[3/3] RFC - optional patch to restore DW_AT_data_member_location

[3/3] RFC - optional patch to restore DW_AT_data_member_location

[Tom Tromey]

This patch reimplements DW_AT_data_member_location for variables
appearing in a Fortran common block.

This attribute is not specified by DWARF.  It is apparently an old
approach used by gfortran prior to 2008; at least it appeared in

    http://gcc.gnu.org/bugzilla/show_bug.cgi?id=23057

This patch is based on the idea that such attributes are relatively
rare.  So, rather than implement complicated support for them, gdb just
rewrites them into an ordinary location expression that uses the common
block's location as a subroutine.

I've included a new test case, which I made by editing the assembly
output of gfortran by hand.

Built and regtested on x86-64 Fedora 16.

I consider this patch optional, because I think it is too much
complicated code in support of a marginal and obsolete feature.
However, I wrote it in case someone thinks that supporting 4 year old
versions of gfortran is important.

Tom

	* dwarf2read.c (mark_common_block_symbol_computed): New function.
	(read_common_block): Handle child DIEs with
	DW_AT_data_member_location.
	(new_symbol_full): Add special case for common blocks.

	* gdb.dwarf2/dw2-common-block.S: New file.
	* gdb.dwarf2/dw2-common-block.exp: New file.
---
 gdb/dwarf2read.c                              |  138 ++++-
 gdb/testsuite/gdb.dwarf2/dw2-common-block.S   |  840 +++++++++++++++++++++++++
 gdb/testsuite/gdb.dwarf2/dw2-common-block.exp |   50 ++
 3 files changed, 1024 insertions(+), 4 deletions(-)
 create mode 100644 gdb/testsuite/gdb.dwarf2/dw2-common-block.S
 create mode 100644 gdb/testsuite/gdb.dwarf2/dw2-common-block.exp

diff --git a/gdb/dwarf2read.c b/gdb/dwarf2read.c
index ca827eb..925cc18 100644
--- a/gdb/dwarf2read.c
+++ b/gdb/dwarf2read.c
@@ -11060,6 +11060,71 @@ read_set_type (struct die_info *die, struct dwarf2_cu *cu)
   return set_die_type (die, set_type, cu);
 }
 
+/* A helper for read_common_block that creates a locexpr baton.  */
+
+static void
+mark_common_block_symbol_computed (struct symbol *sym,
+				   struct die_info *common_die,
+				   struct attribute *common_loc,
+				   struct attribute *member_loc,
+				   struct dwarf2_cu *cu)
+{
+  struct objfile *objfile = dwarf2_per_objfile->objfile;
+  struct dwarf2_locexpr_baton *baton;
+  gdb_byte *ptr;
+  unsigned int cu_off;
+  enum bfd_endian byte_order = gdbarch_byte_order (get_objfile_arch (objfile));
+  LONGEST offset;
+
+  gdb_assert (common_loc && member_loc);
+  gdb_assert (attr_form_is_block (common_loc));
+  gdb_assert (attr_form_is_block (member_loc)
+	      || attr_form_is_constant (member_loc));
+
+  baton = obstack_alloc (&objfile->objfile_obstack,
+			 sizeof (struct dwarf2_locexpr_baton));
+  baton->per_cu = cu->per_cu;
+  gdb_assert (baton->per_cu);
+
+  baton->size = 5 /* DW_OP_call4 */ + 1 /* DW_OP_plus */;
+
+  if (attr_form_is_constant (member_loc))
+    {
+      offset = dwarf2_get_attr_constant_value (member_loc, 0);
+      baton->size += 1 /* DW_OP_addr */ + cu->header.addr_size;
+    }
+  else
+    baton->size += DW_BLOCK (member_loc)->size;
+
+  ptr = obstack_alloc (&objfile->objfile_obstack, baton->size);
+  baton->data = ptr;
+
+  *ptr++ = DW_OP_call4;
+  cu_off = common_die->offset.sect_off - cu->per_cu->offset.sect_off;
+  store_unsigned_integer (ptr, 4, byte_order, cu_off);
+  ptr += 4;
+
+  if (attr_form_is_constant (member_loc))
+    {
+      *ptr++ = DW_OP_addr;
+      store_unsigned_integer (ptr, cu->header.addr_size, byte_order, offset);
+      ptr += cu->header.addr_size;
+    }
+  else
+    {
+      /* We have to copy the data here, because DW_OP_call4 will only
+	 use a DW_AT_location attribute.  */
+      memcpy (ptr, DW_BLOCK (member_loc)->data, DW_BLOCK (member_loc)->size);
+      ptr += DW_BLOCK (member_loc)->size;
+    }
+
+  *ptr = DW_OP_plus;
+
+  SYMBOL_COMPUTED_OPS (sym) = &dwarf2_locexpr_funcs;
+  SYMBOL_LOCATION_BATON (sym) = baton;
+  SYMBOL_CLASS (sym) = LOC_COMPUTED;
+}
+
 /* Create appropriate locally-scoped variables for all the
    DW_TAG_common_block entries.  Also create a struct
    fortran_common_block listing all such variables for `info common'.
@@ -11069,6 +11134,29 @@ read_set_type (struct die_info *die, struct dwarf2_cu *cu)
 static void
 read_common_block (struct die_info *die, struct dwarf2_cu *cu)
 {
+  struct attribute *attr;
+
+  attr = dwarf2_attr (die, DW_AT_location, cu);
+  if (attr)
+    {
+      /* Support the .debug_loc offsets.  */
+      if (attr_form_is_block (attr))
+        {
+	  /* Ok.  */
+        }
+      else if (attr_form_is_section_offset (attr))
+        {
+	  dwarf2_complex_location_expr_complaint ();
+	  attr = NULL;
+        }
+      else
+        {
+	  dwarf2_invalid_attrib_class_complaint ("DW_AT_location",
+						 "common block member");
+	  attr = NULL;
+        }
+    }
+
   if (die->child != NULL)
     {
       struct objfile *objfile = cu->objfile;
@@ -11097,8 +11185,39 @@ read_common_block (struct die_info *die, struct dwarf2_cu *cu)
 	  /* Create the symbol in the DW_TAG_common_block block in the current
 	     symbol scope.  */
 	  sym = new_symbol (child_die, NULL, cu);
-	  if (sym)
-	    common_block->contents[count++] = sym;
+	  if (sym != NULL)
+	    {
+	      struct attribute *member_loc;
+
+	      common_block->contents[count++] = sym;
+
+	      member_loc = dwarf2_attr (child_die, DW_AT_data_member_location,
+					cu);
+	      if (member_loc)
+		{
+		  /* GDB has handled this for a long time, but it is
+		     not specified by DWARF.  It seems to have been
+		     emitted by gfortran at least as recently as:
+		     http://gcc.gnu.org/bugzilla/show_bug.cgi?id=23057.  */
+		  complaint (&symfile_complaints,
+			     _("Variable in common block has "
+			       "DW_AT_data_member_location "
+			       "- DIE at 0x%x [in module %s]"),
+			     child_die->offset.sect_off, cu->objfile->name);
+
+		  if (attr_form_is_section_offset (member_loc))
+		    dwarf2_complex_location_expr_complaint ();
+		  else if (attr_form_is_constant (member_loc)
+			   || attr_form_is_block (member_loc))
+		    {
+		      if (attr)
+			mark_common_block_symbol_computed (sym, die, attr,
+							   member_loc, cu);
+		    }
+		  else
+		    dwarf2_complex_location_expr_complaint ();
+		}
+	    }
 	}
 
       sym = new_symbol (die, objfile_type (objfile)->builtin_void, cu);
@@ -14998,8 +15117,19 @@ new_symbol_full (struct die_info *die, struct type *type, struct dwarf2_cu *cu,
 	         the minimal symbol table whenever the variable is
 	         referenced.  */
 	      attr2 = dwarf2_attr (die, DW_AT_external, cu);
-	      if (attr2 && (DW_UNSND (attr2) != 0)
-		  && dwarf2_attr (die, DW_AT_type, cu) != NULL)
+
+	      /* Fortran explicitly imports any global symbols to the local
+		 scope by DW_TAG_common_block.  */
+	      if (cu->language == language_fortran && die->parent
+		  && die->parent->tag == DW_TAG_common_block)
+		{
+		  /* SYMBOL_CLASS doesn't matter here because
+		     read_common_block is going to reset it.  */
+		  if (!suppress_add)
+		    list_to_add = cu->list_in_scope;
+		}
+	      else if (attr2 && (DW_UNSND (attr2) != 0)
+		       && dwarf2_attr (die, DW_AT_type, cu) != NULL)
 		{
 		  /* A variable with DW_AT_external is never static, but it
 		     may be block-scoped.  */
diff --git a/gdb/testsuite/gdb.dwarf2/dw2-common-block.S b/gdb/testsuite/gdb.dwarf2/dw2-common-block.S
new file mode 100644
index 0000000..e4b6262
--- /dev/null
+++ b/gdb/testsuite/gdb.dwarf2/dw2-common-block.S
@@ -0,0 +1,840 @@
+/* This testcase is part of GDB, the GNU debugger.
+
+   Copyright 2012 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 was made from ../gdb.fortran/common-block.f90 using
+	gfortran -dA -S -g
+   and then hand-editing the assembly a bit to introduce
+   DW_AT_data_member_location.  */
+
+	.file	"common-block.f90"
+	.text
+.Ltext0:
+	.globl	in_
+	.type	in_, @function
+in_:
+.LFB0:
+	.file 1 "../gdb.fortran/common-block.f90"
+	# ../gdb.fortran/common-block.f90:21
+	.loc 1 21 0
+	.cfi_startproc
+	# basic block 2
+	pushq	%rbp
+	.cfi_def_cfa_offset 16
+	.cfi_offset 6, -16
+	movq	%rsp, %rbp
+	.cfi_def_cfa_register 6
+	subq	$16, %rsp
+	# ../gdb.fortran/common-block.f90:34
+	.loc 1 34 0
+	movl	$5, -4(%rbp)
+	# ../gdb.fortran/common-block.f90:35
+	.loc 1 35 0
+	movl	$55, -8(%rbp)
+	# ../gdb.fortran/common-block.f90:21
+	.loc 1 21 0
+	movl	fo_o_(%rip), %eax
+	# ../gdb.fortran/common-block.f90:37
+	.loc 1 37 0
+	cmpl	$11, %eax
+	jne	.L2
+	# basic block 3
+	# ../gdb.fortran/common-block.f90:21
+	.loc 1 21 0 discriminator 2
+	movss	fo_o_+4(%rip), %xmm0
+	# ../gdb.fortran/common-block.f90:37
+	.loc 1 37 0 discriminator 2
+	ucomiss	.LC0(%rip), %xmm0
+	jp	.L2
+	# basic block 4
+	ucomiss	.LC0(%rip), %xmm0
+	jne	.L2
+	# basic block 5
+	# ../gdb.fortran/common-block.f90:21
+	.loc 1 21 0 discriminator 3
+	movsd	fo_o_+8(%rip), %xmm0
+	# ../gdb.fortran/common-block.f90:37
+	.loc 1 37 0 discriminator 3
+	ucomisd	.LC1(%rip), %xmm0
+	jp	.L2
+	# basic block 6
+	ucomisd	.LC1(%rip), %xmm0
+	je	.L8
+.L2:
+	# basic block 7
+	# ../gdb.fortran/common-block.f90:37
+	.loc 1 37 0 is_stmt 0 discriminator 1
+	movl	$0, %eax
+	call	_gfortran_abort
+.L8:
+	# basic block 8
+	# ../gdb.fortran/common-block.f90:21
+	.loc 1 21 0 is_stmt 1
+	movl	foo_(%rip), %eax
+	# ../gdb.fortran/common-block.f90:38
+	.loc 1 38 0
+	cmpl	$1, %eax
+	jne	.L5
+	# basic block 9
+	# ../gdb.fortran/common-block.f90:21
+	.loc 1 21 0 discriminator 2
+	movss	foo_+4(%rip), %xmm0
+	# ../gdb.fortran/common-block.f90:38
+	.loc 1 38 0 discriminator 2
+	ucomiss	.LC2(%rip), %xmm0
+	jp	.L5
+	# basic block 10
+	ucomiss	.LC2(%rip), %xmm0
+	jne	.L5
+	# basic block 11
+	# ../gdb.fortran/common-block.f90:21
+	.loc 1 21 0 discriminator 3
+	movsd	foo_+8(%rip), %xmm0
+	# ../gdb.fortran/common-block.f90:38
+	.loc 1 38 0 discriminator 3
+	ucomisd	.LC3(%rip), %xmm0
+	jp	.L5
+	# basic block 12
+	ucomisd	.LC3(%rip), %xmm0
+	je	.L9
+.L5:
+	# basic block 13
+	# ../gdb.fortran/common-block.f90:38
+	.loc 1 38 0 is_stmt 0 discriminator 1
+	movl	$0, %eax
+	call	_gfortran_abort
+.L9:
+	# basic block 14
+	# ../gdb.fortran/common-block.f90:40
+	.loc 1 40 0 is_stmt 1
+	movl	$0, fo_o_(%rip)
+	# ../gdb.fortran/common-block.f90:42
+	.loc 1 42 0
+	leave
+	.cfi_def_cfa 7, 8
+	ret
+	.cfi_endproc
+.LFE0:
+	.size	in_, .-in_
+	.type	MAIN__, @function
+MAIN__:
+.LFB1:
+	# ../gdb.fortran/common-block.f90:44
+	.loc 1 44 0
+	.cfi_startproc
+	# basic block 2
+	pushq	%rbp
+	.cfi_def_cfa_offset 16
+	.cfi_offset 6, -16
+	movq	%rsp, %rbp
+	.cfi_def_cfa_register 6
+	# ../gdb.fortran/common-block.f90:57
+	.loc 1 57 0
+	movl	$1, foo_(%rip)
+	# ../gdb.fortran/common-block.f90:58
+	.loc 1 58 0
+	movl	$0x40000000, %eax
+	movl	%eax, foo_+4(%rip)
+	# ../gdb.fortran/common-block.f90:59
+	.loc 1 59 0
+	movabsq	$4613937818241073152, %rax
+	movq	%rax, foo_+8(%rip)
+	# ../gdb.fortran/common-block.f90:61
+	.loc 1 61 0
+	movl	$11, fo_o_(%rip)
+	# ../gdb.fortran/common-block.f90:62
+	.loc 1 62 0
+	movl	$0x41b00000, %eax
+	movl	%eax, fo_o_+4(%rip)
+	# ../gdb.fortran/common-block.f90:63
+	.loc 1 63 0
+	movabsq	$4629841154425225216, %rax
+	movq	%rax, fo_o_+8(%rip)
+	# ../gdb.fortran/common-block.f90:65
+	.loc 1 65 0
+	movl	$0, %eax
+	call	in_
+	# ../gdb.fortran/common-block.f90:67
+	.loc 1 67 0
+	popq	%rbp
+	.cfi_def_cfa 7, 8
+	ret
+	.cfi_endproc
+.LFE1:
+	.size	MAIN__, .-MAIN__
+	.globl	main
+	.type	main, @function
+main:
+.LFB2:
+	# ../gdb.fortran/common-block.f90:67
+	.loc 1 67 0
+	.cfi_startproc
+	# basic block 2
+	pushq	%rbp
+	.cfi_def_cfa_offset 16
+	.cfi_offset 6, -16
+	movq	%rsp, %rbp
+	.cfi_def_cfa_register 6
+	subq	$16, %rsp
+	movl	%edi, -4(%rbp)
+	movq	%rsi, -16(%rbp)
+	# ../gdb.fortran/common-block.f90:67
+	.loc 1 67 0
+	movq	-16(%rbp), %rdx
+	movl	-4(%rbp), %eax
+	movq	%rdx, %rsi
+	movl	%eax, %edi
+	call	_gfortran_set_args
+	movl	$options.0.1570, %esi
+	movl	$8, %edi
+	call	_gfortran_set_options
+	call	MAIN__
+	movl	$0, %eax
+	leave
+	.cfi_def_cfa 7, 8
+	ret
+	.cfi_endproc
+.LFE2:
+	.size	main, .-main
+	.comm	foo_,16,16
+	.comm	fo_o_,16,16
+	.section	.rodata
+	.align 32
+	.type	options.0.1570, @object
+	.size	options.0.1570, 32
+options.0.1570:
+	.long	68
+	.long	511
+	.long	0
+	.long	0
+	.long	0
+	.long	1
+	.long	0
+	.long	1
+	.align 4
+.LC0:
+	.long	1102053376
+	.align 8
+.LC1:
+	.long	0
+	.long	1077968896
+	.align 4
+.LC2:
+	.long	1073741824
+	.align 8
+.LC3:
+	.long	0
+	.long	1074266112
+	.text
+.Letext0:
+	.section	.debug_info,"",@progbits
+.Ldebug_info0:
+	.long	.Ldebuginfo_end - .Ldebug_info1	# Length of Compilation Unit Info
+.Ldebug_info1:
+	.value	0x4	# DWARF version number
+	.long	.Ldebug_abbrev0	# Offset Into Abbrev. Section
+	.byte	0x8	# Pointer Size (in bytes)
+	.uleb128 0x1	# (DIE (0xb) DW_TAG_compile_unit)
+	.long	.LASF13	# DW_AT_producer: "GNU Fortran 4.6.3 20120306 (Red Hat 4.6.3-2) -mtune=generic -march=x86-64 -g -fintrinsic-modules-path /usr/lib/gcc/x86_64-redhat-linux/4.6.3/finclude"
+	.byte	0xe	# DW_AT_language
+	.byte	0x2	# DW_AT_identifier_case
+	.long	.LASF14	# DW_AT_name: "../gdb.fortran/common-block.f90"
+	.long	.LASF15	# DW_AT_comp_dir: "/home/tromey/gnu/archer/archer/gdb/testsuite/gdb.dwarf2"
+	.quad	.Ltext0	# DW_AT_low_pc
+	.quad	.Letext0	# DW_AT_high_pc
+	.long	.Ldebug_line0	# DW_AT_stmt_list
+	.uleb128 0x2	# (DIE (0x2e) DW_TAG_subprogram)
+			# DW_AT_external
+	.ascii "in\0"	# DW_AT_name
+	.byte	0x1	# DW_AT_decl_file (../gdb.fortran/common-block.f90)
+	.byte	0x15	# DW_AT_decl_line
+	.ascii "in_\0"	# DW_AT_linkage_name
+	.quad	.LFB0	# DW_AT_low_pc
+	.quad	.LFE0	# DW_AT_high_pc
+	.uleb128 0x1	# DW_AT_frame_base
+	.byte	0x9c	# DW_OP_call_frame_cfa
+			# DW_AT_GNU_all_tail_call_sites
+	.long	0x11a	# DW_AT_sibling
+	.uleb128 0x3	# (DIE (0x4e) DW_TAG_common_block)
+	.long	.LASF0	# DW_AT_name: "fo_o"
+	.byte	0x1	# DW_AT_decl_file (../gdb.fortran/common-block.f90)
+	.byte	0x1f	# DW_AT_decl_line
+	.long	.LASF8	# DW_AT_linkage_name: "fo_o_"
+	.uleb128 0x9	# DW_AT_location
+	.byte	0x3	# DW_OP_addr
+	.quad	fo_o_
+	.long	0xa5	# DW_AT_sibling
+	.uleb128 0x10	# (DIE (0x1bb) DW_TAG_variable)
+	.ascii "ix\0"	# DW_AT_name
+	.byte	0x1	# DW_AT_decl_file (../gdb.fortran/common-block.f90)
+	.byte	0x2e	# DW_AT_decl_line
+	.long	0x11a	# DW_AT_type
+			# DW_AT_external
+	.uleb128 0x9	# DW_AT_data_member_location
+			# (size chosen to avoid renumbering all DIEs)
+	.byte	0x8	# DW_OP_const1u
+	.byte	0x0
+	.byte	0x96	# DW_OP_nop
+	.byte	0x96	# DW_OP_nop
+	.byte	0x96	# DW_OP_nop
+	.byte	0x96	# DW_OP_nop
+	.byte	0x96	# DW_OP_nop
+	.byte	0x96	# DW_OP_nop
+	.byte	0x96	# DW_OP_nop
+	.uleb128 0x4	# (DIE (0x7b) DW_TAG_variable)
+	.ascii "iy2\0"	# DW_AT_name
+	.byte	0x1	# DW_AT_decl_file (../gdb.fortran/common-block.f90)
+	.byte	0x18	# DW_AT_decl_line
+	.long	0x121	# DW_AT_type
+			# DW_AT_external
+	.uleb128 0x9	# DW_AT_location
+	.byte	0x3	# DW_OP_addr
+	.quad	fo_o_+4
+	.uleb128 0x4	# (DIE (0x90) DW_TAG_variable)
+	.ascii "iz\0"	# DW_AT_name
+	.byte	0x1	# DW_AT_decl_file (../gdb.fortran/common-block.f90)
+	.byte	0x19	# DW_AT_decl_line
+	.long	0x128	# DW_AT_type
+			# DW_AT_external
+	.uleb128 0x9	# DW_AT_location
+	.byte	0x3	# DW_OP_addr
+	.quad	fo_o_+8
+	.byte	0	# end of children of DIE 0x4e
+	.uleb128 0x5	# (DIE (0xa5) DW_TAG_common_block)
+	.ascii "foo\0"	# DW_AT_name
+	.byte	0x1	# DW_AT_decl_file (../gdb.fortran/common-block.f90)
+	.byte	0x20	# DW_AT_decl_line
+	.long	.LASF16	# DW_AT_linkage_name: "foo_"
+	.uleb128 0x9	# DW_AT_location
+	.byte	0x3	# DW_OP_addr
+	.quad	foo_
+	.long	0xfe	# DW_AT_sibling
+	.uleb128 0x6	# (DIE (0xbe) DW_TAG_variable)
+	.long	.LASF1	# DW_AT_name: "ix_x"
+	.byte	0x1	# DW_AT_decl_file (../gdb.fortran/common-block.f90)
+	.byte	0x1b	# DW_AT_decl_line
+	.long	0x11a	# DW_AT_type
+			# DW_AT_external
+	.uleb128 0x9	# DW_AT_location
+	.byte	0x3	# DW_OP_addr
+	.quad	foo_
+	.uleb128 0x6	# (DIE (0xd3) DW_TAG_variable)
+	.long	.LASF2	# DW_AT_name: "iy_y"
+	.byte	0x1	# DW_AT_decl_file (../gdb.fortran/common-block.f90)
+	.byte	0x1c	# DW_AT_decl_line
+	.long	0x121	# DW_AT_type
+			# DW_AT_external
+	.uleb128 0x9	# DW_AT_location
+	.byte	0x3	# DW_OP_addr
+	.quad	foo_+4
+	.uleb128 0x6	# (DIE (0xe8) DW_TAG_variable)
+	.long	.LASF3	# DW_AT_name: "iz_z2"
+	.byte	0x1	# DW_AT_decl_file (../gdb.fortran/common-block.f90)
+	.byte	0x1d	# DW_AT_decl_line
+	.long	0x128	# DW_AT_type
+			# DW_AT_external
+	.uleb128 0x9	# DW_AT_location
+	.byte	0x3	# DW_OP_addr
+	.quad	foo_+8
+	.byte	0	# end of children of DIE 0xa5
+	.uleb128 0x7	# (DIE (0xfe) DW_TAG_variable)
+	.ascii "iy\0"	# DW_AT_name
+	.byte	0x1	# DW_AT_decl_file (../gdb.fortran/common-block.f90)
+	.byte	0x22	# DW_AT_decl_line
+	.long	0x11a	# DW_AT_type
+	.uleb128 0x2	# DW_AT_location
+	.byte	0x91	# DW_OP_fbreg
+	.sleb128 -20
+	.uleb128 0x8	# (DIE (0x10b) DW_TAG_variable)
+	.long	.LASF4	# DW_AT_name: "iz_z"
+	.byte	0x1	# DW_AT_decl_file (../gdb.fortran/common-block.f90)
+	.byte	0x23	# DW_AT_decl_line
+	.long	0x11a	# DW_AT_type
+	.uleb128 0x2	# DW_AT_location
+	.byte	0x91	# DW_OP_fbreg
+	.sleb128 -24
+	.byte	0	# end of children of DIE 0x2e
+	.uleb128 0x9	# (DIE (0x11a) DW_TAG_base_type)
+	.byte	0x4	# DW_AT_byte_size
+	.byte	0x5	# DW_AT_encoding
+	.long	.LASF5	# DW_AT_name: "integer(kind=4)"
+	.uleb128 0x9	# (DIE (0x121) DW_TAG_base_type)
+	.byte	0x4	# DW_AT_byte_size
+	.byte	0x4	# DW_AT_encoding
+	.long	.LASF6	# DW_AT_name: "real(kind=4)"
+	.uleb128 0x9	# (DIE (0x128) DW_TAG_base_type)
+	.byte	0x8	# DW_AT_byte_size
+	.byte	0x4	# DW_AT_encoding
+	.long	.LASF7	# DW_AT_name: "real(kind=8)"
+	.uleb128 0xa	# (DIE (0x12f) DW_TAG_subprogram)
+	.long	.LASF17	# DW_AT_name: "common_test"
+	.byte	0x1	# DW_AT_decl_file (../gdb.fortran/common-block.f90)
+	.byte	0x2c	# DW_AT_decl_line
+	.quad	.LFB1	# DW_AT_low_pc
+	.quad	.LFE1	# DW_AT_high_pc
+	.uleb128 0x1	# DW_AT_frame_base
+	.byte	0x9c	# DW_OP_call_frame_cfa
+			# DW_AT_GNU_all_tail_call_sites
+			# DW_AT_main_subprogram
+	.byte	0x2	# DW_AT_calling_convention
+	.long	0x1f9	# DW_AT_sibling
+	.uleb128 0x3	# (DIE (0x14d) DW_TAG_common_block)
+	.long	.LASF0	# DW_AT_name: "fo_o"
+	.byte	0x1	# DW_AT_decl_file (../gdb.fortran/common-block.f90)
+	.byte	0x1f	# DW_AT_decl_line
+	.long	.LASF8	# DW_AT_linkage_name: "fo_o_"
+	.uleb128 0x9	# DW_AT_location
+	.byte	0x3	# DW_OP_addr
+	.quad	fo_o_
+	.long	0x1a6	# DW_AT_sibling
+	.uleb128 0x6	# (DIE (0x166) DW_TAG_variable)
+	.long	.LASF1	# DW_AT_name: "ix_x"
+	.byte	0x1	# DW_AT_decl_file (../gdb.fortran/common-block.f90)
+	.byte	0x32	# DW_AT_decl_line
+	.long	0x11a	# DW_AT_type
+			# DW_AT_external
+	.uleb128 0x9	# DW_AT_location
+	.byte	0x3	# DW_OP_addr
+	.quad	fo_o_
+	.uleb128 0x6	# (DIE (0x17b) DW_TAG_variable)
+	.long	.LASF2	# DW_AT_name: "iy_y"
+	.byte	0x1	# DW_AT_decl_file (../gdb.fortran/common-block.f90)
+	.byte	0x33	# DW_AT_decl_line
+	.long	0x121	# DW_AT_type
+			# DW_AT_external
+	.uleb128 0x9	# DW_AT_location
+	.byte	0x3	# DW_OP_addr
+	.quad	fo_o_+4
+	.uleb128 0x6	# (DIE (0x190) DW_TAG_variable)
+	.long	.LASF4	# DW_AT_name: "iz_z"
+	.byte	0x1	# DW_AT_decl_file (../gdb.fortran/common-block.f90)
+	.byte	0x34	# DW_AT_decl_line
+	.long	0x128	# DW_AT_type
+			# DW_AT_external
+	.uleb128 0x9	# DW_AT_location
+	.byte	0x3	# DW_OP_addr
+	.quad	fo_o_+8
+	.byte	0	# end of children of DIE 0x14d
+	.uleb128 0xb	# (DIE (0x1a6) DW_TAG_common_block)
+	.ascii "foo\0"	# DW_AT_name
+	.byte	0x1	# DW_AT_decl_file (../gdb.fortran/common-block.f90)
+	.byte	0x20	# DW_AT_decl_line
+	.long	.LASF16	# DW_AT_linkage_name: "foo_"
+	.uleb128 0x9	# DW_AT_location
+	.byte	0x3	# DW_OP_addr
+	.quad	foo_
+	.uleb128 0x10	# (DIE (0x1bb) DW_TAG_variable)
+	.ascii "ix\0"	# DW_AT_name
+	.byte	0x1	# DW_AT_decl_file (../gdb.fortran/common-block.f90)
+	.byte	0x2e	# DW_AT_decl_line
+	.long	0x11a	# DW_AT_type
+			# DW_AT_external
+	.uleb128 0x9	# DW_AT_data_member_location
+			# (size chosen to avoid renumbering all DIEs)
+	.byte	0x8	# DW_OP_const1u
+	.byte	0x0
+	.byte	0x96	# DW_OP_nop
+	.byte	0x96	# DW_OP_nop
+	.byte	0x96	# DW_OP_nop
+	.byte	0x96	# DW_OP_nop
+	.byte	0x96	# DW_OP_nop
+	.byte	0x96	# DW_OP_nop
+	.byte	0x96	# DW_OP_nop
+	.uleb128 0x4	# (DIE (0x1cf) DW_TAG_variable)
+	.ascii "iy\0"	# DW_AT_name
+	.byte	0x1	# DW_AT_decl_file (../gdb.fortran/common-block.f90)
+	.byte	0x2f	# DW_AT_decl_line
+	.long	0x121	# DW_AT_type
+			# DW_AT_external
+	.uleb128 0x9	# DW_AT_location
+	.byte	0x3	# DW_OP_addr
+	.quad	foo_+4
+	.uleb128 0x4	# (DIE (0x1e3) DW_TAG_variable)
+	.ascii "iz\0"	# DW_AT_name
+	.byte	0x1	# DW_AT_decl_file (../gdb.fortran/common-block.f90)
+	.byte	0x30	# DW_AT_decl_line
+	.long	0x128	# DW_AT_type
+			# DW_AT_external
+	.uleb128 0x9	# DW_AT_location
+	.byte	0x3	# DW_OP_addr
+	.quad	foo_+8
+	.byte	0	# end of children of DIE 0x1a6
+	.byte	0	# end of children of DIE 0x12f
+	.uleb128 0xc	# (DIE (0x1f9) DW_TAG_subprogram)
+			# DW_AT_external
+	.long	.LASF9	# DW_AT_name: "main"
+	.byte	0x1	# DW_AT_decl_file (../gdb.fortran/common-block.f90)
+	.byte	0x43	# DW_AT_decl_line
+	.long	0x11a	# DW_AT_type
+	.quad	.LFB2	# DW_AT_low_pc
+	.quad	.LFE2	# DW_AT_high_pc
+	.uleb128 0x1	# DW_AT_frame_base
+	.byte	0x9c	# DW_OP_call_frame_cfa
+			# DW_AT_GNU_all_tail_call_sites
+	.long	0x238	# DW_AT_sibling
+	.uleb128 0xd	# (DIE (0x21a) DW_TAG_formal_parameter)
+	.long	.LASF10	# DW_AT_name: "argc"
+	.byte	0x1	# DW_AT_decl_file (../gdb.fortran/common-block.f90)
+	.byte	0x43	# DW_AT_decl_line
+	.long	0x238	# DW_AT_type
+	.uleb128 0x2	# DW_AT_location
+	.byte	0x91	# DW_OP_fbreg
+	.sleb128 -20
+	.uleb128 0xd	# (DIE (0x228) DW_TAG_formal_parameter)
+	.long	.LASF11	# DW_AT_name: "argv"
+	.byte	0x1	# DW_AT_decl_file (../gdb.fortran/common-block.f90)
+	.byte	0x43	# DW_AT_decl_line
+	.long	0x23d	# DW_AT_type
+	.uleb128 0x3	# DW_AT_location
+	.byte	0x91	# DW_OP_fbreg
+	.sleb128 -32
+	.byte	0x6	# DW_OP_deref
+	.byte	0	# end of children of DIE 0x1f9
+	.uleb128 0xe	# (DIE (0x238) DW_TAG_const_type)
+	.long	0x11a	# DW_AT_type
+	.uleb128 0xf	# (DIE (0x23d) DW_TAG_pointer_type)
+	.byte	0x8	# DW_AT_byte_size
+	.long	0x243	# DW_AT_type
+	.uleb128 0x9	# (DIE (0x243) DW_TAG_base_type)
+	.byte	0x1	# DW_AT_byte_size
+	.byte	0x8	# DW_AT_encoding
+	.long	.LASF12	# DW_AT_name: "character(kind=1)"
+	.byte	0	# end of children of DIE 0xb
+.Ldebuginfo_end:
+	.section	.debug_abbrev,"",@progbits
+.Ldebug_abbrev0:
+	.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 0x42	# (DW_AT_identifier_case)
+	.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 0x17	# (DW_FORM_sec_offset)
+	.byte	0
+	.byte	0
+	.uleb128 0x2	# (abbrev code)
+	.uleb128 0x2e	# (TAG: DW_TAG_subprogram)
+	.byte	0x1	# DW_children_yes
+	.uleb128 0x3f	# (DW_AT_external)
+	.uleb128 0x19	# (DW_FORM_flag_present)
+	.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 0x6e	# (DW_AT_linkage_name)
+	.uleb128 0x8	# (DW_FORM_string)
+	.uleb128 0x11	# (DW_AT_low_pc)
+	.uleb128 0x1	# (DW_FORM_addr)
+	.uleb128 0x12	# (DW_AT_high_pc)
+	.uleb128 0x1	# (DW_FORM_addr)
+	.uleb128 0x40	# (DW_AT_frame_base)
+	.uleb128 0x18	# (DW_FORM_exprloc)
+	.uleb128 0x2116	# (DW_AT_GNU_all_tail_call_sites)
+	.uleb128 0x19	# (DW_FORM_flag_present)
+	.uleb128 0x1	# (DW_AT_sibling)
+	.uleb128 0x13	# (DW_FORM_ref4)
+	.byte	0
+	.byte	0
+	.uleb128 0x3	# (abbrev code)
+	.uleb128 0x1a	# (TAG: DW_TAG_common_block)
+	.byte	0x1	# DW_children_yes
+	.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 0x6e	# (DW_AT_linkage_name)
+	.uleb128 0xe	# (DW_FORM_strp)
+	.uleb128 0x2	# (DW_AT_location)
+	.uleb128 0x18	# (DW_FORM_exprloc)
+	.uleb128 0x1	# (DW_AT_sibling)
+	.uleb128 0x13	# (DW_FORM_ref4)
+	.byte	0
+	.byte	0
+	.uleb128 0x4	# (abbrev code)
+	.uleb128 0x34	# (TAG: DW_TAG_variable)
+	.byte	0	# 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 0x19	# (DW_FORM_flag_present)
+	.uleb128 0x2	# (DW_AT_location)
+	.uleb128 0x18	# (DW_FORM_exprloc)
+	.byte	0
+	.byte	0
+	.uleb128 0x5	# (abbrev code)
+	.uleb128 0x1a	# (TAG: DW_TAG_common_block)
+	.byte	0x1	# DW_children_yes
+	.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 0x6e	# (DW_AT_linkage_name)
+	.uleb128 0xe	# (DW_FORM_strp)
+	.uleb128 0x2	# (DW_AT_location)
+	.uleb128 0x18	# (DW_FORM_exprloc)
+	.uleb128 0x1	# (DW_AT_sibling)
+	.uleb128 0x13	# (DW_FORM_ref4)
+	.byte	0
+	.byte	0
+	.uleb128 0x6	# (abbrev code)
+	.uleb128 0x34	# (TAG: DW_TAG_variable)
+	.byte	0	# 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 0x3f	# (DW_AT_external)
+	.uleb128 0x19	# (DW_FORM_flag_present)
+	.uleb128 0x2	# (DW_AT_location)
+	.uleb128 0x18	# (DW_FORM_exprloc)
+	.byte	0
+	.byte	0
+	.uleb128 0x7	# (abbrev code)
+	.uleb128 0x34	# (TAG: DW_TAG_variable)
+	.byte	0	# 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 0x2	# (DW_AT_location)
+	.uleb128 0x18	# (DW_FORM_exprloc)
+	.byte	0
+	.byte	0
+	.uleb128 0x8	# (abbrev code)
+	.uleb128 0x34	# (TAG: DW_TAG_variable)
+	.byte	0	# 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 0x2	# (DW_AT_location)
+	.uleb128 0x18	# (DW_FORM_exprloc)
+	.byte	0
+	.byte	0
+	.uleb128 0x9	# (abbrev code)
+	.uleb128 0x24	# (TAG: DW_TAG_base_type)
+	.byte	0	# 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 0xe	# (DW_FORM_strp)
+	.byte	0
+	.byte	0
+	.uleb128 0xa	# (abbrev code)
+	.uleb128 0x2e	# (TAG: DW_TAG_subprogram)
+	.byte	0x1	# DW_children_yes
+	.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 0x11	# (DW_AT_low_pc)
+	.uleb128 0x1	# (DW_FORM_addr)
+	.uleb128 0x12	# (DW_AT_high_pc)
+	.uleb128 0x1	# (DW_FORM_addr)
+	.uleb128 0x40	# (DW_AT_frame_base)
+	.uleb128 0x18	# (DW_FORM_exprloc)
+	.uleb128 0x2116	# (DW_AT_GNU_all_tail_call_sites)
+	.uleb128 0x19	# (DW_FORM_flag_present)
+	.uleb128 0x6a	# (DW_AT_main_subprogram)
+	.uleb128 0x19	# (DW_FORM_flag_present)
+	.uleb128 0x36	# (DW_AT_calling_convention)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x1	# (DW_AT_sibling)
+	.uleb128 0x13	# (DW_FORM_ref4)
+	.byte	0
+	.byte	0
+	.uleb128 0xb	# (abbrev code)
+	.uleb128 0x1a	# (TAG: DW_TAG_common_block)
+	.byte	0x1	# DW_children_yes
+	.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 0x6e	# (DW_AT_linkage_name)
+	.uleb128 0xe	# (DW_FORM_strp)
+	.uleb128 0x2	# (DW_AT_location)
+	.uleb128 0x18	# (DW_FORM_exprloc)
+	.byte	0
+	.byte	0
+	.uleb128 0xc	# (abbrev code)
+	.uleb128 0x2e	# (TAG: DW_TAG_subprogram)
+	.byte	0x1	# DW_children_yes
+	.uleb128 0x3f	# (DW_AT_external)
+	.uleb128 0x19	# (DW_FORM_flag_present)
+	.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 0x11	# (DW_AT_low_pc)
+	.uleb128 0x1	# (DW_FORM_addr)
+	.uleb128 0x12	# (DW_AT_high_pc)
+	.uleb128 0x1	# (DW_FORM_addr)
+	.uleb128 0x40	# (DW_AT_frame_base)
+	.uleb128 0x18	# (DW_FORM_exprloc)
+	.uleb128 0x2116	# (DW_AT_GNU_all_tail_call_sites)
+	.uleb128 0x19	# (DW_FORM_flag_present)
+	.uleb128 0x1	# (DW_AT_sibling)
+	.uleb128 0x13	# (DW_FORM_ref4)
+	.byte	0
+	.byte	0
+	.uleb128 0xd	# (abbrev code)
+	.uleb128 0x5	# (TAG: DW_TAG_formal_parameter)
+	.byte	0	# 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 0x2	# (DW_AT_location)
+	.uleb128 0x18	# (DW_FORM_exprloc)
+	.byte	0
+	.byte	0
+	.uleb128 0xe	# (abbrev code)
+	.uleb128 0x26	# (TAG: DW_TAG_const_type)
+	.byte	0	# DW_children_no
+	.uleb128 0x49	# (DW_AT_type)
+	.uleb128 0x13	# (DW_FORM_ref4)
+	.byte	0
+	.byte	0
+	.uleb128 0xf	# (abbrev code)
+	.uleb128 0xf	# (TAG: DW_TAG_pointer_type)
+	.byte	0	# 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	0
+	.byte	0
+	.uleb128 0x10	# (abbrev code)
+	.uleb128 0x34	# (TAG: DW_TAG_variable)
+	.byte	0	# 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 0x19	# (DW_FORM_flag_present)
+	.uleb128 0x38	# (DW_AT_data_member_location)
+	.uleb128 0x18	# (DW_FORM_exprloc)
+	.byte	0
+	.byte	0
+	.byte	0
+	.section	.debug_aranges,"",@progbits
+	.long	0x2c	# Length of Address Ranges Info
+	.value	0x2	# DWARF Version
+	.long	.Ldebug_info0	# Offset of Compilation Unit Info
+	.byte	0x8	# Size of Address
+	.byte	0	# Size of Segment Descriptor
+	.value	0	# Pad to 16 byte boundary
+	.value	0
+	.quad	.Ltext0	# Address
+	.quad	.Letext0-.Ltext0	# Length
+	.quad	0
+	.quad	0
+	.section	.debug_line,"",@progbits
+.Ldebug_line0:
+	.section	.debug_str,"MS",@progbits,1
+.LASF0:
+	.string	"fo_o"
+.LASF8:
+	.string	"fo_o_"
+.LASF3:
+	.string	"iz_z2"
+.LASF1:
+	.string	"ix_x"
+.LASF9:
+	.string	"main"
+.LASF4:
+	.string	"iz_z"
+.LASF13:
+	.string	"GNU Fortran 4.6.3 20120306 (Red Hat 4.6.3-2) -mtune=generic -march=x86-64 -g -fintrinsic-modules-path /usr/lib/gcc/x86_64-redhat-linux/4.6.3/finclude"
+.LASF16:
+	.string	"foo_"
+.LASF7:
+	.string	"real(kind=8)"
+.LASF5:
+	.string	"integer(kind=4)"
+.LASF17:
+	.string	"common_test"
+.LASF12:
+	.string	"character(kind=1)"
+.LASF14:
+	.string	"../gdb.fortran/common-block.f90"
+.LASF10:
+	.string	"argc"
+.LASF2:
+	.string	"iy_y"
+.LASF11:
+	.string	"argv"
+.LASF15:
+	.string	"/home/tromey/gnu/archer/archer/gdb/testsuite/gdb.dwarf2"
+.LASF6:
+	.string	"real(kind=4)"
+	.ident	"GCC: (GNU) 4.6.3 20120306 (Red Hat 4.6.3-2)"
+	.section	.note.GNU-stack,"",@progbits
diff --git a/gdb/testsuite/gdb.dwarf2/dw2-common-block.exp b/gdb/testsuite/gdb.dwarf2/dw2-common-block.exp
new file mode 100644
index 0000000..a1914ee
--- /dev/null
+++ b/gdb/testsuite/gdb.dwarf2/dw2-common-block.exp
@@ -0,0 +1,50 @@
+# Copyright 2012 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/>.
+
+load_lib dwarf.exp
+
+# This test can only be run on targets which support DWARF-2 and use gas.
+if ![dwarf2_support] {
+    return 0  
+}
+
+# This test can only be run on x86-64 targets.
+if {![istarget x86_64-*] || ![is_lp64_target]} {
+    return 0
+}
+
+# It requires fortran.
+if {[skip_fortran_tests]} {
+    return 0
+}
+
+standard_testfile .S
+
+if { [prepare_for_testing "${testfile}.exp" "${testfile}" $srcfile \
+	  {nodebug f90}] } {
+    return -1
+}
+
+if ![runto MAIN__] then {
+    perror "couldn't run to breakpoint MAIN__"
+    continue
+}
+
+gdb_breakpoint [gdb_get_line_number "stop-here-out" \
+		    ../gdb.fortran/common-block.f90]
+gdb_continue_to_breakpoint "stop-here-out"
+
+gdb_test "p ix" " = 1" "p ix out"
+gdb_test "p iy" " = 2" "p iy out"
-- 
1.7.7.6

Re: [3/3] RFC - optional patch to restore DW_AT_data_member_location

[Doug Evans]

On Tue, Aug 21, 2012 at 9:37 AM, Tom Tromey <tromey@redhat.com> wrote:
> This patch reimplements DW_AT_data_member_location for variables
> appearing in a Fortran common block.
>
> This attribute is not specified by DWARF.  It is apparently an old
> approach used by gfortran prior to 2008; at least it appeared in
>
>     http://gcc.gnu.org/bugzilla/show_bug.cgi?id=23057
>
> This patch is based on the idea that such attributes are relatively
> rare.  So, rather than implement complicated support for them, gdb just
> rewrites them into an ordinary location expression that uses the common
> block's location as a subroutine.
>
> I've included a new test case, which I made by editing the assembly
> output of gfortran by hand.
>
> Built and regtested on x86-64 Fedora 16.
>
> I consider this patch optional, because I think it is too much
> complicated code in support of a marginal and obsolete feature.
> However, I wrote it in case someone thinks that supporting 4 year old
> versions of gfortran is important.
>
> Tom
>
>         * dwarf2read.c (mark_common_block_symbol_computed): New function.
>         (read_common_block): Handle child DIEs with
>         DW_AT_data_member_location.
>         (new_symbol_full): Add special case for common blocks.
>
>         * gdb.dwarf2/dw2-common-block.S: New file.
>         * gdb.dwarf2/dw2-common-block.exp: New file.

I'm all for holding off until someone presents a *compelling* use case.

Re: [3/3] RFC - optional patch to restore DW_AT_data_member_location

[Jan Kratochvil]

On Wed, 22 Aug 2012 00:12:08 +0200, Doug Evans wrote:
> On Tue, Aug 21, 2012 at 9:37 AM, Tom Tromey <tromey@redhat.com> wrote:
> > I consider this patch optional, because I think it is too much
> > complicated code in support of a marginal and obsolete feature.
> > However, I wrote it in case someone thinks that supporting 4 year old
> > versions of gfortran is important.
> 
> I'm all for holding off until someone presents a *compelling* use case.

The use case is that if not upstreamed I will have to continue carrying on the
patch up to date with HEAD for many further years for compatibility with
gfortran-4.1 in RHEL-5.y.

Sure it may not be compelling for FSF GDB, I am fine with that.
FYI older GCCs are still actively in use, even if not actively then just due
to existing built binaries/libraries.


Thanks,
Jan

Re: [3/3] RFC - optional patch to restore DW_AT_data_member_location

[Joel Brobecker]

> The use case is that if not upstreamed I will have to continue carrying on the
> patch up to date with HEAD for many further years for compatibility with
> gfortran-4.1 in RHEL-5.y.
> 
> Sure it may not be compelling for FSF GDB, I am fine with that.

Personally, I think it is potentially helpful to have it in the FSF
tree unless it causes problems. I can certainly see someone upgrading
their GDB from source, while still using the compiler provided by the
system.

-- 
Joel

Re: [3/3] RFC - optional patch to restore DW_AT_data_member_location

[Tom Tromey]

Jan> The use case is that if not upstreamed I will have to continue
Jan> carrying on the patch up to date with HEAD for many further years
Jan> for compatibility with gfortran-4.1 in RHEL-5.y.

Joel> Personally, I think it is potentially helpful to have it in the FSF
Joel> tree unless it causes problems. I can certainly see someone upgrading
Joel> their GDB from source, while still using the compiler provided by the
Joel> system.

I'll include the patch when I commit this series.

Tom

Re: [3/3] RFC - optional patch to restore DW_AT_data_member_location

[Jan Kratochvil]

On Tue, 21 Aug 2012 18:37:33 +0200, Tom Tromey wrote:
> --- a/gdb/dwarf2read.c
> +++ b/gdb/dwarf2read.c
> @@ -11060,6 +11060,71 @@ read_set_type (struct die_info *die, struct dwarf2_cu *cu)
>    return set_die_type (die, set_type, cu);
>  }
>  
> +/* A helper for read_common_block that creates a locexpr baton.  */

I believe still the parameters should be documented in this case.

> +
> +static void
> +mark_common_block_symbol_computed (struct symbol *sym,
> +				   struct die_info *common_die,
> +				   struct attribute *common_loc,
> +				   struct attribute *member_loc,
> +				   struct dwarf2_cu *cu)
> +{
> +  struct objfile *objfile = dwarf2_per_objfile->objfile;
> +  struct dwarf2_locexpr_baton *baton;
> +  gdb_byte *ptr;
> +  unsigned int cu_off;
> +  enum bfd_endian byte_order = gdbarch_byte_order (get_objfile_arch (objfile));
> +  LONGEST offset;
> +
> +  gdb_assert (common_loc && member_loc);
> +  gdb_assert (attr_form_is_block (common_loc));
> +  gdb_assert (attr_form_is_block (member_loc)
> +	      || attr_form_is_constant (member_loc));
> +
> +  baton = obstack_alloc (&objfile->objfile_obstack,
> +			 sizeof (struct dwarf2_locexpr_baton));
> +  baton->per_cu = cu->per_cu;
> +  gdb_assert (baton->per_cu);
> +
> +  baton->size = 5 /* DW_OP_call4 */ + 1 /* DW_OP_plus */;
> +
> +  if (attr_form_is_constant (member_loc))
> +    {
> +      offset = dwarf2_get_attr_constant_value (member_loc, 0);
> +      baton->size += 1 /* DW_OP_addr */ + cu->header.addr_size;
> +    }
> +  else
> +    baton->size += DW_BLOCK (member_loc)->size;
> +
> +  ptr = obstack_alloc (&objfile->objfile_obstack, baton->size);
> +  baton->data = ptr;
> +
> +  *ptr++ = DW_OP_call4;
> +  cu_off = common_die->offset.sect_off - cu->per_cu->offset.sect_off;
> +  store_unsigned_integer (ptr, 4, byte_order, cu_off);
> +  ptr += 4;
> +
> +  if (attr_form_is_constant (member_loc))
> +    {
> +      *ptr++ = DW_OP_addr;
> +      store_unsigned_integer (ptr, cu->header.addr_size, byte_order, offset);
> +      ptr += cu->header.addr_size;
> +    }
> +  else
> +    {
> +      /* We have to copy the data here, because DW_OP_call4 will only
> +	 use a DW_AT_location attribute.  */
> +      memcpy (ptr, DW_BLOCK (member_loc)->data, DW_BLOCK (member_loc)->size);
> +      ptr += DW_BLOCK (member_loc)->size;
> +    }
> +
> +  *ptr = DW_OP_plus;

I think this code is complicted enough to be worth an assertion:
     *ptr++ = DW_OP_plus;
     gdb_assert (ptr - baton->data == baton->size);


> +
> +  SYMBOL_COMPUTED_OPS (sym) = &dwarf2_locexpr_funcs;
> +  SYMBOL_LOCATION_BATON (sym) = baton;
> +  SYMBOL_CLASS (sym) = LOC_COMPUTED;
> +}
> +
>  /* Create appropriate locally-scoped variables for all the
>     DW_TAG_common_block entries.  Also create a struct
>     fortran_common_block listing all such variables for `info common'.
[...]
> --- /dev/null
> +++ b/gdb/testsuite/gdb.dwarf2/dw2-common-block.S
[...]
> +.LASF13:
> +	.string	"GNU Fortran 4.6.3 20120306 (Red Hat 4.6.3-2) -mtune=generic -march=x86-64 -g -fintrinsic-modules-path /usr/lib/gcc/x86_64-redhat-linux/4.6.3/finclude"

Probably not needing to be rebuilt but I think for FSF GDB it would be better
to precompile such .S files using FSF GCC, which could be possibly (more
easily) reproduced in the future.


[...]
> +.LASF14:
> +	.string	"../gdb.fortran/common-block.f90"
[...]
> +.LASF15:
> +	.string	"/home/tromey/gnu/archer/archer/gdb/testsuite/gdb.dwarf2"

(gdb) l
48  ../gdb.fortran/common-block.f90: No such file or directory.

While with:
-       .string "/home/tromey/gnu/archer/archer/gdb/testsuite/gdb.dwarf2"
+       .string "gdb.dwarf2"

it would work:
(gdb) l
48     REAL*8               iz
[...]


> +.LASF6:
> +	.string	"real(kind=4)"
> +	.ident	"GCC: (GNU) 4.6.3 20120306 (Red Hat 4.6.3-2)"
> +	.section	.note.GNU-stack,"",@progbits


Thanks,
Jan

Re: [3/3] RFC - optional patch to restore DW_AT_data_member_location

[Tom Tromey]

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

>> +/* A helper for read_common_block that creates a locexpr baton.  */

Jan> I believe still the parameters should be documented in this case.

I did this.

Jan> I think this code is complicted enough to be worth an assertion:
Jan>      *ptr++ = DW_OP_plus;
Jan>      gdb_assert (ptr - baton->data == baton->size);

This too.

>> +	.string	"GNU Fortran 4.6.3 20120306 (Red Hat 4.6.3-2) -mtune=generic -march=x86-64 -g -fintrinsic-modules-path /usr/lib/gcc/x86_64-redhat-linux/4.6.3/finclude"

Jan> Probably not needing to be rebuilt but I think for FSF GDB it would
Jan> be better to precompile such .S files using FSF GCC, which could be
Jan> possibly (more easily) reproduced in the future.

I had to edit the .S file.  I would not want to try to reproduce this.
I guess if I was going to do it again I would try to use my DWARF
assembler instead.

I changed the string to

"GNU Fortran 4.6.3 plus hand hackery"

... which is reasonably true.

>> +.LASF15:
>> +	.string	"/home/tromey/gnu/archer/archer/gdb/testsuite/gdb.dwarf2"

Jan> While with:
Jan> -       .string "/home/tromey/gnu/archer/archer/gdb/testsuite/gdb.dwarf2"
Jan> +       .string "gdb.dwarf2"

Jan> it would work:
Jan> (gdb) l
Jan> 48     REAL*8               iz
Jan> [...]

This didn't work for me, I guess since I build out-of-tree.  I guess it
would work with a "dir" command.  I made the change anyhow.

Tom

Re: [3/3] RFC - optional patch to restore DW_AT_data_member_location

[Jan Kratochvil]

On Tue, 11 Sep 2012 22:56:11 +0200, Tom Tromey wrote:
> >> +	.string	"GNU Fortran 4.6.3 20120306 (Red Hat 4.6.3-2) -mtune=generic -march=x86-64 -g -fintrinsic-modules-path /usr/lib/gcc/x86_64-redhat-linux/4.6.3/finclude"
> 
> Jan> Probably not needing to be rebuilt but I think for FSF GDB it would
> Jan> be better to precompile such .S files using FSF GCC, which could be
> Jan> possibly (more easily) reproduced in the future.
> 
> I had to edit the .S file.  I would not want to try to reproduce this.
> I guess if I was going to do it again I would try to use my DWARF
> assembler instead.
> 
> I changed the string to
> 
> "GNU Fortran 4.6.3 plus hand hackery"
> 
> ... which is reasonably true.

I see I did not make clear why I like the reproducibility of the compilation.
This is because sometimes it is good to know what was hand-edited in the file
and I find a bit excessive to keep both the original and the hand-edited .S
files in the repository due to it.  This is why I sometimes
did #if 0-#else-#endif or #if 0-#endif-#if 1-#endif constructs in the .S
files (I see it now only in gdb.dwarf2/dw2-const.S).

I sure do not insist on anything like that, just FYI.


Thanks,
Jan

Re: [3/3] RFC - optional patch to restore DW_AT_data_member_location

[Tom Tromey]

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

Jan> I see I did not make clear why I like the reproducibility of the
Jan> compilation.  This is because sometimes it is good to know what was
Jan> hand-edited in the file and I find a bit excessive to keep both the
Jan> original and the hand-edited .S files in the repository due to it.
Jan> This is why I sometimes did #if 0-#else-#endif or #if 0-#endif-#if
Jan> 1-#endif constructs in the .S files (I see it now only in
Jan> gdb.dwarf2/dw2-const.S).

Ok.

Jan> I sure do not insist on anything like that, just FYI.

I'll at least add some comments to the .S.
I suppose this is another way that having a DWARF assembler would be
preferable.

Tom

Re: [3/3] RFC - optional patch to restore DW_AT_data_member_location

[Tom Tromey]

>>>>> "Tom" == Tom Tromey <tromey@redhat.com> writes:

Tom> I'll at least add some comments to the .S.
Tom> I suppose this is another way that having a DWARF assembler would be
Tom> preferable.

I recreated the .S and edited in some #ifs so you can see what the
changes are.

Tom

Re: [3/3] RFC - optional patch to restore DW_AT_data_member_location

[Tom Tromey]

>>>>> "Tom" == Tom Tromey <tromey@redhat.com> writes:

Tom> This patch reimplements DW_AT_data_member_location for variables
Tom> appearing in a Fortran common block.

Here's the refreshed patch.
I believe I've addressed all the comments.
Regtested on x86-64 F16.

Tom

	* dwarf2read.c (mark_common_block_symbol_computed): New function.
	(read_common_block): Handle child DIEs with
	DW_AT_data_member_location.
	(new_symbol_full): Add special case for common blocks.

	* gdb.dwarf2/dw2-common-block.S: New file.
	* gdb.dwarf2/dw2-common-block.exp: New file.
---
 gdb/dwarf2read.c                              |  146 ++++-
 gdb/testsuite/gdb.dwarf2/dw2-common-block.S   |  872 +++++++++++++++++++++++++
 gdb/testsuite/gdb.dwarf2/dw2-common-block.exp |   50 ++
 3 files changed, 1064 insertions(+), 4 deletions(-)
 create mode 100644 gdb/testsuite/gdb.dwarf2/dw2-common-block.S
 create mode 100644 gdb/testsuite/gdb.dwarf2/dw2-common-block.exp

diff --git a/gdb/dwarf2read.c b/gdb/dwarf2read.c
index 9e0e0af..9b758dc 100644
--- a/gdb/dwarf2read.c
+++ b/gdb/dwarf2read.c
@@ -11059,6 +11059,79 @@ read_set_type (struct die_info *die, struct dwarf2_cu *cu)
   return set_die_type (die, set_type, cu);
 }
 
+/* A helper for read_common_block that creates a locexpr baton.
+   SYM is the symbol which we are marking as computed.
+   COMMON_DIE is the DIE for the common block.
+   COMMON_LOC is the location expression attribute for the common
+   block itself.
+   MEMBER_LOC is the location expression attribute for the particular
+   member of the common block that we are processing.
+   CU is the CU from which the above come.  */
+
+static void
+mark_common_block_symbol_computed (struct symbol *sym,
+				   struct die_info *common_die,
+				   struct attribute *common_loc,
+				   struct attribute *member_loc,
+				   struct dwarf2_cu *cu)
+{
+  struct objfile *objfile = dwarf2_per_objfile->objfile;
+  struct dwarf2_locexpr_baton *baton;
+  gdb_byte *ptr;
+  unsigned int cu_off;
+  enum bfd_endian byte_order = gdbarch_byte_order (get_objfile_arch (objfile));
+  LONGEST offset;
+
+  gdb_assert (common_loc && member_loc);
+  gdb_assert (attr_form_is_block (common_loc));
+  gdb_assert (attr_form_is_block (member_loc)
+	      || attr_form_is_constant (member_loc));
+
+  baton = obstack_alloc (&objfile->objfile_obstack,
+			 sizeof (struct dwarf2_locexpr_baton));
+  baton->per_cu = cu->per_cu;
+  gdb_assert (baton->per_cu);
+
+  baton->size = 5 /* DW_OP_call4 */ + 1 /* DW_OP_plus */;
+
+  if (attr_form_is_constant (member_loc))
+    {
+      offset = dwarf2_get_attr_constant_value (member_loc, 0);
+      baton->size += 1 /* DW_OP_addr */ + cu->header.addr_size;
+    }
+  else
+    baton->size += DW_BLOCK (member_loc)->size;
+
+  ptr = obstack_alloc (&objfile->objfile_obstack, baton->size);
+  baton->data = ptr;
+
+  *ptr++ = DW_OP_call4;
+  cu_off = common_die->offset.sect_off - cu->per_cu->offset.sect_off;
+  store_unsigned_integer (ptr, 4, byte_order, cu_off);
+  ptr += 4;
+
+  if (attr_form_is_constant (member_loc))
+    {
+      *ptr++ = DW_OP_addr;
+      store_unsigned_integer (ptr, cu->header.addr_size, byte_order, offset);
+      ptr += cu->header.addr_size;
+    }
+  else
+    {
+      /* We have to copy the data here, because DW_OP_call4 will only
+	 use a DW_AT_location attribute.  */
+      memcpy (ptr, DW_BLOCK (member_loc)->data, DW_BLOCK (member_loc)->size);
+      ptr += DW_BLOCK (member_loc)->size;
+    }
+
+  *ptr++ = DW_OP_plus;
+  gdb_assert (ptr - baton->data == baton->size);
+
+  SYMBOL_COMPUTED_OPS (sym) = &dwarf2_locexpr_funcs;
+  SYMBOL_LOCATION_BATON (sym) = baton;
+  SYMBOL_CLASS (sym) = LOC_COMPUTED;
+}
+
 /* Create appropriate locally-scoped variables for all the
    DW_TAG_common_block entries.  Also create a struct common_block
    listing all such variables for `info common'.  COMMON_BLOCK_DOMAIN
@@ -11068,6 +11141,29 @@ read_set_type (struct die_info *die, struct dwarf2_cu *cu)
 static void
 read_common_block (struct die_info *die, struct dwarf2_cu *cu)
 {
+  struct attribute *attr;
+
+  attr = dwarf2_attr (die, DW_AT_location, cu);
+  if (attr)
+    {
+      /* Support the .debug_loc offsets.  */
+      if (attr_form_is_block (attr))
+        {
+	  /* Ok.  */
+        }
+      else if (attr_form_is_section_offset (attr))
+        {
+	  dwarf2_complex_location_expr_complaint ();
+	  attr = NULL;
+        }
+      else
+        {
+	  dwarf2_invalid_attrib_class_complaint ("DW_AT_location",
+						 "common block member");
+	  attr = NULL;
+        }
+    }
+
   if (die->child != NULL)
     {
       struct objfile *objfile = cu->objfile;
@@ -11094,8 +11190,39 @@ read_common_block (struct die_info *die, struct dwarf2_cu *cu)
 	  /* Create the symbol in the DW_TAG_common_block block in the current
 	     symbol scope.  */
 	  sym = new_symbol (child_die, NULL, cu);
-	  if (sym)
-	    common_block->contents[common_block->n_entries++] = sym;
+	  if (sym != NULL)
+	    {
+	      struct attribute *member_loc;
+
+	      common_block->contents[common_block->n_entries++] = sym;
+
+	      member_loc = dwarf2_attr (child_die, DW_AT_data_member_location,
+					cu);
+	      if (member_loc)
+		{
+		  /* GDB has handled this for a long time, but it is
+		     not specified by DWARF.  It seems to have been
+		     emitted by gfortran at least as recently as:
+		     http://gcc.gnu.org/bugzilla/show_bug.cgi?id=23057.  */
+		  complaint (&symfile_complaints,
+			     _("Variable in common block has "
+			       "DW_AT_data_member_location "
+			       "- DIE at 0x%x [in module %s]"),
+			     child_die->offset.sect_off, cu->objfile->name);
+
+		  if (attr_form_is_section_offset (member_loc))
+		    dwarf2_complex_location_expr_complaint ();
+		  else if (attr_form_is_constant (member_loc)
+			   || attr_form_is_block (member_loc))
+		    {
+		      if (attr)
+			mark_common_block_symbol_computed (sym, die, attr,
+							   member_loc, cu);
+		    }
+		  else
+		    dwarf2_complex_location_expr_complaint ();
+		}
+	    }
 	}
 
       sym = new_symbol (die, objfile_type (objfile)->builtin_void, cu);
@@ -14995,8 +15122,19 @@ new_symbol_full (struct die_info *die, struct type *type, struct dwarf2_cu *cu,
 	         the minimal symbol table whenever the variable is
 	         referenced.  */
 	      attr2 = dwarf2_attr (die, DW_AT_external, cu);
-	      if (attr2 && (DW_UNSND (attr2) != 0)
-		  && dwarf2_attr (die, DW_AT_type, cu) != NULL)
+
+	      /* Fortran explicitly imports any global symbols to the local
+		 scope by DW_TAG_common_block.  */
+	      if (cu->language == language_fortran && die->parent
+		  && die->parent->tag == DW_TAG_common_block)
+		{
+		  /* SYMBOL_CLASS doesn't matter here because
+		     read_common_block is going to reset it.  */
+		  if (!suppress_add)
+		    list_to_add = cu->list_in_scope;
+		}
+	      else if (attr2 && (DW_UNSND (attr2) != 0)
+		       && dwarf2_attr (die, DW_AT_type, cu) != NULL)
 		{
 		  /* A variable with DW_AT_external is never static, but it
 		     may be block-scoped.  */
diff --git a/gdb/testsuite/gdb.dwarf2/dw2-common-block.S b/gdb/testsuite/gdb.dwarf2/dw2-common-block.S
new file mode 100644
index 0000000..ec6c6ae
--- /dev/null
+++ b/gdb/testsuite/gdb.dwarf2/dw2-common-block.S
@@ -0,0 +1,872 @@
+/* This testcase is part of GDB, the GNU debugger.
+
+   Copyright 2012 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 was made from ../gdb.fortran/common-block.f90 using
+	gfortran -dA -S -g
+   and then hand-editing the assembly a bit to introduce
+   DW_AT_data_member_location.
+
+   Search for "#if 0" in this file to see the important edits.  */
+
+	.file	"common-block.f90"
+	.text
+.Ltext0:
+	.globl	in_
+	.type	in_, @function
+in_:
+.LFB0:
+	.file 1 "../gdb.fortran/common-block.f90"
+	# ../gdb.fortran/common-block.f90:21
+	.loc 1 21 0
+	.cfi_startproc
+	# basic block 2
+	pushq	%rbp
+	.cfi_def_cfa_offset 16
+	.cfi_offset 6, -16
+	movq	%rsp, %rbp
+	.cfi_def_cfa_register 6
+	subq	$16, %rsp
+	# ../gdb.fortran/common-block.f90:34
+	.loc 1 34 0
+	movl	$5, -4(%rbp)
+	# ../gdb.fortran/common-block.f90:35
+	.loc 1 35 0
+	movl	$55, -8(%rbp)
+	# ../gdb.fortran/common-block.f90:21
+	.loc 1 21 0
+	movl	fo_o_(%rip), %eax
+	# ../gdb.fortran/common-block.f90:37
+	.loc 1 37 0
+	cmpl	$11, %eax
+	jne	.L2
+	# basic block 3
+	# ../gdb.fortran/common-block.f90:21
+	.loc 1 21 0 discriminator 2
+	movss	fo_o_+4(%rip), %xmm0
+	# ../gdb.fortran/common-block.f90:37
+	.loc 1 37 0 discriminator 2
+	ucomiss	.LC0(%rip), %xmm0
+	jp	.L2
+	# basic block 4
+	ucomiss	.LC0(%rip), %xmm0
+	jne	.L2
+	# basic block 5
+	# ../gdb.fortran/common-block.f90:21
+	.loc 1 21 0 discriminator 3
+	movsd	fo_o_+8(%rip), %xmm0
+	# ../gdb.fortran/common-block.f90:37
+	.loc 1 37 0 discriminator 3
+	ucomisd	.LC1(%rip), %xmm0
+	jp	.L2
+	# basic block 6
+	ucomisd	.LC1(%rip), %xmm0
+	je	.L8
+.L2:
+	# basic block 7
+	# ../gdb.fortran/common-block.f90:37
+	.loc 1 37 0 is_stmt 0 discriminator 1
+	movl	$0, %eax
+	call	_gfortran_abort
+.L8:
+	# basic block 8
+	# ../gdb.fortran/common-block.f90:21
+	.loc 1 21 0 is_stmt 1
+	movl	foo_(%rip), %eax
+	# ../gdb.fortran/common-block.f90:38
+	.loc 1 38 0
+	cmpl	$1, %eax
+	jne	.L5
+	# basic block 9
+	# ../gdb.fortran/common-block.f90:21
+	.loc 1 21 0 discriminator 2
+	movss	foo_+4(%rip), %xmm0
+	# ../gdb.fortran/common-block.f90:38
+	.loc 1 38 0 discriminator 2
+	ucomiss	.LC2(%rip), %xmm0
+	jp	.L5
+	# basic block 10
+	ucomiss	.LC2(%rip), %xmm0
+	jne	.L5
+	# basic block 11
+	# ../gdb.fortran/common-block.f90:21
+	.loc 1 21 0 discriminator 3
+	movsd	foo_+8(%rip), %xmm0
+	# ../gdb.fortran/common-block.f90:38
+	.loc 1 38 0 discriminator 3
+	ucomisd	.LC3(%rip), %xmm0
+	jp	.L5
+	# basic block 12
+	ucomisd	.LC3(%rip), %xmm0
+	je	.L9
+.L5:
+	# basic block 13
+	# ../gdb.fortran/common-block.f90:38
+	.loc 1 38 0 is_stmt 0 discriminator 1
+	movl	$0, %eax
+	call	_gfortran_abort
+.L9:
+	# basic block 14
+	# ../gdb.fortran/common-block.f90:40
+	.loc 1 40 0 is_stmt 1
+	movl	$0, fo_o_(%rip)
+	# ../gdb.fortran/common-block.f90:42
+	.loc 1 42 0
+	leave
+	.cfi_def_cfa 7, 8
+	ret
+	.cfi_endproc
+.LFE0:
+	.size	in_, .-in_
+	.type	MAIN__, @function
+MAIN__:
+.LFB1:
+	# ../gdb.fortran/common-block.f90:44
+	.loc 1 44 0
+	.cfi_startproc
+	# basic block 2
+	pushq	%rbp
+	.cfi_def_cfa_offset 16
+	.cfi_offset 6, -16
+	movq	%rsp, %rbp
+	.cfi_def_cfa_register 6
+	# ../gdb.fortran/common-block.f90:57
+	.loc 1 57 0
+	movl	$1, foo_(%rip)
+	# ../gdb.fortran/common-block.f90:58
+	.loc 1 58 0
+	movl	$0x40000000, %eax
+	movl	%eax, foo_+4(%rip)
+	# ../gdb.fortran/common-block.f90:59
+	.loc 1 59 0
+	movabsq	$4613937818241073152, %rax
+	movq	%rax, foo_+8(%rip)
+	# ../gdb.fortran/common-block.f90:61
+	.loc 1 61 0
+	movl	$11, fo_o_(%rip)
+	# ../gdb.fortran/common-block.f90:62
+	.loc 1 62 0
+	movl	$0x41b00000, %eax
+	movl	%eax, fo_o_+4(%rip)
+	# ../gdb.fortran/common-block.f90:63
+	.loc 1 63 0
+	movabsq	$4629841154425225216, %rax
+	movq	%rax, fo_o_+8(%rip)
+	# ../gdb.fortran/common-block.f90:65
+	.loc 1 65 0
+	movl	$0, %eax
+	call	in_
+	# ../gdb.fortran/common-block.f90:67
+	.loc 1 67 0
+	popq	%rbp
+	.cfi_def_cfa 7, 8
+	ret
+	.cfi_endproc
+.LFE1:
+	.size	MAIN__, .-MAIN__
+	.globl	main
+	.type	main, @function
+main:
+.LFB2:
+	# ../gdb.fortran/common-block.f90:67
+	.loc 1 67 0
+	.cfi_startproc
+	# basic block 2
+	pushq	%rbp
+	.cfi_def_cfa_offset 16
+	.cfi_offset 6, -16
+	movq	%rsp, %rbp
+	.cfi_def_cfa_register 6
+	subq	$16, %rsp
+	movl	%edi, -4(%rbp)
+	movq	%rsi, -16(%rbp)
+	# ../gdb.fortran/common-block.f90:67
+	.loc 1 67 0
+	movq	-16(%rbp), %rdx
+	movl	-4(%rbp), %eax
+	movq	%rdx, %rsi
+	movl	%eax, %edi
+	call	_gfortran_set_args
+	movl	$options.0.1570, %esi
+	movl	$8, %edi
+	call	_gfortran_set_options
+	call	MAIN__
+	movl	$0, %eax
+	leave
+	.cfi_def_cfa 7, 8
+	ret
+	.cfi_endproc
+.LFE2:
+	.size	main, .-main
+	.comm	foo_,16,16
+	.comm	fo_o_,16,16
+	.section	.rodata
+	.align 32
+	.type	options.0.1570, @object
+	.size	options.0.1570, 32
+options.0.1570:
+	.long	68
+	.long	511
+	.long	0
+	.long	0
+	.long	0
+	.long	1
+	.long	0
+	.long	1
+	.align 4
+.LC0:
+	.long	1102053376
+	.align 8
+.LC1:
+	.long	0
+	.long	1077968896
+	.align 4
+.LC2:
+	.long	1073741824
+	.align 8
+.LC3:
+	.long	0
+	.long	1074266112
+	.text
+.Letext0:
+	.section	.debug_info,"",@progbits
+.Ldebug_info0:
+#if 0
+	.long	0x247	# Length of Compilation Unit Info
+#else
+	.long	.Ldebuginfo_end - .Ldebug_info1	# Length of Compilation Unit Info
+.Ldebug_info1:
+#endif
+	.value	0x4	# DWARF version number
+	.long	.Ldebug_abbrev0	# Offset Into Abbrev. Section
+	.byte	0x8	# Pointer Size (in bytes)
+	.uleb128 0x1	# (DIE (0xb) DW_TAG_compile_unit)
+	.long	.LASF13	# DW_AT_producer: "GNU Fortran 4.6.3 plus hand hackery"
+	.byte	0xe	# DW_AT_language
+	.byte	0x2	# DW_AT_identifier_case
+	.long	.LASF14	# DW_AT_name: "../gdb.fortran/common-block.f90"
+	.long	.LASF15	# DW_AT_comp_dir: "gdb.dwarf2"
+	.quad	.Ltext0	# DW_AT_low_pc
+	.quad	.Letext0	# DW_AT_high_pc
+	.long	.Ldebug_line0	# DW_AT_stmt_list
+	.uleb128 0x2	# (DIE (0x2e) DW_TAG_subprogram)
+			# DW_AT_external
+	.ascii "in\0"	# DW_AT_name
+	.byte	0x1	# DW_AT_decl_file (../gdb.fortran/common-block.f90)
+	.byte	0x15	# DW_AT_decl_line
+	.ascii "in_\0"	# DW_AT_linkage_name
+	.quad	.LFB0	# DW_AT_low_pc
+	.quad	.LFE0	# DW_AT_high_pc
+	.uleb128 0x1	# DW_AT_frame_base
+	.byte	0x9c	# DW_OP_call_frame_cfa
+			# DW_AT_GNU_all_tail_call_sites
+	.long	0x11a	# DW_AT_sibling
+	.uleb128 0x3	# (DIE (0x4e) DW_TAG_common_block)
+	.long	.LASF0	# DW_AT_name: "fo_o"
+	.byte	0x1	# DW_AT_decl_file (../gdb.fortran/common-block.f90)
+	.byte	0x1f	# DW_AT_decl_line
+	.long	.LASF8	# DW_AT_linkage_name: "fo_o_"
+	.uleb128 0x9	# DW_AT_location
+	.byte	0x3	# DW_OP_addr
+	.quad	fo_o_
+	.long	0xa5	# DW_AT_sibling
+#if 0
+	.uleb128 0x4	# (DIE (0x67) DW_TAG_variable)
+#else
+	.uleb128 0x10	# (DIE (0x1bb) DW_TAG_variable)
+#endif
+	.ascii "ix\0"	# DW_AT_name
+	.byte	0x1	# DW_AT_decl_file (../gdb.fortran/common-block.f90)
+	.byte	0x17	# DW_AT_decl_line
+	.long	0x11a	# DW_AT_type
+			# DW_AT_external
+#if 0
+	.uleb128 0x9	# DW_AT_location
+	.byte	0x3	# DW_OP_addr
+	.quad	fo_o_
+#else
+	.uleb128 0x9	# DW_AT_data_member_location
+			# (size chosen to avoid renumbering all DIEs)
+	.byte	0x8	# DW_OP_const1u
+	.byte	0x0
+	.byte	0x96	# DW_OP_nop
+	.byte	0x96	# DW_OP_nop
+	.byte	0x96	# DW_OP_nop
+	.byte	0x96	# DW_OP_nop
+	.byte	0x96	# DW_OP_nop
+	.byte	0x96	# DW_OP_nop
+	.byte	0x96	# DW_OP_nop
+#endif
+	.uleb128 0x4	# (DIE (0x7b) DW_TAG_variable)
+	.ascii "iy2\0"	# DW_AT_name
+	.byte	0x1	# DW_AT_decl_file (../gdb.fortran/common-block.f90)
+	.byte	0x18	# DW_AT_decl_line
+	.long	0x121	# DW_AT_type
+			# DW_AT_external
+	.uleb128 0x9	# DW_AT_location
+	.byte	0x3	# DW_OP_addr
+	.quad	fo_o_+4
+	.uleb128 0x4	# (DIE (0x90) DW_TAG_variable)
+	.ascii "iz\0"	# DW_AT_name
+	.byte	0x1	# DW_AT_decl_file (../gdb.fortran/common-block.f90)
+	.byte	0x19	# DW_AT_decl_line
+	.long	0x128	# DW_AT_type
+			# DW_AT_external
+	.uleb128 0x9	# DW_AT_location
+	.byte	0x3	# DW_OP_addr
+	.quad	fo_o_+8
+	.byte	0	# end of children of DIE 0x4e
+	.uleb128 0x5	# (DIE (0xa5) DW_TAG_common_block)
+	.ascii "foo\0"	# DW_AT_name
+	.byte	0x1	# DW_AT_decl_file (../gdb.fortran/common-block.f90)
+	.byte	0x20	# DW_AT_decl_line
+	.long	.LASF16	# DW_AT_linkage_name: "foo_"
+	.uleb128 0x9	# DW_AT_location
+	.byte	0x3	# DW_OP_addr
+	.quad	foo_
+	.long	0xfe	# DW_AT_sibling
+	.uleb128 0x6	# (DIE (0xbe) DW_TAG_variable)
+	.long	.LASF1	# DW_AT_name: "ix_x"
+	.byte	0x1	# DW_AT_decl_file (../gdb.fortran/common-block.f90)
+	.byte	0x1b	# DW_AT_decl_line
+	.long	0x11a	# DW_AT_type
+			# DW_AT_external
+	.uleb128 0x9	# DW_AT_location
+	.byte	0x3	# DW_OP_addr
+	.quad	foo_
+	.uleb128 0x6	# (DIE (0xd3) DW_TAG_variable)
+	.long	.LASF2	# DW_AT_name: "iy_y"
+	.byte	0x1	# DW_AT_decl_file (../gdb.fortran/common-block.f90)
+	.byte	0x1c	# DW_AT_decl_line
+	.long	0x121	# DW_AT_type
+			# DW_AT_external
+	.uleb128 0x9	# DW_AT_location
+	.byte	0x3	# DW_OP_addr
+	.quad	foo_+4
+	.uleb128 0x6	# (DIE (0xe8) DW_TAG_variable)
+	.long	.LASF3	# DW_AT_name: "iz_z2"
+	.byte	0x1	# DW_AT_decl_file (../gdb.fortran/common-block.f90)
+	.byte	0x1d	# DW_AT_decl_line
+	.long	0x128	# DW_AT_type
+			# DW_AT_external
+	.uleb128 0x9	# DW_AT_location
+	.byte	0x3	# DW_OP_addr
+	.quad	foo_+8
+	.byte	0	# end of children of DIE 0xa5
+	.uleb128 0x7	# (DIE (0xfe) DW_TAG_variable)
+	.ascii "iy\0"	# DW_AT_name
+	.byte	0x1	# DW_AT_decl_file (../gdb.fortran/common-block.f90)
+	.byte	0x22	# DW_AT_decl_line
+	.long	0x11a	# DW_AT_type
+	.uleb128 0x2	# DW_AT_location
+	.byte	0x91	# DW_OP_fbreg
+	.sleb128 -20
+	.uleb128 0x8	# (DIE (0x10b) DW_TAG_variable)
+	.long	.LASF4	# DW_AT_name: "iz_z"
+	.byte	0x1	# DW_AT_decl_file (../gdb.fortran/common-block.f90)
+	.byte	0x23	# DW_AT_decl_line
+	.long	0x11a	# DW_AT_type
+	.uleb128 0x2	# DW_AT_location
+	.byte	0x91	# DW_OP_fbreg
+	.sleb128 -24
+	.byte	0	# end of children of DIE 0x2e
+	.uleb128 0x9	# (DIE (0x11a) DW_TAG_base_type)
+	.byte	0x4	# DW_AT_byte_size
+	.byte	0x5	# DW_AT_encoding
+	.long	.LASF5	# DW_AT_name: "integer(kind=4)"
+	.uleb128 0x9	# (DIE (0x121) DW_TAG_base_type)
+	.byte	0x4	# DW_AT_byte_size
+	.byte	0x4	# DW_AT_encoding
+	.long	.LASF6	# DW_AT_name: "real(kind=4)"
+	.uleb128 0x9	# (DIE (0x128) DW_TAG_base_type)
+	.byte	0x8	# DW_AT_byte_size
+	.byte	0x4	# DW_AT_encoding
+	.long	.LASF7	# DW_AT_name: "real(kind=8)"
+	.uleb128 0xa	# (DIE (0x12f) DW_TAG_subprogram)
+	.long	.LASF17	# DW_AT_name: "common_test"
+	.byte	0x1	# DW_AT_decl_file (../gdb.fortran/common-block.f90)
+	.byte	0x2c	# DW_AT_decl_line
+	.quad	.LFB1	# DW_AT_low_pc
+	.quad	.LFE1	# DW_AT_high_pc
+	.uleb128 0x1	# DW_AT_frame_base
+	.byte	0x9c	# DW_OP_call_frame_cfa
+			# DW_AT_GNU_all_tail_call_sites
+			# DW_AT_main_subprogram
+	.byte	0x2	# DW_AT_calling_convention
+	.long	0x1f9	# DW_AT_sibling
+	.uleb128 0x3	# (DIE (0x14d) DW_TAG_common_block)
+	.long	.LASF0	# DW_AT_name: "fo_o"
+	.byte	0x1	# DW_AT_decl_file (../gdb.fortran/common-block.f90)
+	.byte	0x1f	# DW_AT_decl_line
+	.long	.LASF8	# DW_AT_linkage_name: "fo_o_"
+	.uleb128 0x9	# DW_AT_location
+	.byte	0x3	# DW_OP_addr
+	.quad	fo_o_
+	.long	0x1a6	# DW_AT_sibling
+	.uleb128 0x6	# (DIE (0x166) DW_TAG_variable)
+	.long	.LASF1	# DW_AT_name: "ix_x"
+	.byte	0x1	# DW_AT_decl_file (../gdb.fortran/common-block.f90)
+	.byte	0x32	# DW_AT_decl_line
+	.long	0x11a	# DW_AT_type
+			# DW_AT_external
+	.uleb128 0x9	# DW_AT_location
+	.byte	0x3	# DW_OP_addr
+	.quad	fo_o_
+	.uleb128 0x6	# (DIE (0x17b) DW_TAG_variable)
+	.long	.LASF2	# DW_AT_name: "iy_y"
+	.byte	0x1	# DW_AT_decl_file (../gdb.fortran/common-block.f90)
+	.byte	0x33	# DW_AT_decl_line
+	.long	0x121	# DW_AT_type
+			# DW_AT_external
+	.uleb128 0x9	# DW_AT_location
+	.byte	0x3	# DW_OP_addr
+	.quad	fo_o_+4
+	.uleb128 0x6	# (DIE (0x190) DW_TAG_variable)
+	.long	.LASF4	# DW_AT_name: "iz_z"
+	.byte	0x1	# DW_AT_decl_file (../gdb.fortran/common-block.f90)
+	.byte	0x34	# DW_AT_decl_line
+	.long	0x128	# DW_AT_type
+			# DW_AT_external
+	.uleb128 0x9	# DW_AT_location
+	.byte	0x3	# DW_OP_addr
+	.quad	fo_o_+8
+	.byte	0	# end of children of DIE 0x14d
+	.uleb128 0xb	# (DIE (0x1a6) DW_TAG_common_block)
+	.ascii "foo\0"	# DW_AT_name
+	.byte	0x1	# DW_AT_decl_file (../gdb.fortran/common-block.f90)
+	.byte	0x20	# DW_AT_decl_line
+	.long	.LASF16	# DW_AT_linkage_name: "foo_"
+	.uleb128 0x9	# DW_AT_location
+	.byte	0x3	# DW_OP_addr
+	.quad	foo_
+#if 0
+	.uleb128 0x4	# (DIE (0x1bb) DW_TAG_variable)
+#else
+	.uleb128 0x10	# (DIE (0x1bb) DW_TAG_variable)
+#endif
+	.ascii "ix\0"	# DW_AT_name
+	.byte	0x1	# DW_AT_decl_file (../gdb.fortran/common-block.f90)
+	.byte	0x2e	# DW_AT_decl_line
+	.long	0x11a	# DW_AT_type
+			# DW_AT_external
+#if 0
+	.uleb128 0x9	# DW_AT_location
+	.byte	0x3	# DW_OP_addr
+	.quad	foo_
+#else
+	.uleb128 0x9	# DW_AT_data_member_location
+			# (size chosen to avoid renumbering all DIEs)
+	.byte	0x8	# DW_OP_const1u
+	.byte	0x0
+	.byte	0x96	# DW_OP_nop
+	.byte	0x96	# DW_OP_nop
+	.byte	0x96	# DW_OP_nop
+	.byte	0x96	# DW_OP_nop
+	.byte	0x96	# DW_OP_nop
+	.byte	0x96	# DW_OP_nop
+	.byte	0x96	# DW_OP_nop
+#endif
+	.uleb128 0x4	# (DIE (0x1cf) DW_TAG_variable)
+	.ascii "iy\0"	# DW_AT_name
+	.byte	0x1	# DW_AT_decl_file (../gdb.fortran/common-block.f90)
+	.byte	0x2f	# DW_AT_decl_line
+	.long	0x121	# DW_AT_type
+			# DW_AT_external
+	.uleb128 0x9	# DW_AT_location
+	.byte	0x3	# DW_OP_addr
+	.quad	foo_+4
+	.uleb128 0x4	# (DIE (0x1e3) DW_TAG_variable)
+	.ascii "iz\0"	# DW_AT_name
+	.byte	0x1	# DW_AT_decl_file (../gdb.fortran/common-block.f90)
+	.byte	0x30	# DW_AT_decl_line
+	.long	0x128	# DW_AT_type
+			# DW_AT_external
+	.uleb128 0x9	# DW_AT_location
+	.byte	0x3	# DW_OP_addr
+	.quad	foo_+8
+	.byte	0	# end of children of DIE 0x1a6
+	.byte	0	# end of children of DIE 0x12f
+	.uleb128 0xc	# (DIE (0x1f9) DW_TAG_subprogram)
+			# DW_AT_external
+	.long	.LASF9	# DW_AT_name: "main"
+	.byte	0x1	# DW_AT_decl_file (../gdb.fortran/common-block.f90)
+	.byte	0x43	# DW_AT_decl_line
+	.long	0x11a	# DW_AT_type
+	.quad	.LFB2	# DW_AT_low_pc
+	.quad	.LFE2	# DW_AT_high_pc
+	.uleb128 0x1	# DW_AT_frame_base
+	.byte	0x9c	# DW_OP_call_frame_cfa
+			# DW_AT_GNU_all_tail_call_sites
+	.long	0x238	# DW_AT_sibling
+	.uleb128 0xd	# (DIE (0x21a) DW_TAG_formal_parameter)
+	.long	.LASF10	# DW_AT_name: "argc"
+	.byte	0x1	# DW_AT_decl_file (../gdb.fortran/common-block.f90)
+	.byte	0x43	# DW_AT_decl_line
+	.long	0x238	# DW_AT_type
+	.uleb128 0x2	# DW_AT_location
+	.byte	0x91	# DW_OP_fbreg
+	.sleb128 -20
+	.uleb128 0xd	# (DIE (0x228) DW_TAG_formal_parameter)
+	.long	.LASF11	# DW_AT_name: "argv"
+	.byte	0x1	# DW_AT_decl_file (../gdb.fortran/common-block.f90)
+	.byte	0x43	# DW_AT_decl_line
+	.long	0x23d	# DW_AT_type
+	.uleb128 0x3	# DW_AT_location
+	.byte	0x91	# DW_OP_fbreg
+	.sleb128 -32
+	.byte	0x6	# DW_OP_deref
+	.byte	0	# end of children of DIE 0x1f9
+	.uleb128 0xe	# (DIE (0x238) DW_TAG_const_type)
+	.long	0x11a	# DW_AT_type
+	.uleb128 0xf	# (DIE (0x23d) DW_TAG_pointer_type)
+	.byte	0x8	# DW_AT_byte_size
+	.long	0x243	# DW_AT_type
+	.uleb128 0x9	# (DIE (0x243) DW_TAG_base_type)
+	.byte	0x1	# DW_AT_byte_size
+	.byte	0x8	# DW_AT_encoding
+	.long	.LASF12	# DW_AT_name: "character(kind=1)"
+	.byte	0	# end of children of DIE 0xb
+#if 0
+#else
+.Ldebuginfo_end:
+#endif
+	.section	.debug_abbrev,"",@progbits
+.Ldebug_abbrev0:
+	.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 0x42	# (DW_AT_identifier_case)
+	.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 0x17	# (DW_FORM_sec_offset)
+	.byte	0
+	.byte	0
+	.uleb128 0x2	# (abbrev code)
+	.uleb128 0x2e	# (TAG: DW_TAG_subprogram)
+	.byte	0x1	# DW_children_yes
+	.uleb128 0x3f	# (DW_AT_external)
+	.uleb128 0x19	# (DW_FORM_flag_present)
+	.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 0x6e	# (DW_AT_linkage_name)
+	.uleb128 0x8	# (DW_FORM_string)
+	.uleb128 0x11	# (DW_AT_low_pc)
+	.uleb128 0x1	# (DW_FORM_addr)
+	.uleb128 0x12	# (DW_AT_high_pc)
+	.uleb128 0x1	# (DW_FORM_addr)
+	.uleb128 0x40	# (DW_AT_frame_base)
+	.uleb128 0x18	# (DW_FORM_exprloc)
+	.uleb128 0x2116	# (DW_AT_GNU_all_tail_call_sites)
+	.uleb128 0x19	# (DW_FORM_flag_present)
+	.uleb128 0x1	# (DW_AT_sibling)
+	.uleb128 0x13	# (DW_FORM_ref4)
+	.byte	0
+	.byte	0
+	.uleb128 0x3	# (abbrev code)
+	.uleb128 0x1a	# (TAG: DW_TAG_common_block)
+	.byte	0x1	# DW_children_yes
+	.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 0x6e	# (DW_AT_linkage_name)
+	.uleb128 0xe	# (DW_FORM_strp)
+	.uleb128 0x2	# (DW_AT_location)
+	.uleb128 0x18	# (DW_FORM_exprloc)
+	.uleb128 0x1	# (DW_AT_sibling)
+	.uleb128 0x13	# (DW_FORM_ref4)
+	.byte	0
+	.byte	0
+	.uleb128 0x4	# (abbrev code)
+	.uleb128 0x34	# (TAG: DW_TAG_variable)
+	.byte	0	# 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 0x19	# (DW_FORM_flag_present)
+	.uleb128 0x2	# (DW_AT_location)
+	.uleb128 0x18	# (DW_FORM_exprloc)
+	.byte	0
+	.byte	0
+	.uleb128 0x5	# (abbrev code)
+	.uleb128 0x1a	# (TAG: DW_TAG_common_block)
+	.byte	0x1	# DW_children_yes
+	.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 0x6e	# (DW_AT_linkage_name)
+	.uleb128 0xe	# (DW_FORM_strp)
+	.uleb128 0x2	# (DW_AT_location)
+	.uleb128 0x18	# (DW_FORM_exprloc)
+	.uleb128 0x1	# (DW_AT_sibling)
+	.uleb128 0x13	# (DW_FORM_ref4)
+	.byte	0
+	.byte	0
+	.uleb128 0x6	# (abbrev code)
+	.uleb128 0x34	# (TAG: DW_TAG_variable)
+	.byte	0	# 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 0x3f	# (DW_AT_external)
+	.uleb128 0x19	# (DW_FORM_flag_present)
+	.uleb128 0x2	# (DW_AT_location)
+	.uleb128 0x18	# (DW_FORM_exprloc)
+	.byte	0
+	.byte	0
+	.uleb128 0x7	# (abbrev code)
+	.uleb128 0x34	# (TAG: DW_TAG_variable)
+	.byte	0	# 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 0x2	# (DW_AT_location)
+	.uleb128 0x18	# (DW_FORM_exprloc)
+	.byte	0
+	.byte	0
+	.uleb128 0x8	# (abbrev code)
+	.uleb128 0x34	# (TAG: DW_TAG_variable)
+	.byte	0	# 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 0x2	# (DW_AT_location)
+	.uleb128 0x18	# (DW_FORM_exprloc)
+	.byte	0
+	.byte	0
+	.uleb128 0x9	# (abbrev code)
+	.uleb128 0x24	# (TAG: DW_TAG_base_type)
+	.byte	0	# 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 0xe	# (DW_FORM_strp)
+	.byte	0
+	.byte	0
+	.uleb128 0xa	# (abbrev code)
+	.uleb128 0x2e	# (TAG: DW_TAG_subprogram)
+	.byte	0x1	# DW_children_yes
+	.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 0x11	# (DW_AT_low_pc)
+	.uleb128 0x1	# (DW_FORM_addr)
+	.uleb128 0x12	# (DW_AT_high_pc)
+	.uleb128 0x1	# (DW_FORM_addr)
+	.uleb128 0x40	# (DW_AT_frame_base)
+	.uleb128 0x18	# (DW_FORM_exprloc)
+	.uleb128 0x2116	# (DW_AT_GNU_all_tail_call_sites)
+	.uleb128 0x19	# (DW_FORM_flag_present)
+	.uleb128 0x6a	# (DW_AT_main_subprogram)
+	.uleb128 0x19	# (DW_FORM_flag_present)
+	.uleb128 0x36	# (DW_AT_calling_convention)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x1	# (DW_AT_sibling)
+	.uleb128 0x13	# (DW_FORM_ref4)
+	.byte	0
+	.byte	0
+	.uleb128 0xb	# (abbrev code)
+	.uleb128 0x1a	# (TAG: DW_TAG_common_block)
+	.byte	0x1	# DW_children_yes
+	.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 0x6e	# (DW_AT_linkage_name)
+	.uleb128 0xe	# (DW_FORM_strp)
+	.uleb128 0x2	# (DW_AT_location)
+	.uleb128 0x18	# (DW_FORM_exprloc)
+	.byte	0
+	.byte	0
+	.uleb128 0xc	# (abbrev code)
+	.uleb128 0x2e	# (TAG: DW_TAG_subprogram)
+	.byte	0x1	# DW_children_yes
+	.uleb128 0x3f	# (DW_AT_external)
+	.uleb128 0x19	# (DW_FORM_flag_present)
+	.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 0x11	# (DW_AT_low_pc)
+	.uleb128 0x1	# (DW_FORM_addr)
+	.uleb128 0x12	# (DW_AT_high_pc)
+	.uleb128 0x1	# (DW_FORM_addr)
+	.uleb128 0x40	# (DW_AT_frame_base)
+	.uleb128 0x18	# (DW_FORM_exprloc)
+	.uleb128 0x2116	# (DW_AT_GNU_all_tail_call_sites)
+	.uleb128 0x19	# (DW_FORM_flag_present)
+	.uleb128 0x1	# (DW_AT_sibling)
+	.uleb128 0x13	# (DW_FORM_ref4)
+	.byte	0
+	.byte	0
+	.uleb128 0xd	# (abbrev code)
+	.uleb128 0x5	# (TAG: DW_TAG_formal_parameter)
+	.byte	0	# 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 0x2	# (DW_AT_location)
+	.uleb128 0x18	# (DW_FORM_exprloc)
+	.byte	0
+	.byte	0
+	.uleb128 0xe	# (abbrev code)
+	.uleb128 0x26	# (TAG: DW_TAG_const_type)
+	.byte	0	# DW_children_no
+	.uleb128 0x49	# (DW_AT_type)
+	.uleb128 0x13	# (DW_FORM_ref4)
+	.byte	0
+	.byte	0
+	.uleb128 0xf	# (abbrev code)
+	.uleb128 0xf	# (TAG: DW_TAG_pointer_type)
+	.byte	0	# 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	0
+	.byte	0
+#if 0
+#else
+	.uleb128 0x10	# (abbrev code)
+	.uleb128 0x34	# (TAG: DW_TAG_variable)
+	.byte	0	# 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 0x19	# (DW_FORM_flag_present)
+	.uleb128 0x38	# (DW_AT_data_member_location)
+	.uleb128 0x18	# (DW_FORM_exprloc)
+	.byte	0
+	.byte	0
+#endif
+	.byte	0
+	.section	.debug_aranges,"",@progbits
+	.long	0x2c	# Length of Address Ranges Info
+	.value	0x2	# DWARF Version
+	.long	.Ldebug_info0	# Offset of Compilation Unit Info
+	.byte	0x8	# Size of Address
+	.byte	0	# Size of Segment Descriptor
+	.value	0	# Pad to 16 byte boundary
+	.value	0
+	.quad	.Ltext0	# Address
+	.quad	.Letext0-.Ltext0	# Length
+	.quad	0
+	.quad	0
+	.section	.debug_line,"",@progbits
+.Ldebug_line0:
+	.section	.debug_str,"MS",@progbits,1
+.LASF0:
+	.string	"fo_o"
+.LASF8:
+	.string	"fo_o_"
+.LASF3:
+	.string	"iz_z2"
+.LASF1:
+	.string	"ix_x"
+.LASF9:
+	.string	"main"
+.LASF4:
+	.string	"iz_z"
+.LASF13:
+	.string	"GNU Fortran 4.6.3 plus hand hackery"
+.LASF16:
+	.string	"foo_"
+.LASF7:
+	.string	"real(kind=8)"
+.LASF5:
+	.string	"integer(kind=4)"
+.LASF17:
+	.string	"common_test"
+.LASF12:
+	.string	"character(kind=1)"
+.LASF14:
+	.string	"../gdb.fortran/common-block.f90"
+.LASF10:
+	.string	"argc"
+.LASF2:
+	.string	"iy_y"
+.LASF11:
+	.string	"argv"
+.LASF15:
+	.string	"gdb.dwarf2"
+.LASF6:
+	.string	"real(kind=4)"
+	.ident	"GCC: (GNU) 4.6.3 20120306 (Red Hat 4.6.3-2)"
+	.section	.note.GNU-stack,"",@progbits
diff --git a/gdb/testsuite/gdb.dwarf2/dw2-common-block.exp b/gdb/testsuite/gdb.dwarf2/dw2-common-block.exp
new file mode 100644
index 0000000..a1914ee
--- /dev/null
+++ b/gdb/testsuite/gdb.dwarf2/dw2-common-block.exp
@@ -0,0 +1,50 @@
+# Copyright 2012 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/>.
+
+load_lib dwarf.exp
+
+# This test can only be run on targets which support DWARF-2 and use gas.
+if ![dwarf2_support] {
+    return 0  
+}
+
+# This test can only be run on x86-64 targets.
+if {![istarget x86_64-*] || ![is_lp64_target]} {
+    return 0
+}
+
+# It requires fortran.
+if {[skip_fortran_tests]} {
+    return 0
+}
+
+standard_testfile .S
+
+if { [prepare_for_testing "${testfile}.exp" "${testfile}" $srcfile \
+	  {nodebug f90}] } {
+    return -1
+}
+
+if ![runto MAIN__] then {
+    perror "couldn't run to breakpoint MAIN__"
+    continue
+}
+
+gdb_breakpoint [gdb_get_line_number "stop-here-out" \
+		    ../gdb.fortran/common-block.f90]
+gdb_continue_to_breakpoint "stop-here-out"
+
+gdb_test "p ix" " = 1" "p ix out"
+gdb_test "p iy" " = 2" "p iy out"
-- 
1.7.7.6

Re: [3/3] RFC - optional patch to restore DW_AT_data_member_location

[Tom Tromey]

>>>>> "Tom" == Tom Tromey <tromey@redhat.com> writes:

Tom> This patch reimplements DW_AT_data_member_location for variables
Tom> appearing in a Fortran common block.

Tom> Here's the refreshed patch.
Tom> I believe I've addressed all the comments.
Tom> Regtested on x86-64 F16.

I'm going to check this in shortly.

Tom