+.LASF1:
+	.string	"__delta"
+	.ident	"GCC: (GNU) 4.4.2 20091222 (Red Hat 4.4.2-20)"
+	.section	.note.GNU-stack,"",@progbits
Index: testsuite/gdb.dwarf2/member-ptr-forwardref.exp
===================================================================
RCS file: testsuite/gdb.dwarf2/member-ptr-forwardref.exp
diff -N testsuite/gdb.dwarf2/member-ptr-forwardref.exp
--- /dev/null	1 Jan 1970 00:00:00 -0000
+++ testsuite/gdb.dwarf2/member-ptr-forwardref.exp	22 Jan 2010 17:01:08 -0000
@@ -0,0 +1,48 @@
+# Copyright 2010 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/>.
+
+# 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  
+}
+
+if { [skip_cplus_tests] } { continue }
+
+set testfile member-ptr-forwardref
+set executable ${testfile}
+set binfile ${objdir}/${subdir}/${executable}.x
+
+if { [gdb_compile "${srcdir}/${subdir}/${testfile}.S" ${binfile} object {debug}] != "" } {
+    untested ${testfile}.exp
+    return -1
+}
+
+gdb_exit
+gdb_start
+gdb_reinitialize_dir $srcdir/$subdir
+
+# Be sure to set cp-abi before ${binfile} gets loaded
+gdb_test "set cp-abi gnu-v3"
+gdb_test "show cp-abi" {The currently selected C\+\+ ABI is "gnu-v3".*}
+
+gdb_load ${binfile}
+
+gdb_test "ptype c" "type = class C {\[\r\n \t\]*int \\(C::\\*fp\\)\\(C \\*\\);\[\r\n \t\]*}"

Re: [patch] Fix crash on DWARF C++ forward reference

[Andreas Schwab]

Tom Tromey <tromey@redhat.com> writes:

> 2010-01-22  Jan Kratochvil  <jan.kratochvil@redhat.com>
>
> 	PR symtab/11199:
> 	* gdb.dwarf2/member-ptr-forwardref.exp,
> 	gdb.dwarf2/member-ptr-forwardref.S: New.

Running ./gdb.dwarf2/member-ptr-forwardref.exp ...
gdb compile failed, member-ptr-forwardref.cc: Assembler messages:
member-ptr-forwardref.cc:43: Error: unknown pseudo-op: `.bss'
member-ptr-forwardref.cc:60: Error: unknown pseudo-op: `.value'
member-ptr-forwardref.cc:295: Error: unknown pseudo-op: `.value'
member-ptr-forwardref.cc:305: Error: unknown pseudo-op: `.value'

Andreas.

-- 
Andreas Schwab, schwab@linux-m68k.org
GPG Key fingerprint = 58CA 54C7 6D53 942B 1756  01D3 44D5 214B 8276 4ED5
"And now for something completely different."

[obv] m68k fix of gdb.dwarf2/member-ptr-forwardref.S [Re: [patch] Fix crash on DWARF C++ forward reference]

[Jan Kratochvil]

On Fri, 19 Feb 2010 16:54:43 +0100, Andreas Schwab wrote:
> > 2010-01-22  Jan Kratochvil  <jan.kratochvil@redhat.com>
> >
> > 	PR symtab/11199:
> > 	* gdb.dwarf2/member-ptr-forwardref.exp,
> > 	gdb.dwarf2/member-ptr-forwardref.S: New.
> 
> Running ./gdb.dwarf2/member-ptr-forwardref.exp ...
> gdb compile failed, member-ptr-forwardref.cc: Assembler messages:
> member-ptr-forwardref.cc:43: Error: unknown pseudo-op: `.bss'
> member-ptr-forwardref.cc:60: Error: unknown pseudo-op: `.value'
> member-ptr-forwardref.cc:295: Error: unknown pseudo-op: `.value'
> member-ptr-forwardref.cc:305: Error: unknown pseudo-op: `.value'

Tested by m68k-unknown-linux-gnu gas and checked-in:


Thanks,
Jan


http://sourceware.org/ml/gdb-cvs/2010-02/msg00165.html

--- src/gdb/testsuite/ChangeLog	2010/02/19 17:13:21	1.2148
+++ src/gdb/testsuite/ChangeLog	2010/02/19 19:14:17	1.2149
@@ -1,3 +1,9 @@
+2010-02-19  Jan Kratochvil  <jan.kratochvil@redhat.com>
+
+	Fix compatibility with m68k as.
+	* gdb.dwarf2/member-ptr-forwardref.S: Use .data section.  Use .2byte.
+	Use only /* comments */.
+
 2010-02-18  Ulrich Weigand  <Ulrich.Weigand@de.ibm.com>
 
 	* configure.ac: Add gdb.multi/Makefile to AC_OUTPUT.
--- src/gdb/testsuite/gdb.dwarf2/member-ptr-forwardref.S	2010/01/22 17:06:49	1.1
+++ src/gdb/testsuite/gdb.dwarf2/member-ptr-forwardref.S	2010/02/19 19:14:18	1.2
@@ -40,7 +40,7 @@
 	.text
 .Ltext0:
 .globl fp
-	.bss
+	.data
 	.align 4
 	.type	fp, @object
 	.size	fp, 8
@@ -56,259 +56,259 @@
 .Letext0:
 	.file 1 "gdb.dwarf2/member-ptr-forwardref.cc"
 	.section	.debug_info
-	.long	0xa9	# Length of Compilation Unit Info
-	.value	0x3	# DWARF version number
-	.long	.Ldebug_abbrev0	# Offset Into Abbrev. Section
-	.byte	0x4	# Pointer Size (in bytes)
-	.uleb128 0x1	# (DIE (0xb) DW_TAG_compile_unit)
-	.long	.LASF2	# DW_AT_producer: "GNU C++ 4.4.2 20091222 (Red Hat 4.4.2-20)"
-	.byte	0x4	# DW_AT_language
-	.long	.LASF3	# DW_AT_name: "gdb.dwarf2/member-ptr-forwardref.cc"
-	.long	.LASF4	# DW_AT_comp_dir: "gdb/testsuite"
-	.long	.Ltext0	# DW_AT_low_pc
-	.long	.Letext0	# DW_AT_high_pc
-	.long	.Ldebug_line0	# DW_AT_stmt_list
-	.uleb128 0x2	# (DIE (0x25) DW_TAG_typedef)
-	.long	.LASF5	# DW_AT_name: "fp_t"
-	.byte	0x1	# DW_AT_decl_file (gdb.dwarf2/member-ptr-forwardref.cc)
-	.byte	0x13	# DW_AT_decl_line
-	.long	0x30	# DW_AT_type
-	.uleb128 0x3	# (DIE (0x30) DW_TAG_structure_type)
-	.byte	0x8	# DW_AT_byte_size
-	.byte	0x1	# DW_AT_decl_file (gdb.dwarf2/member-ptr-forwardref.cc)
-	.byte	0x13	# DW_AT_decl_line
-	.long	0x51	# DW_AT_sibling
-	.uleb128 0x4	# (DIE (0x38) DW_TAG_member)
-	.long	.LASF0	# DW_AT_name: "__pfn"
-	.byte	0x1	# DW_AT_decl_file (gdb.dwarf2/member-ptr-forwardref.cc)
-	.byte	0x13	# DW_AT_decl_line
-	.long	0x85	# DW_AT_type
-	.sleb128 0	# DW_AT_data_member_location
-	.uleb128 0x4	# (DIE (0x44) DW_TAG_member)
-	.long	.LASF1	# DW_AT_name: "__delta"
-	.byte	0x1	# DW_AT_decl_file (gdb.dwarf2/member-ptr-forwardref.cc)
-	.byte	0x13	# DW_AT_decl_line
-	.long	0x61	# DW_AT_type
-	.sleb128 4	# DW_AT_data_member_location
-	.byte	0x0	# end of children of DIE 0x30
-	.uleb128 0x5	# (DIE (0x51) DW_TAG_subroutine_type)
-	.long	0x61	# DW_AT_type
-	.long	0x61	# DW_AT_sibling
-	.uleb128 0x6	# (DIE (0x5a) DW_TAG_formal_parameter)
-	.long	0x68	# DW_AT_type
-	.byte	0x1	# DW_AT_artificial
-	.byte	0x0	# end of children of DIE 0x51
-	.uleb128 0x7	# (DIE (0x61) DW_TAG_base_type)
-	.byte	0x4	# DW_AT_byte_size
-	.byte	0x5	# DW_AT_encoding
-	.ascii "int\0"	# DW_AT_name
-	.uleb128 0x8	# (DIE (0x68) DW_TAG_pointer_type)
-	.byte	0x4	# DW_AT_byte_size
-	.long	0x6e	# DW_AT_type
-	.uleb128 0x9	# (DIE (0x6e) DW_TAG_structure_type)
-	.ascii "C\0"	# DW_AT_name
-	.byte	0x8	# DW_AT_byte_size
-	.byte	0x1	# DW_AT_decl_file (gdb.dwarf2/member-ptr-forwardref.cc)
-	.byte	0x16	# DW_AT_decl_line
-	.long	0x85	# DW_AT_sibling
-	.uleb128 0xa	# (DIE (0x78) DW_TAG_member)
-	.ascii "fp\0"	# DW_AT_name
-	.byte	0x1	# DW_AT_decl_file (gdb.dwarf2/member-ptr-forwardref.cc)
-	.byte	0x17	# DW_AT_decl_line
-	.long	0x30	# DW_AT_type
-	.sleb128 0	# DW_AT_data_member_location
-	.byte	0x3	# DW_AT_accessibility
-	.byte	0x0	# end of children of DIE 0x6e
-	.uleb128 0x8	# (DIE (0x85) DW_TAG_pointer_type)
-	.byte	0x4	# DW_AT_byte_size
-	.long	0x51	# DW_AT_type
-	.uleb128 0xb	# (DIE (0x8b) DW_TAG_variable)
-	.ascii "fp\0"	# DW_AT_name
-	.byte	0x1	# DW_AT_decl_file (gdb.dwarf2/member-ptr-forwardref.cc)
-	.byte	0x14	# DW_AT_decl_line
-	.long	0x25	# DW_AT_type
-	.byte	0x1	# DW_AT_external
-	.byte	0x5	# DW_AT_location
-	.byte	0x3	# DW_OP_addr
+	.long	0xa9	/* Length of Compilation Unit Info */
+	.2byte	0x3	/* DWARF version number */
+	.long	.Ldebug_abbrev0	/* Offset Into Abbrev. Section */
+	.byte	0x4	/* Pointer Size (in bytes) */
+	.uleb128 0x1	/* (DIE (0xb) DW_TAG_compile_unit) */
+	.long	.LASF2	/* DW_AT_producer: "GNU C++ 4.4.2 20091222 (Red Hat 4.4.2-20)" */
+	.byte	0x4	/* DW_AT_language */
+	.long	.LASF3	/* DW_AT_name: "gdb.dwarf2/member-ptr-forwardref.cc" */
+	.long	.LASF4	/* DW_AT_comp_dir: "gdb/testsuite" */
+	.long	.Ltext0	/* DW_AT_low_pc */
+	.long	.Letext0	/* DW_AT_high_pc */
+	.long	.Ldebug_line0	/* DW_AT_stmt_list */
+	.uleb128 0x2	/* (DIE (0x25) DW_TAG_typedef) */
+	.long	.LASF5	/* DW_AT_name: "fp_t" */
+	.byte	0x1	/* DW_AT_decl_file (gdb.dwarf2/member-ptr-forwardref.cc) */
+	.byte	0x13	/* DW_AT_decl_line */
+	.long	0x30	/* DW_AT_type */
+	.uleb128 0x3	/* (DIE (0x30) DW_TAG_structure_type) */
+	.byte	0x8	/* DW_AT_byte_size */
+	.byte	0x1	/* DW_AT_decl_file (gdb.dwarf2/member-ptr-forwardref.cc) */
+	.byte	0x13	/* DW_AT_decl_line */
+	.long	0x51	/* DW_AT_sibling */
+	.uleb128 0x4	/* (DIE (0x38) DW_TAG_member) */
+	.long	.LASF0	/* DW_AT_name: "__pfn" */
+	.byte	0x1	/* DW_AT_decl_file (gdb.dwarf2/member-ptr-forwardref.cc) */
+	.byte	0x13	/* DW_AT_decl_line */
+	.long	0x85	/* DW_AT_type */
+	.sleb128 0	/* DW_AT_data_member_location */
+	.uleb128 0x4	/* (DIE (0x44) DW_TAG_member) */
+	.long	.LASF1	/* DW_AT_name: "__delta" */
+	.byte	0x1	/* DW_AT_decl_file (gdb.dwarf2/member-ptr-forwardref.cc) */
+	.byte	0x13	/* DW_AT_decl_line */
+	.long	0x61	/* DW_AT_type */
+	.sleb128 4	/* DW_AT_data_member_location */
+	.byte	0x0	/* end of children of DIE 0x30 */
+	.uleb128 0x5	/* (DIE (0x51) DW_TAG_subroutine_type) */
+	.long	0x61	/* DW_AT_type */
+	.long	0x61	/* DW_AT_sibling */
+	.uleb128 0x6	/* (DIE (0x5a) DW_TAG_formal_parameter) */
+	.long	0x68	/* DW_AT_type */
+	.byte	0x1	/* DW_AT_artificial */
+	.byte	0x0	/* end of children of DIE 0x51 */
+	.uleb128 0x7	/* (DIE (0x61) DW_TAG_base_type) */
+	.byte	0x4	/* DW_AT_byte_size */
+	.byte	0x5	/* DW_AT_encoding */
+	.ascii "int\0"	/* DW_AT_name */
+	.uleb128 0x8	/* (DIE (0x68) DW_TAG_pointer_type) */
+	.byte	0x4	/* DW_AT_byte_size */
+	.long	0x6e	/* DW_AT_type */
+	.uleb128 0x9	/* (DIE (0x6e) DW_TAG_structure_type) */
+	.ascii "C\0"	/* DW_AT_name */
+	.byte	0x8	/* DW_AT_byte_size */
+	.byte	0x1	/* DW_AT_decl_file (gdb.dwarf2/member-ptr-forwardref.cc) */
+	.byte	0x16	/* DW_AT_decl_line */
+	.long	0x85	/* DW_AT_sibling */
+	.uleb128 0xa	/* (DIE (0x78) DW_TAG_member) */
+	.ascii "fp\0"	/* DW_AT_name */
+	.byte	0x1	/* DW_AT_decl_file (gdb.dwarf2/member-ptr-forwardref.cc) */
+	.byte	0x17	/* DW_AT_decl_line */
+	.long	0x30	/* DW_AT_type */
+	.sleb128 0	/* DW_AT_data_member_location */
+	.byte	0x3	/* DW_AT_accessibility */
+	.byte	0x0	/* end of children of DIE 0x6e */
+	.uleb128 0x8	/* (DIE (0x85) DW_TAG_pointer_type) */
+	.byte	0x4	/* DW_AT_byte_size */
+	.long	0x51	/* DW_AT_type */
+	.uleb128 0xb	/* (DIE (0x8b) DW_TAG_variable) */
+	.ascii "fp\0"	/* DW_AT_name */
+	.byte	0x1	/* DW_AT_decl_file (gdb.dwarf2/member-ptr-forwardref.cc) */
+	.byte	0x14	/* DW_AT_decl_line */
+	.long	0x25	/* DW_AT_type */
+	.byte	0x1	/* DW_AT_external */
+	.byte	0x5	/* DW_AT_location */
+	.byte	0x3	/* DW_OP_addr */
 	.long	fp
-	.uleb128 0xb	# (DIE (0x9c) DW_TAG_variable)
-	.ascii "c\0"	# DW_AT_name
-	.byte	0x1	# DW_AT_decl_file (gdb.dwarf2/member-ptr-forwardref.cc)
-	.byte	0x18	# DW_AT_decl_line
-	.long	0x6e	# DW_AT_type
-	.byte	0x1	# DW_AT_external
-	.byte	0x5	# DW_AT_location
-	.byte	0x3	# DW_OP_addr
+	.uleb128 0xb	/* (DIE (0x9c) DW_TAG_variable) */
+	.ascii "c\0"	/* DW_AT_name */
+	.byte	0x1	/* DW_AT_decl_file (gdb.dwarf2/member-ptr-forwardref.cc) */
+	.byte	0x18	/* DW_AT_decl_line */
+	.long	0x6e	/* DW_AT_type */
+	.byte	0x1	/* DW_AT_external */
+	.byte	0x5	/* DW_AT_location */
+	.byte	0x3	/* DW_OP_addr */
 	.long	c
-	.byte	0x0	# end of children of DIE 0xb
+	.byte	0x0	/* end of children of DIE 0xb */
 	.section	.debug_abbrev
-	.uleb128 0x1	# (abbrev code)
-	.uleb128 0x11	# (TAG: DW_TAG_compile_unit)
-	.byte	0x1	# DW_children_yes
-	.uleb128 0x25	# (DW_AT_producer)
-	.uleb128 0xe	# (DW_FORM_strp)
-	.uleb128 0x13	# (DW_AT_language)
-	.uleb128 0xb	# (DW_FORM_data1)
-	.uleb128 0x3	# (DW_AT_name)
-	.uleb128 0xe	# (DW_FORM_strp)
-	.uleb128 0x1b	# (DW_AT_comp_dir)
-	.uleb128 0xe	# (DW_FORM_strp)
-	.uleb128 0x11	# (DW_AT_low_pc)
-	.uleb128 0x1	# (DW_FORM_addr)
-	.uleb128 0x12	# (DW_AT_high_pc)
-	.uleb128 0x1	# (DW_FORM_addr)
-	.uleb128 0x10	# (DW_AT_stmt_list)
-	.uleb128 0x6	# (DW_FORM_data4)
-	.byte	0x0
-	.byte	0x0
-	.uleb128 0x2	# (abbrev code)
-	.uleb128 0x16	# (TAG: DW_TAG_typedef)
-	.byte	0x0	# DW_children_no
-	.uleb128 0x3	# (DW_AT_name)
-	.uleb128 0xe	# (DW_FORM_strp)
-	.uleb128 0x3a	# (DW_AT_decl_file)
-	.uleb128 0xb	# (DW_FORM_data1)
-	.uleb128 0x3b	# (DW_AT_decl_line)
-	.uleb128 0xb	# (DW_FORM_data1)
-	.uleb128 0x49	# (DW_AT_type)
-	.uleb128 0x13	# (DW_FORM_ref4)
-	.byte	0x0
-	.byte	0x0
-	.uleb128 0x3	# (abbrev code)
-	.uleb128 0x13	# (TAG: DW_TAG_structure_type)
-	.byte	0x1	# DW_children_yes
-	.uleb128 0xb	# (DW_AT_byte_size)
-	.uleb128 0xb	# (DW_FORM_data1)
-	.uleb128 0x3a	# (DW_AT_decl_file)
-	.uleb128 0xb	# (DW_FORM_data1)
-	.uleb128 0x3b	# (DW_AT_decl_line)
-	.uleb128 0xb	# (DW_FORM_data1)
-	.uleb128 0x1	# (DW_AT_sibling)
-	.uleb128 0x13	# (DW_FORM_ref4)
-	.byte	0x0
-	.byte	0x0
-	.uleb128 0x4	# (abbrev code)
-	.uleb128 0xd	# (TAG: DW_TAG_member)
-	.byte	0x0	# DW_children_no
-	.uleb128 0x3	# (DW_AT_name)
-	.uleb128 0xe	# (DW_FORM_strp)
-	.uleb128 0x3a	# (DW_AT_decl_file)
-	.uleb128 0xb	# (DW_FORM_data1)
-	.uleb128 0x3b	# (DW_AT_decl_line)
-	.uleb128 0xb	# (DW_FORM_data1)
-	.uleb128 0x49	# (DW_AT_type)
-	.uleb128 0x13	# (DW_FORM_ref4)
-	.uleb128 0x38	# (DW_AT_data_member_location)
-	.uleb128 0xd	# (DW_FORM_sdata)
-	.byte	0x0
-	.byte	0x0
-	.uleb128 0x5	# (abbrev code)
-	.uleb128 0x15	# (TAG: DW_TAG_subroutine_type)
-	.byte	0x1	# DW_children_yes
-	.uleb128 0x49	# (DW_AT_type)
-	.uleb128 0x13	# (DW_FORM_ref4)
-	.uleb128 0x1	# (DW_AT_sibling)
-	.uleb128 0x13	# (DW_FORM_ref4)
-	.byte	0x0
-	.byte	0x0
-	.uleb128 0x6	# (abbrev code)
-	.uleb128 0x5	# (TAG: DW_TAG_formal_parameter)
-	.byte	0x0	# DW_children_no
-	.uleb128 0x49	# (DW_AT_type)
-	.uleb128 0x13	# (DW_FORM_ref4)
-	.uleb128 0x34	# (DW_AT_artificial)
-	.uleb128 0xc	# (DW_FORM_flag)
-	.byte	0x0
-	.byte	0x0
-	.uleb128 0x7	# (abbrev code)
-	.uleb128 0x24	# (TAG: DW_TAG_base_type)
-	.byte	0x0	# DW_children_no
-	.uleb128 0xb	# (DW_AT_byte_size)
-	.uleb128 0xb	# (DW_FORM_data1)
-	.uleb128 0x3e	# (DW_AT_encoding)
-	.uleb128 0xb	# (DW_FORM_data1)
-	.uleb128 0x3	# (DW_AT_name)
-	.uleb128 0x8	# (DW_FORM_string)
-	.byte	0x0
-	.byte	0x0
-	.uleb128 0x8	# (abbrev code)
-	.uleb128 0xf	# (TAG: DW_TAG_pointer_type)
-	.byte	0x0	# DW_children_no
-	.uleb128 0xb	# (DW_AT_byte_size)
-	.uleb128 0xb	# (DW_FORM_data1)
-	.uleb128 0x49	# (DW_AT_type)
-	.uleb128 0x13	# (DW_FORM_ref4)
-	.byte	0x0
-	.byte	0x0
-	.uleb128 0x9	# (abbrev code)
-	.uleb128 0x13	# (TAG: DW_TAG_structure_type)
-	.byte	0x1	# DW_children_yes
-	.uleb128 0x3	# (DW_AT_name)
-	.uleb128 0x8	# (DW_FORM_string)
-	.uleb128 0xb	# (DW_AT_byte_size)
-	.uleb128 0xb	# (DW_FORM_data1)
-	.uleb128 0x3a	# (DW_AT_decl_file)
-	.uleb128 0xb	# (DW_FORM_data1)
-	.uleb128 0x3b	# (DW_AT_decl_line)
-	.uleb128 0xb	# (DW_FORM_data1)
-	.uleb128 0x1	# (DW_AT_sibling)
-	.uleb128 0x13	# (DW_FORM_ref4)
-	.byte	0x0
-	.byte	0x0
-	.uleb128 0xa	# (abbrev code)
-	.uleb128 0xd	# (TAG: DW_TAG_member)
-	.byte	0x0	# DW_children_no
-	.uleb128 0x3	# (DW_AT_name)
-	.uleb128 0x8	# (DW_FORM_string)
-	.uleb128 0x3a	# (DW_AT_decl_file)
-	.uleb128 0xb	# (DW_FORM_data1)
-	.uleb128 0x3b	# (DW_AT_decl_line)
-	.uleb128 0xb	# (DW_FORM_data1)
-	.uleb128 0x49	# (DW_AT_type)
-	.uleb128 0x13	# (DW_FORM_ref4)
-	.uleb128 0x38	# (DW_AT_data_member_location)
-	.uleb128 0xd	# (DW_FORM_sdata)
-	.uleb128 0x32	# (DW_AT_accessibility)
-	.uleb128 0xb	# (DW_FORM_data1)
-	.byte	0x0
-	.byte	0x0
-	.uleb128 0xb	# (abbrev code)
-	.uleb128 0x34	# (TAG: DW_TAG_variable)
-	.byte	0x0	# DW_children_no
-	.uleb128 0x3	# (DW_AT_name)
-	.uleb128 0x8	# (DW_FORM_string)
-	.uleb128 0x3a	# (DW_AT_decl_file)
-	.uleb128 0xb	# (DW_FORM_data1)
-	.uleb128 0x3b	# (DW_AT_decl_line)
-	.uleb128 0xb	# (DW_FORM_data1)
-	.uleb128 0x49	# (DW_AT_type)
-	.uleb128 0x13	# (DW_FORM_ref4)
-	.uleb128 0x3f	# (DW_AT_external)
-	.uleb128 0xc	# (DW_FORM_flag)
-	.uleb128 0x2	# (DW_AT_location)
-	.uleb128 0xa	# (DW_FORM_block1)
+	.uleb128 0x1	/* (abbrev code) */
+	.uleb128 0x11	/* (TAG: DW_TAG_compile_unit) */
+	.byte	0x1	/* DW_children_yes */
+	.uleb128 0x25	/* (DW_AT_producer) */
+	.uleb128 0xe	/* (DW_FORM_strp) */
+	.uleb128 0x13	/* (DW_AT_language) */
+	.uleb128 0xb	/* (DW_FORM_data1) */
+	.uleb128 0x3	/* (DW_AT_name) */
+	.uleb128 0xe	/* (DW_FORM_strp) */
+	.uleb128 0x1b	/* (DW_AT_comp_dir) */
+	.uleb128 0xe	/* (DW_FORM_strp) */
+	.uleb128 0x11	/* (DW_AT_low_pc) */
+	.uleb128 0x1	/* (DW_FORM_addr) */
+	.uleb128 0x12	/* (DW_AT_high_pc) */
+	.uleb128 0x1	/* (DW_FORM_addr) */
+	.uleb128 0x10	/* (DW_AT_stmt_list) */
+	.uleb128 0x6	/* (DW_FORM_data4) */
+	.byte	0x0
+	.byte	0x0
+	.uleb128 0x2	/* (abbrev code) */
+	.uleb128 0x16	/* (TAG: DW_TAG_typedef) */
+	.byte	0x0	/* DW_children_no */
+	.uleb128 0x3	/* (DW_AT_name) */
+	.uleb128 0xe	/* (DW_FORM_strp) */
+	.uleb128 0x3a	/* (DW_AT_decl_file) */
+	.uleb128 0xb	/* (DW_FORM_data1) */
+	.uleb128 0x3b	/* (DW_AT_decl_line) */
+	.uleb128 0xb	/* (DW_FORM_data1) */
+	.uleb128 0x49	/* (DW_AT_type) */
+	.uleb128 0x13	/* (DW_FORM_ref4) */
+	.byte	0x0
+	.byte	0x0
+	.uleb128 0x3	/* (abbrev code) */
+	.uleb128 0x13	/* (TAG: DW_TAG_structure_type) */
+	.byte	0x1	/* DW_children_yes */
+	.uleb128 0xb	/* (DW_AT_byte_size) */
+	.uleb128 0xb	/* (DW_FORM_data1) */
+	.uleb128 0x3a	/* (DW_AT_decl_file) */
+	.uleb128 0xb	/* (DW_FORM_data1) */
+	.uleb128 0x3b	/* (DW_AT_decl_line) */
+	.uleb128 0xb	/* (DW_FORM_data1) */
+	.uleb128 0x1	/* (DW_AT_sibling) */
+	.uleb128 0x13	/* (DW_FORM_ref4) */
+	.byte	0x0
+	.byte	0x0
+	.uleb128 0x4	/* (abbrev code) */
+	.uleb128 0xd	/* (TAG: DW_TAG_member) */
+	.byte	0x0	/* DW_children_no */
+	.uleb128 0x3	/* (DW_AT_name) */
+	.uleb128 0xe	/* (DW_FORM_strp) */
+	.uleb128 0x3a	/* (DW_AT_decl_file) */
+	.uleb128 0xb	/* (DW_FORM_data1) */
+	.uleb128 0x3b	/* (DW_AT_decl_line) */
+	.uleb128 0xb	/* (DW_FORM_data1) */
+	.uleb128 0x49	/* (DW_AT_type) */
+	.uleb128 0x13	/* (DW_FORM_ref4) */
+	.uleb128 0x38	/* (DW_AT_data_member_location) */
+	.uleb128 0xd	/* (DW_FORM_sdata) */
+	.byte	0x0
+	.byte	0x0
+	.uleb128 0x5	/* (abbrev code) */
+	.uleb128 0x15	/* (TAG: DW_TAG_subroutine_type) */
+	.byte	0x1	/* DW_children_yes */
+	.uleb128 0x49	/* (DW_AT_type) */
+	.uleb128 0x13	/* (DW_FORM_ref4) */
+	.uleb128 0x1	/* (DW_AT_sibling) */
+	.uleb128 0x13	/* (DW_FORM_ref4) */
+	.byte	0x0
+	.byte	0x0
+	.uleb128 0x6	/* (abbrev code) */
+	.uleb128 0x5	/* (TAG: DW_TAG_formal_parameter) */
+	.byte	0x0	/* DW_children_no */
+	.uleb128 0x49	/* (DW_AT_type) */
+	.uleb128 0x13	/* (DW_FORM_ref4) */
+	.uleb128 0x34	/* (DW_AT_artificial) */
+	.uleb128 0xc	/* (DW_FORM_flag) */
+	.byte	0x0
+	.byte	0x0
+	.uleb128 0x7	/* (abbrev code) */
+	.uleb128 0x24	/* (TAG: DW_TAG_base_type) */
+	.byte	0x0	/* DW_children_no */
+	.uleb128 0xb	/* (DW_AT_byte_size) */
+	.uleb128 0xb	/* (DW_FORM_data1) */
+	.uleb128 0x3e	/* (DW_AT_encoding) */
+	.uleb128 0xb	/* (DW_FORM_data1) */
+	.uleb128 0x3	/* (DW_AT_name) */
+	.uleb128 0x8	/* (DW_FORM_string) */
+	.byte	0x0
+	.byte	0x0
+	.uleb128 0x8	/* (abbrev code) */
+	.uleb128 0xf	/* (TAG: DW_TAG_pointer_type) */
+	.byte	0x0	/* DW_children_no */
+	.uleb128 0xb	/* (DW_AT_byte_size) */
+	.uleb128 0xb	/* (DW_FORM_data1) */
+	.uleb128 0x49	/* (DW_AT_type) */
+	.uleb128 0x13	/* (DW_FORM_ref4) */
+	.byte	0x0
+	.byte	0x0
+	.uleb128 0x9	/* (abbrev code) */
+	.uleb128 0x13	/* (TAG: DW_TAG_structure_type) */
+	.byte	0x1	/* DW_children_yes */
+	.uleb128 0x3	/* (DW_AT_name) */
+	.uleb128 0x8	/* (DW_FORM_string) */
+	.uleb128 0xb	/* (DW_AT_byte_size) */
+	.uleb128 0xb	/* (DW_FORM_data1) */
+	.uleb128 0x3a	/* (DW_AT_decl_file) */
+	.uleb128 0xb	/* (DW_FORM_data1) */
+	.uleb128 0x3b	/* (DW_AT_decl_line) */
+	.uleb128 0xb	/* (DW_FORM_data1) */
+	.uleb128 0x1	/* (DW_AT_sibling) */
+	.uleb128 0x13	/* (DW_FORM_ref4) */
+	.byte	0x0
+	.byte	0x0
+	.uleb128 0xa	/* (abbrev code) */
+	.uleb128 0xd	/* (TAG: DW_TAG_member) */
+	.byte	0x0	/* DW_children_no */
+	.uleb128 0x3	/* (DW_AT_name) */
+	.uleb128 0x8	/* (DW_FORM_string) */
+	.uleb128 0x3a	/* (DW_AT_decl_file) */
+	.uleb128 0xb	/* (DW_FORM_data1) */
+	.uleb128 0x3b	/* (DW_AT_decl_line) */
+	.uleb128 0xb	/* (DW_FORM_data1) */
+	.uleb128 0x49	/* (DW_AT_type) */
+	.uleb128 0x13	/* (DW_FORM_ref4) */
+	.uleb128 0x38	/* (DW_AT_data_member_location) */
+	.uleb128 0xd	/* (DW_FORM_sdata) */
+	.uleb128 0x32	/* (DW_AT_accessibility) */
+	.uleb128 0xb	/* (DW_FORM_data1) */
+	.byte	0x0
+	.byte	0x0
+	.uleb128 0xb	/* (abbrev code) */
+	.uleb128 0x34	/* (TAG: DW_TAG_variable) */
+	.byte	0x0	/* DW_children_no */
+	.uleb128 0x3	/* (DW_AT_name) */
+	.uleb128 0x8	/* (DW_FORM_string) */
+	.uleb128 0x3a	/* (DW_AT_decl_file) */
+	.uleb128 0xb	/* (DW_FORM_data1) */
+	.uleb128 0x3b	/* (DW_AT_decl_line) */
+	.uleb128 0xb	/* (DW_FORM_data1) */
+	.uleb128 0x49	/* (DW_AT_type) */
+	.uleb128 0x13	/* (DW_FORM_ref4) */
+	.uleb128 0x3f	/* (DW_AT_external) */
+	.uleb128 0xc	/* (DW_FORM_flag) */
+	.uleb128 0x2	/* (DW_AT_location) */
+	.uleb128 0xa	/* (DW_FORM_block1) */
 	.byte	0x0
 	.byte	0x0
 	.byte	0x0
 	.section	.debug_pubnames,"",@progbits
-	.long	0x1b	# Length of Public Names Info
-	.value	0x2	# DWARF Version
-	.long	.Ldebug_info0	# Offset of Compilation Unit Info
-	.long	0xad	# Compilation Unit Length
-	.long	0x8b	# DIE offset
-	.ascii "fp\0"	# external name
-	.long	0x9c	# DIE offset
-	.ascii "c\0"	# external name
+	.long	0x1b	/* Length of Public Names Info */
+	.2byte	0x2	/* DWARF Version */
+	.long	.Ldebug_info0	/* Offset of Compilation Unit Info */
+	.long	0xad	/* Compilation Unit Length */
+	.long	0x8b	/* DIE offset */
+	.ascii "fp\0"	/* external name */
+	.long	0x9c	/* DIE offset */
+	.ascii "c\0"	/* external name */
 	.long	0x0
 	.section	.debug_pubtypes,"",@progbits
-	.long	0x1d	# Length of Public Type Names Info
-	.value	0x2	# DWARF Version
-	.long	.Ldebug_info0	# Offset of Compilation Unit Info
-	.long	0xad	# Compilation Unit Length
-	.long	0x25	# DIE offset
-	.ascii "fp_t\0"	# external name
-	.long	0x6e	# DIE offset
-	.ascii "C\0"	# external name
+	.long	0x1d	/* Length of Public Type Names Info */
+	.2byte	0x2	/* DWARF Version */
+	.long	.Ldebug_info0	/* Offset of Compilation Unit Info */
+	.long	0xad	/* Compilation Unit Length */
+	.long	0x25	/* DIE offset */
+	.ascii "fp_t\0"	/* external name */
+	.long	0x6e	/* DIE offset */
+	.ascii "C\0"	/* external name */
 	.long	0x0
 	.section	.debug_str,"MS",@progbits,1
 .LASF5: