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[PATCH] btrace, frame: fix crash in get_frame_type
- From: Markus Metzger <markus dot t dot metzger at intel dot com>
- To: palves at redhat dot com
- Cc: gdb-patches at sourceware dot org
- Date: Tue, 26 Jan 2016 18:08:52 +0100
- Subject: [PATCH] btrace, frame: fix crash in get_frame_type
- Authentication-results: sourceware.org; auth=none
In skip_artificial_frames we repeatedly call get_prev_frame_always until we get
a non-inline and non-tailcall frame assuming that there must be such a frame
eventually.
For record targets, however, we may have a frame chain that consists only of
inline or tailcall frames.
This leads to a crash in get_frame_type when we dereference a NULL frame
pointer.
The comment on skip_artificial_frames says
/* Given FRAME, return the enclosing frame as found in real frames read-in from
inferior memory. Skip any previous frames which were made up by GDB.
Return the original frame if no immediate previous frames exist. */
That last part, "return the original frame if no immediate previous frames
exist", is missing. I added that.
I found two other places where get_frame_type is called in a similar setup to
skip tailcall frames:
- in infcmd.c to implement the "finish" command
- in frame.c's pop_frame which is used by the "return" command
In both cases I added a NULL pointer check for the frame and throw an error in
case we don't find a non-tailcall frame.
In infcmd I further moved the tailcall-frame-chasing loop to the
forward-stepping case since we don't need a frame for reverse execution and we
don't want to fail because of that. Reverse-finish does make sense for a
tailcall frame.
All 3 functions I modified are covered by the regression test included in this
patch. I believe I covered all get_frame_type-in-a-tailcall-chasing-loop cases
but I'm not entirely sure. If you find one I missed, please point it out to me.
2016-01-26 Markus Metzger <markus.t.metzger@intel.com>
gdb/
* frame.c (skip_artificial_frames): Return original frame if only
artificial frames are found.
(frame_pop): Add an error if only tailcall frames are found.
* infcmd.c (finish_command): Move tailcall-chasing loop into forward-
execution case. Add an error if only tailcall frames are found.
testsuite/
* gdb.btrace/tailcall-only.exp: New.
* gdb.btrace/tailcall-only.c: New.
* gdb.btrace/x86_64-tailcall-only.S: New.
* gdb.btrace/i686-tailcall-only.S: New.
---
gdb/frame.c | 26 +-
gdb/infcmd.c | 17 +-
gdb/testsuite/gdb.btrace/i686-tailcall-only.S | 447 ++++++++++++++++++++++++
gdb/testsuite/gdb.btrace/tailcall-only.c | 53 +++
gdb/testsuite/gdb.btrace/tailcall-only.exp | 93 +++++
gdb/testsuite/gdb.btrace/x86_64-tailcall-only.S | 446 +++++++++++++++++++++++
6 files changed, 1070 insertions(+), 12 deletions(-)
create mode 100644 gdb/testsuite/gdb.btrace/i686-tailcall-only.S
create mode 100644 gdb/testsuite/gdb.btrace/tailcall-only.c
create mode 100644 gdb/testsuite/gdb.btrace/tailcall-only.exp
create mode 100644 gdb/testsuite/gdb.btrace/x86_64-tailcall-only.S
diff --git a/gdb/frame.c b/gdb/frame.c
index 48c9b33..36693f3 100644
--- a/gdb/frame.c
+++ b/gdb/frame.c
@@ -425,16 +425,26 @@ fprint_frame (struct ui_file *file, struct frame_info *fi)
static struct frame_info *
skip_artificial_frames (struct frame_info *frame)
{
+ struct frame_info *orig_frame;
+
+ orig_frame = frame;
+
/* Note we use get_prev_frame_always, and not get_prev_frame. The
latter will truncate the frame chain, leading to this function
unintentionally returning a null_frame_id (e.g., when the user
- sets a backtrace limit). This is safe, because as these frames
- are made up by GDB, there must be a real frame in the chain
- below. */
- while (get_frame_type (frame) == INLINE_FRAME
- || get_frame_type (frame) == TAILCALL_FRAME)
+ sets a backtrace limit).
+
+ Note that for record targets we may get a frame chain that consists
+ only of inline and tailcall frames. We return the original frame in
+ that case. */
+ while (frame != NULL &&
+ (get_frame_type (frame) == INLINE_FRAME
+ || get_frame_type (frame) == TAILCALL_FRAME))
frame = get_prev_frame_always (frame);
+ if (frame == NULL)
+ frame = orig_frame;
+
return frame;
}
@@ -972,9 +982,13 @@ frame_pop (struct frame_info *this_frame)
/* Ignore TAILCALL_FRAME type frames, they were executed already before
entering THISFRAME. */
- while (get_frame_type (prev_frame) == TAILCALL_FRAME)
+ while (prev_frame != NULL && get_frame_type (prev_frame) == TAILCALL_FRAME)
prev_frame = get_prev_frame (prev_frame);
+ /* We cannot pop tailcall frames. */
+ if (prev_frame == NULL)
+ error (_("Cannot pop tailcall frame(s)."));
+
/* Make a copy of all the register values unwound from this frame.
Save them in a scratch buffer so that there isn't a race between
trying to extract the old values from the current regcache while
diff --git a/gdb/infcmd.c b/gdb/infcmd.c
index df13896..7ccd449 100644
--- a/gdb/infcmd.c
+++ b/gdb/infcmd.c
@@ -2000,11 +2000,6 @@ finish_command (char *arg, int from_tty)
return;
}
- /* Ignore TAILCALL_FRAME type frames, they were executed already before
- entering THISFRAME. */
- while (get_frame_type (frame) == TAILCALL_FRAME)
- frame = get_prev_frame (frame);
-
/* Find the function we will return from. */
sm->function = find_pc_function (get_frame_pc (get_selected_frame (NULL)));
@@ -2031,7 +2026,17 @@ finish_command (char *arg, int from_tty)
if (execution_direction == EXEC_REVERSE)
finish_backward (sm);
else
- finish_forward (sm, frame);
+ {
+ /* Ignore TAILCALL_FRAME type frames, they were executed already before
+ entering THISFRAME. */
+ while (frame != NULL && get_frame_type (frame) == TAILCALL_FRAME)
+ frame = get_prev_frame (frame);
+
+ if (frame == NULL)
+ error (_("\"finish\" not meaningful for tailcall frame(s)."));
+
+ finish_forward (sm, frame);
+ }
}
diff --git a/gdb/testsuite/gdb.btrace/i686-tailcall-only.S b/gdb/testsuite/gdb.btrace/i686-tailcall-only.S
new file mode 100644
index 0000000..a89f2f2
--- /dev/null
+++ b/gdb/testsuite/gdb.btrace/i686-tailcall-only.S
@@ -0,0 +1,447 @@
+/* This testcase is part of GDB, the GNU debugger.
+
+ Copyright 2016 Free Software Foundation, Inc.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 3 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program. If not, see <http://www.gnu.org/licenses/>.
+
+
+ This file has been generated using:
+ gcc -m32 -march=i686 -S -O2 -dA -g tailcall-only.c -o i686-tailcall-only.S
+ */
+
+ .file "tailcall-only.c"
+ .text
+.Ltext0:
+ .p2align 4,,15
+ .type bar_1, @function
+bar_1:
+.LFB0:
+ .file 1 "tailcall-only.c"
+ # tailcall-only.c:22
+ .loc 1 22 0
+ .cfi_startproc
+# BLOCK 2 freq:10000 seq:0
+# PRED: ENTRY [100.0%] (FALLTHRU)
+ # tailcall-only.c:24
+ .loc 1 24 0
+ movl $42, %eax
+# SUCC: EXIT [100.0%]
+ ret
+ .cfi_endproc
+.LFE0:
+ .size bar_1, .-bar_1
+ .p2align 4,,15
+ .type bar, @function
+bar:
+.LFB1:
+ # tailcall-only.c:28
+ .loc 1 28 0
+ .cfi_startproc
+# BLOCK 2 freq:10000 seq:0
+# PRED: ENTRY [100.0%] (FALLTHRU)
+ # tailcall-only.c:29
+ .loc 1 29 0
+ jmp bar_1
+# SUCC: EXIT [100.0%] (ABNORMAL,SIBCALL)
+.LVL0:
+ .cfi_endproc
+.LFE1:
+ .size bar, .-bar
+ .p2align 4,,15
+ .type foo_1, @function
+foo_1:
+.LFB2:
+ # tailcall-only.c:34
+ .loc 1 34 0
+ .cfi_startproc
+# BLOCK 2 freq:10000 seq:0
+# PRED: ENTRY [100.0%] (FALLTHRU)
+ # tailcall-only.c:35
+ .loc 1 35 0
+ jmp bar
+# SUCC: EXIT [100.0%] (ABNORMAL,SIBCALL)
+.LVL1:
+ .cfi_endproc
+.LFE2:
+ .size foo_1, .-foo_1
+ .p2align 4,,15
+ .type foo, @function
+foo:
+.LFB3:
+ # tailcall-only.c:40
+ .loc 1 40 0
+ .cfi_startproc
+# BLOCK 2 freq:10000 seq:0
+# PRED: ENTRY [100.0%] (FALLTHRU)
+ # tailcall-only.c:41
+ .loc 1 41 0
+ jmp foo_1
+# SUCC: EXIT [100.0%] (ABNORMAL,SIBCALL)
+.LVL2:
+ .cfi_endproc
+.LFE3:
+ .size foo, .-foo
+ .section .text.startup,"ax",@progbits
+ .p2align 4,,15
+ .globl main
+ .type main, @function
+main:
+.LFB4:
+ # tailcall-only.c:46
+ .loc 1 46 0
+ .cfi_startproc
+# BLOCK 2 freq:10000 seq:0
+# PRED: ENTRY [100.0%] (FALLTHRU)
+ # tailcall-only.c:49
+ .loc 1 49 0
+ call foo
+.LVL3:
+ # tailcall-only.c:50
+ .loc 1 50 0
+ addl $1, %eax
+.LVL4:
+# SUCC: EXIT [100.0%]
+ # tailcall-only.c:53
+ .loc 1 53 0
+ ret
+ .cfi_endproc
+.LFE4:
+ .size main, .-main
+ .text
+.Letext0:
+ .section .debug_info,"",@progbits
+.Ldebug_info0:
+ .long 0xd5 # Length of Compilation Unit Info
+ .value 0x4 # 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 .LASF1 # DW_AT_producer: "GNU C 4.8.3 20140911 (Red Hat 4.8.3-9) -m32 -march=i686 -g -O2"
+ .byte 0x1 # DW_AT_language
+ .long .LASF2 # DW_AT_name: "tailcall-only.c"
+ .long .LASF3 # DW_AT_comp_dir: ""
+ .long .Ldebug_ranges0+0 # DW_AT_ranges
+ .long 0 # DW_AT_low_pc
+ .long .Ldebug_line0 # DW_AT_stmt_list
+ .uleb128 0x2 # (DIE (0x25) DW_TAG_subprogram)
+ .long .LASF4 # DW_AT_name: "bar_1"
+ .byte 0x1 # DW_AT_decl_file (tailcall-only.c)
+ .byte 0x15 # DW_AT_decl_line
+ # DW_AT_prototyped
+ .long 0x3a # DW_AT_type
+ .long .LFB0 # DW_AT_low_pc
+ .long .LFE0-.LFB0 # DW_AT_high_pc
+ .uleb128 0x1 # DW_AT_frame_base
+ .byte 0x9c # DW_OP_call_frame_cfa
+ # DW_AT_GNU_all_call_sites
+ .uleb128 0x3 # (DIE (0x3a) DW_TAG_base_type)
+ .byte 0x4 # DW_AT_byte_size
+ .byte 0x5 # DW_AT_encoding
+ .ascii "int\0" # DW_AT_name
+ .uleb128 0x4 # (DIE (0x41) DW_TAG_subprogram)
+ .ascii "bar\0" # DW_AT_name
+ .byte 0x1 # DW_AT_decl_file (tailcall-only.c)
+ .byte 0x1b # DW_AT_decl_line
+ # DW_AT_prototyped
+ .long 0x3a # DW_AT_type
+ .long .LFB1 # DW_AT_low_pc
+ .long .LFE1-.LFB1 # DW_AT_high_pc
+ .uleb128 0x1 # DW_AT_frame_base
+ .byte 0x9c # DW_OP_call_frame_cfa
+ # DW_AT_GNU_all_call_sites
+ .long 0x64 # DW_AT_sibling
+ .uleb128 0x5 # (DIE (0x5a) DW_TAG_GNU_call_site)
+ .long .LVL0 # DW_AT_low_pc
+ # DW_AT_GNU_tail_call
+ .long 0x25 # DW_AT_abstract_origin
+ .byte 0 # end of children of DIE 0x41
+ .uleb128 0x6 # (DIE (0x64) DW_TAG_subprogram)
+ .long .LASF0 # DW_AT_name: "foo_1"
+ .byte 0x1 # DW_AT_decl_file (tailcall-only.c)
+ .byte 0x21 # DW_AT_decl_line
+ # DW_AT_prototyped
+ .long 0x3a # DW_AT_type
+ .long .LFB2 # DW_AT_low_pc
+ .long .LFE2-.LFB2 # DW_AT_high_pc
+ .uleb128 0x1 # DW_AT_frame_base
+ .byte 0x9c # DW_OP_call_frame_cfa
+ # DW_AT_GNU_all_call_sites
+ .long 0x87 # DW_AT_sibling
+ .uleb128 0x5 # (DIE (0x7d) DW_TAG_GNU_call_site)
+ .long .LVL1 # DW_AT_low_pc
+ # DW_AT_GNU_tail_call
+ .long 0x41 # DW_AT_abstract_origin
+ .byte 0 # end of children of DIE 0x64
+ .uleb128 0x4 # (DIE (0x87) DW_TAG_subprogram)
+ .ascii "foo\0" # DW_AT_name
+ .byte 0x1 # DW_AT_decl_file (tailcall-only.c)
+ .byte 0x27 # DW_AT_decl_line
+ # DW_AT_prototyped
+ .long 0x3a # DW_AT_type
+ .long .LFB3 # DW_AT_low_pc
+ .long .LFE3-.LFB3 # DW_AT_high_pc
+ .uleb128 0x1 # DW_AT_frame_base
+ .byte 0x9c # DW_OP_call_frame_cfa
+ # DW_AT_GNU_all_call_sites
+ .long 0xaa # DW_AT_sibling
+ .uleb128 0x5 # (DIE (0xa0) DW_TAG_GNU_call_site)
+ .long .LVL2 # DW_AT_low_pc
+ # DW_AT_GNU_tail_call
+ .long 0x64 # DW_AT_abstract_origin
+ .byte 0 # end of children of DIE 0x87
+ .uleb128 0x7 # (DIE (0xaa) DW_TAG_subprogram)
+ # DW_AT_external
+ .long .LASF5 # DW_AT_name: "main"
+ .byte 0x1 # DW_AT_decl_file (tailcall-only.c)
+ .byte 0x2d # DW_AT_decl_line
+ # DW_AT_prototyped
+ .long 0x3a # DW_AT_type
+ .long .LFB4 # DW_AT_low_pc
+ .long .LFE4-.LFB4 # DW_AT_high_pc
+ .uleb128 0x1 # DW_AT_frame_base
+ .byte 0x9c # DW_OP_call_frame_cfa
+ # DW_AT_GNU_all_call_sites
+ .uleb128 0x8 # (DIE (0xbf) DW_TAG_variable)
+ .long .LASF6 # DW_AT_name: "answer"
+ .byte 0x1 # DW_AT_decl_file (tailcall-only.c)
+ .byte 0x2f # DW_AT_decl_line
+ .long 0x3a # DW_AT_type
+ .long .LLST0 # DW_AT_location
+ .uleb128 0x9 # (DIE (0xce) DW_TAG_GNU_call_site)
+ .long .LVL3 # DW_AT_low_pc
+ .long 0x87 # DW_AT_abstract_origin
+ .byte 0 # end of children of DIE 0xaa
+ .byte 0 # end of children of DIE 0xb
+ .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 0x3 # (DW_AT_name)
+ .uleb128 0xe # (DW_FORM_strp)
+ .uleb128 0x1b # (DW_AT_comp_dir)
+ .uleb128 0xe # (DW_FORM_strp)
+ .uleb128 0x55 # (DW_AT_ranges)
+ .uleb128 0x17 # (DW_FORM_sec_offset)
+ .uleb128 0x11 # (DW_AT_low_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 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 0x27 # (DW_AT_prototyped)
+ .uleb128 0x19 # (DW_FORM_flag_present)
+ .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 0x6 # (DW_FORM_data4)
+ .uleb128 0x40 # (DW_AT_frame_base)
+ .uleb128 0x18 # (DW_FORM_exprloc)
+ .uleb128 0x2117 # (DW_AT_GNU_all_call_sites)
+ .uleb128 0x19 # (DW_FORM_flag_present)
+ .byte 0
+ .byte 0
+ .uleb128 0x3 # (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 0x8 # (DW_FORM_string)
+ .byte 0
+ .byte 0
+ .uleb128 0x4 # (abbrev code)
+ .uleb128 0x2e # (TAG: DW_TAG_subprogram)
+ .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 0x27 # (DW_AT_prototyped)
+ .uleb128 0x19 # (DW_FORM_flag_present)
+ .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 0x6 # (DW_FORM_data4)
+ .uleb128 0x40 # (DW_AT_frame_base)
+ .uleb128 0x18 # (DW_FORM_exprloc)
+ .uleb128 0x2117 # (DW_AT_GNU_all_call_sites)
+ .uleb128 0x19 # (DW_FORM_flag_present)
+ .uleb128 0x1 # (DW_AT_sibling)
+ .uleb128 0x13 # (DW_FORM_ref4)
+ .byte 0
+ .byte 0
+ .uleb128 0x5 # (abbrev code)
+ .uleb128 0x4109 # (TAG: DW_TAG_GNU_call_site)
+ .byte 0 # DW_children_no
+ .uleb128 0x11 # (DW_AT_low_pc)
+ .uleb128 0x1 # (DW_FORM_addr)
+ .uleb128 0x2115 # (DW_AT_GNU_tail_call)
+ .uleb128 0x19 # (DW_FORM_flag_present)
+ .uleb128 0x31 # (DW_AT_abstract_origin)
+ .uleb128 0x13 # (DW_FORM_ref4)
+ .byte 0
+ .byte 0
+ .uleb128 0x6 # (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 0x27 # (DW_AT_prototyped)
+ .uleb128 0x19 # (DW_FORM_flag_present)
+ .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 0x6 # (DW_FORM_data4)
+ .uleb128 0x40 # (DW_AT_frame_base)
+ .uleb128 0x18 # (DW_FORM_exprloc)
+ .uleb128 0x2117 # (DW_AT_GNU_all_call_sites)
+ .uleb128 0x19 # (DW_FORM_flag_present)
+ .uleb128 0x1 # (DW_AT_sibling)
+ .uleb128 0x13 # (DW_FORM_ref4)
+ .byte 0
+ .byte 0
+ .uleb128 0x7 # (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 0x27 # (DW_AT_prototyped)
+ .uleb128 0x19 # (DW_FORM_flag_present)
+ .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 0x6 # (DW_FORM_data4)
+ .uleb128 0x40 # (DW_AT_frame_base)
+ .uleb128 0x18 # (DW_FORM_exprloc)
+ .uleb128 0x2117 # (DW_AT_GNU_all_call_sites)
+ .uleb128 0x19 # (DW_FORM_flag_present)
+ .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 0x17 # (DW_FORM_sec_offset)
+ .byte 0
+ .byte 0
+ .uleb128 0x9 # (abbrev code)
+ .uleb128 0x4109 # (TAG: DW_TAG_GNU_call_site)
+ .byte 0 # DW_children_no
+ .uleb128 0x11 # (DW_AT_low_pc)
+ .uleb128 0x1 # (DW_FORM_addr)
+ .uleb128 0x31 # (DW_AT_abstract_origin)
+ .uleb128 0x13 # (DW_FORM_ref4)
+ .byte 0
+ .byte 0
+ .byte 0
+ .section .debug_loc,"",@progbits
+.Ldebug_loc0:
+.LLST0:
+ .long .LVL3 # Location list begin address (*.LLST0)
+ .long .LVL4 # Location list end address (*.LLST0)
+ .value 0x3 # Location expression size
+ .byte 0x70 # DW_OP_breg0
+ .sleb128 1
+ .byte 0x9f # DW_OP_stack_value
+ .long .LVL4 # Location list begin address (*.LLST0)
+ .long .LFE4 # Location list end address (*.LLST0)
+ .value 0x1 # Location expression size
+ .byte 0x50 # DW_OP_reg0
+ .long 0 # Location list terminator begin (*.LLST0)
+ .long 0 # Location list terminator end (*.LLST0)
+ .section .debug_aranges,"",@progbits
+ .long 0x24 # Length of Address Ranges Info
+ .value 0x2 # DWARF Version
+ .long .Ldebug_info0 # Offset of Compilation Unit Info
+ .byte 0x4 # Size of Address
+ .byte 0 # Size of Segment Descriptor
+ .value 0 # Pad to 8 byte boundary
+ .value 0
+ .long .Ltext0 # Address
+ .long .Letext0-.Ltext0 # Length
+ .long .LFB4 # Address
+ .long .LFE4-.LFB4 # Length
+ .long 0
+ .long 0
+ .section .debug_ranges,"",@progbits
+.Ldebug_ranges0:
+ .long .Ltext0 # Offset 0
+ .long .Letext0
+ .long .LFB4 # Offset 0x8
+ .long .LFE4
+ .long 0
+ .long 0
+ .section .debug_line,"",@progbits
+.Ldebug_line0:
+ .section .debug_str,"MS",@progbits,1
+.LASF4:
+ .string "bar_1"
+.LASF2:
+ .string "tailcall-only.c"
+.LASF1:
+ .string "GNU C 4.8.3 20140911 (Red Hat 4.8.3-9) -m32 -march=i686 -g -O2"
+.LASF6:
+ .string "answer"
+.LASF5:
+ .string "main"
+.LASF3:
+ .string ""
+.LASF0:
+ .string "foo_1"
+ .ident "GCC: (GNU) 4.8.3 20140911 (Red Hat 4.8.3-9)"
+ .section .note.GNU-stack,"",@progbits
diff --git a/gdb/testsuite/gdb.btrace/tailcall-only.c b/gdb/testsuite/gdb.btrace/tailcall-only.c
new file mode 100644
index 0000000..5913ddc
--- /dev/null
+++ b/gdb/testsuite/gdb.btrace/tailcall-only.c
@@ -0,0 +1,53 @@
+/* This testcase is part of GDB, the GNU debugger.
+
+ Copyright 2016 Free Software Foundation, Inc.
+
+ Contributed by Intel Corp. <markus.t.metzger@intel.com>
+
+ 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/>. */
+
+static __attribute__ ((noinline)) int
+bar_1 (void)
+{
+ return 42;
+}
+
+static __attribute__ ((noinline)) int
+bar (void)
+{
+ return bar_1 ();
+}
+
+static __attribute__ ((noinline)) int
+foo_1 (void)
+{
+ return bar ();
+}
+
+static __attribute__ ((noinline)) int
+foo (void)
+{
+ return foo_1 ();
+}
+
+int
+main (void)
+{
+ int answer;
+
+ answer = foo ();
+ answer += 1;
+
+ return answer;
+}
diff --git a/gdb/testsuite/gdb.btrace/tailcall-only.exp b/gdb/testsuite/gdb.btrace/tailcall-only.exp
new file mode 100644
index 0000000..54a479d
--- /dev/null
+++ b/gdb/testsuite/gdb.btrace/tailcall-only.exp
@@ -0,0 +1,93 @@
+# This testcase is part of GDB, the GNU debugger.
+#
+# Copyright 2016 Free Software Foundation, Inc.
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program. If not, see <http://www.gnu.org/licenses/>.
+#
+#
+# This is a variant of tailcall.exp where the entire trace contains only tail
+# calls. This used to cause a crash in get_frame_type.
+#
+
+# check for btrace support
+if { [skip_btrace_tests] } { return -1 }
+
+# This test requires the compiler to generate a tail call. To guarantee that
+# we always get one, we use an assembly source file.
+#
+# We use different assembly sources based on the target architecture.
+#
+# Luckily, they are similar enough that a single test script can handle
+# both.
+set opts {}
+if [info exists COMPILE] {
+ # make check RUNTESTFLAGS="gdb.btrace/tailcall-only.exp COMPILE=1"
+ standard_testfile tailcall-only.c
+ lappend opts debug optimize=-O2
+} elseif {[istarget "x86_64-*-*"]} {
+ standard_testfile x86_64-tailcall-only.S
+} elseif {[istarget "i?86-*-*"]} {
+ standard_testfile i686-tailcall-only.S
+} else {
+ verbose "Skipping ${testfile}."
+ return
+}
+
+if [prepare_for_testing tailcall-only.exp $testfile $srcfile $opts] {
+ return -1
+}
+if ![runto_main] {
+ return -1
+}
+
+# we want to see the full trace for this test
+gdb_test_no_output "set record function-call-history-size 0"
+
+# trace foo
+gdb_test "step" ".*"
+gdb_test_no_output "record btrace"
+gdb_test "stepi 4" ".*"
+
+# for debugging
+gdb_test "info record" ".*"
+
+# show the branch trace with calls indented
+gdb_test "record function-call-history /c 1" [multi_line \
+ "1\tfoo" \
+ "2\t foo_1" \
+ "3\t bar" \
+ "4\t bar_1"
+ ] "function-call-history"
+
+# We can step
+gdb_test "record goto begin" ".*foo.*"
+gdb_test "stepi" ".*foo_1.*"
+gdb_test "step" ".*bar.*"
+gdb_test "stepi" ".*bar_1.*"
+
+# We can neither finish nor return.
+gdb_test "finish" "\"finish\" not meaningful for tailcall frame.*"
+gdb_test_multiple "return" "return" {
+ -re "Make .* return now.*y or n. $" {
+ send_gdb "y\n"
+ exp_continue
+ }
+ -re "Cannot pop tailcall frame.*$gdb_prompt $" {
+ pass "return"
+ }
+}
+
+# But we can reverse-finish
+gdb_test "reverse-finish" ".*bar.*"
+gdb_test "reverse-step" ".*foo_1.*"
diff --git a/gdb/testsuite/gdb.btrace/x86_64-tailcall-only.S b/gdb/testsuite/gdb.btrace/x86_64-tailcall-only.S
new file mode 100644
index 0000000..710288a
--- /dev/null
+++ b/gdb/testsuite/gdb.btrace/x86_64-tailcall-only.S
@@ -0,0 +1,446 @@
+/* This testcase is part of GDB, the GNU debugger.
+
+ Copyright 2016 Free Software Foundation, Inc.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 3 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program. If not, see <http://www.gnu.org/licenses/>.
+
+
+ This file has been generated using:
+ gcc -S -O2 -dA -g tailcall-only.c -o x86_64-tailcall-only.S */
+
+ .file "tailcall-only.c"
+ .text
+.Ltext0:
+ .p2align 4,,15
+ .type bar_1, @function
+bar_1:
+.LFB0:
+ .file 1 "tailcall-only.c"
+ # tailcall-only.c:22
+ .loc 1 22 0
+ .cfi_startproc
+# BLOCK 2 freq:10000 seq:0
+# PRED: ENTRY [100.0%] (FALLTHRU)
+ # tailcall-only.c:24
+ .loc 1 24 0
+ movl $42, %eax
+# SUCC: EXIT [100.0%]
+ ret
+ .cfi_endproc
+.LFE0:
+ .size bar_1, .-bar_1
+ .p2align 4,,15
+ .type bar, @function
+bar:
+.LFB1:
+ # tailcall-only.c:28
+ .loc 1 28 0
+ .cfi_startproc
+# BLOCK 2 freq:10000 seq:0
+# PRED: ENTRY [100.0%] (FALLTHRU)
+ # tailcall-only.c:29
+ .loc 1 29 0
+ jmp bar_1
+# SUCC: EXIT [100.0%] (ABNORMAL,SIBCALL)
+.LVL0:
+ .cfi_endproc
+.LFE1:
+ .size bar, .-bar
+ .p2align 4,,15
+ .type foo_1, @function
+foo_1:
+.LFB2:
+ # tailcall-only.c:34
+ .loc 1 34 0
+ .cfi_startproc
+# BLOCK 2 freq:10000 seq:0
+# PRED: ENTRY [100.0%] (FALLTHRU)
+ # tailcall-only.c:35
+ .loc 1 35 0
+ jmp bar
+# SUCC: EXIT [100.0%] (ABNORMAL,SIBCALL)
+.LVL1:
+ .cfi_endproc
+.LFE2:
+ .size foo_1, .-foo_1
+ .p2align 4,,15
+ .type foo, @function
+foo:
+.LFB3:
+ # tailcall-only.c:40
+ .loc 1 40 0
+ .cfi_startproc
+# BLOCK 2 freq:10000 seq:0
+# PRED: ENTRY [100.0%] (FALLTHRU)
+ # tailcall-only.c:41
+ .loc 1 41 0
+ jmp foo_1
+# SUCC: EXIT [100.0%] (ABNORMAL,SIBCALL)
+.LVL2:
+ .cfi_endproc
+.LFE3:
+ .size foo, .-foo
+ .section .text.startup,"ax",@progbits
+ .p2align 4,,15
+ .globl main
+ .type main, @function
+main:
+.LFB4:
+ # tailcall-only.c:46
+ .loc 1 46 0
+ .cfi_startproc
+# BLOCK 2 freq:10000 seq:0
+# PRED: ENTRY [100.0%] (FALLTHRU)
+ # tailcall-only.c:49
+ .loc 1 49 0
+ call foo
+.LVL3:
+ # tailcall-only.c:50
+ .loc 1 50 0
+ addl $1, %eax
+.LVL4:
+# SUCC: EXIT [100.0%]
+ # tailcall-only.c:53
+ .loc 1 53 0
+ ret
+ .cfi_endproc
+.LFE4:
+ .size main, .-main
+ .text
+.Letext0:
+ .section .debug_info,"",@progbits
+.Ldebug_info0:
+ .long 0x111 # Length of Compilation Unit Info
+ .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 .LASF1 # DW_AT_producer: "GNU C 4.8.3 20140911 (Red Hat 4.8.3-9) -mtune=generic -march=x86-64 -g -O2"
+ .byte 0x1 # DW_AT_language
+ .long .LASF2 # DW_AT_name: "tailcall-only.c"
+ .long .LASF3 # DW_AT_comp_dir: ""
+ .long .Ldebug_ranges0+0 # DW_AT_ranges
+ .quad 0 # DW_AT_low_pc
+ .long .Ldebug_line0 # DW_AT_stmt_list
+ .uleb128 0x2 # (DIE (0x29) DW_TAG_subprogram)
+ .long .LASF4 # DW_AT_name: "bar_1"
+ .byte 0x1 # DW_AT_decl_file (tailcall-only.c)
+ .byte 0x15 # DW_AT_decl_line
+ # DW_AT_prototyped
+ .long 0x46 # DW_AT_type
+ .quad .LFB0 # DW_AT_low_pc
+ .quad .LFE0-.LFB0 # DW_AT_high_pc
+ .uleb128 0x1 # DW_AT_frame_base
+ .byte 0x9c # DW_OP_call_frame_cfa
+ # DW_AT_GNU_all_call_sites
+ .uleb128 0x3 # (DIE (0x46) DW_TAG_base_type)
+ .byte 0x4 # DW_AT_byte_size
+ .byte 0x5 # DW_AT_encoding
+ .ascii "int\0" # DW_AT_name
+ .uleb128 0x4 # (DIE (0x4d) DW_TAG_subprogram)
+ .ascii "bar\0" # DW_AT_name
+ .byte 0x1 # DW_AT_decl_file (tailcall-only.c)
+ .byte 0x1b # DW_AT_decl_line
+ # DW_AT_prototyped
+ .long 0x46 # DW_AT_type
+ .quad .LFB1 # DW_AT_low_pc
+ .quad .LFE1-.LFB1 # DW_AT_high_pc
+ .uleb128 0x1 # DW_AT_frame_base
+ .byte 0x9c # DW_OP_call_frame_cfa
+ # DW_AT_GNU_all_call_sites
+ .long 0x7c # DW_AT_sibling
+ .uleb128 0x5 # (DIE (0x6e) DW_TAG_GNU_call_site)
+ .quad .LVL0 # DW_AT_low_pc
+ # DW_AT_GNU_tail_call
+ .long 0x29 # DW_AT_abstract_origin
+ .byte 0 # end of children of DIE 0x4d
+ .uleb128 0x6 # (DIE (0x7c) DW_TAG_subprogram)
+ .long .LASF0 # DW_AT_name: "foo_1"
+ .byte 0x1 # DW_AT_decl_file (tailcall-only.c)
+ .byte 0x21 # DW_AT_decl_line
+ # DW_AT_prototyped
+ .long 0x46 # DW_AT_type
+ .quad .LFB2 # DW_AT_low_pc
+ .quad .LFE2-.LFB2 # DW_AT_high_pc
+ .uleb128 0x1 # DW_AT_frame_base
+ .byte 0x9c # DW_OP_call_frame_cfa
+ # DW_AT_GNU_all_call_sites
+ .long 0xab # DW_AT_sibling
+ .uleb128 0x5 # (DIE (0x9d) DW_TAG_GNU_call_site)
+ .quad .LVL1 # DW_AT_low_pc
+ # DW_AT_GNU_tail_call
+ .long 0x4d # DW_AT_abstract_origin
+ .byte 0 # end of children of DIE 0x7c
+ .uleb128 0x4 # (DIE (0xab) DW_TAG_subprogram)
+ .ascii "foo\0" # DW_AT_name
+ .byte 0x1 # DW_AT_decl_file (tailcall-only.c)
+ .byte 0x27 # DW_AT_decl_line
+ # DW_AT_prototyped
+ .long 0x46 # DW_AT_type
+ .quad .LFB3 # DW_AT_low_pc
+ .quad .LFE3-.LFB3 # DW_AT_high_pc
+ .uleb128 0x1 # DW_AT_frame_base
+ .byte 0x9c # DW_OP_call_frame_cfa
+ # DW_AT_GNU_all_call_sites
+ .long 0xda # DW_AT_sibling
+ .uleb128 0x5 # (DIE (0xcc) DW_TAG_GNU_call_site)
+ .quad .LVL2 # DW_AT_low_pc
+ # DW_AT_GNU_tail_call
+ .long 0x7c # DW_AT_abstract_origin
+ .byte 0 # end of children of DIE 0xab
+ .uleb128 0x7 # (DIE (0xda) DW_TAG_subprogram)
+ # DW_AT_external
+ .long .LASF5 # DW_AT_name: "main"
+ .byte 0x1 # DW_AT_decl_file (tailcall-only.c)
+ .byte 0x2d # DW_AT_decl_line
+ # DW_AT_prototyped
+ .long 0x46 # DW_AT_type
+ .quad .LFB4 # DW_AT_low_pc
+ .quad .LFE4-.LFB4 # DW_AT_high_pc
+ .uleb128 0x1 # DW_AT_frame_base
+ .byte 0x9c # DW_OP_call_frame_cfa
+ # DW_AT_GNU_all_call_sites
+ .uleb128 0x8 # (DIE (0xf7) DW_TAG_variable)
+ .long .LASF6 # DW_AT_name: "answer"
+ .byte 0x1 # DW_AT_decl_file (tailcall-only.c)
+ .byte 0x2f # DW_AT_decl_line
+ .long 0x46 # DW_AT_type
+ .long .LLST0 # DW_AT_location
+ .uleb128 0x9 # (DIE (0x106) DW_TAG_GNU_call_site)
+ .quad .LVL3 # DW_AT_low_pc
+ .long 0xab # DW_AT_abstract_origin
+ .byte 0 # end of children of DIE 0xda
+ .byte 0 # end of children of DIE 0xb
+ .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 0x3 # (DW_AT_name)
+ .uleb128 0xe # (DW_FORM_strp)
+ .uleb128 0x1b # (DW_AT_comp_dir)
+ .uleb128 0xe # (DW_FORM_strp)
+ .uleb128 0x55 # (DW_AT_ranges)
+ .uleb128 0x17 # (DW_FORM_sec_offset)
+ .uleb128 0x11 # (DW_AT_low_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 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 0x27 # (DW_AT_prototyped)
+ .uleb128 0x19 # (DW_FORM_flag_present)
+ .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 0x7 # (DW_FORM_data8)
+ .uleb128 0x40 # (DW_AT_frame_base)
+ .uleb128 0x18 # (DW_FORM_exprloc)
+ .uleb128 0x2117 # (DW_AT_GNU_all_call_sites)
+ .uleb128 0x19 # (DW_FORM_flag_present)
+ .byte 0
+ .byte 0
+ .uleb128 0x3 # (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 0x8 # (DW_FORM_string)
+ .byte 0
+ .byte 0
+ .uleb128 0x4 # (abbrev code)
+ .uleb128 0x2e # (TAG: DW_TAG_subprogram)
+ .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 0x27 # (DW_AT_prototyped)
+ .uleb128 0x19 # (DW_FORM_flag_present)
+ .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 0x7 # (DW_FORM_data8)
+ .uleb128 0x40 # (DW_AT_frame_base)
+ .uleb128 0x18 # (DW_FORM_exprloc)
+ .uleb128 0x2117 # (DW_AT_GNU_all_call_sites)
+ .uleb128 0x19 # (DW_FORM_flag_present)
+ .uleb128 0x1 # (DW_AT_sibling)
+ .uleb128 0x13 # (DW_FORM_ref4)
+ .byte 0
+ .byte 0
+ .uleb128 0x5 # (abbrev code)
+ .uleb128 0x4109 # (TAG: DW_TAG_GNU_call_site)
+ .byte 0 # DW_children_no
+ .uleb128 0x11 # (DW_AT_low_pc)
+ .uleb128 0x1 # (DW_FORM_addr)
+ .uleb128 0x2115 # (DW_AT_GNU_tail_call)
+ .uleb128 0x19 # (DW_FORM_flag_present)
+ .uleb128 0x31 # (DW_AT_abstract_origin)
+ .uleb128 0x13 # (DW_FORM_ref4)
+ .byte 0
+ .byte 0
+ .uleb128 0x6 # (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 0x27 # (DW_AT_prototyped)
+ .uleb128 0x19 # (DW_FORM_flag_present)
+ .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 0x7 # (DW_FORM_data8)
+ .uleb128 0x40 # (DW_AT_frame_base)
+ .uleb128 0x18 # (DW_FORM_exprloc)
+ .uleb128 0x2117 # (DW_AT_GNU_all_call_sites)
+ .uleb128 0x19 # (DW_FORM_flag_present)
+ .uleb128 0x1 # (DW_AT_sibling)
+ .uleb128 0x13 # (DW_FORM_ref4)
+ .byte 0
+ .byte 0
+ .uleb128 0x7 # (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 0x27 # (DW_AT_prototyped)
+ .uleb128 0x19 # (DW_FORM_flag_present)
+ .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 0x7 # (DW_FORM_data8)
+ .uleb128 0x40 # (DW_AT_frame_base)
+ .uleb128 0x18 # (DW_FORM_exprloc)
+ .uleb128 0x2117 # (DW_AT_GNU_all_call_sites)
+ .uleb128 0x19 # (DW_FORM_flag_present)
+ .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 0x17 # (DW_FORM_sec_offset)
+ .byte 0
+ .byte 0
+ .uleb128 0x9 # (abbrev code)
+ .uleb128 0x4109 # (TAG: DW_TAG_GNU_call_site)
+ .byte 0 # DW_children_no
+ .uleb128 0x11 # (DW_AT_low_pc)
+ .uleb128 0x1 # (DW_FORM_addr)
+ .uleb128 0x31 # (DW_AT_abstract_origin)
+ .uleb128 0x13 # (DW_FORM_ref4)
+ .byte 0
+ .byte 0
+ .byte 0
+ .section .debug_loc,"",@progbits
+.Ldebug_loc0:
+.LLST0:
+ .quad .LVL3 # Location list begin address (*.LLST0)
+ .quad .LVL4 # Location list end address (*.LLST0)
+ .value 0x3 # Location expression size
+ .byte 0x70 # DW_OP_breg0
+ .sleb128 1
+ .byte 0x9f # DW_OP_stack_value
+ .quad .LVL4 # Location list begin address (*.LLST0)
+ .quad .LFE4 # Location list end address (*.LLST0)
+ .value 0x1 # Location expression size
+ .byte 0x50 # DW_OP_reg0
+ .quad 0 # Location list terminator begin (*.LLST0)
+ .quad 0 # Location list terminator end (*.LLST0)
+ .section .debug_aranges,"",@progbits
+ .long 0x3c # 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 .LFB4 # Address
+ .quad .LFE4-.LFB4 # Length
+ .quad 0
+ .quad 0
+ .section .debug_ranges,"",@progbits
+.Ldebug_ranges0:
+ .quad .Ltext0 # Offset 0
+ .quad .Letext0
+ .quad .LFB4 # Offset 0x10
+ .quad .LFE4
+ .quad 0
+ .quad 0
+ .section .debug_line,"",@progbits
+.Ldebug_line0:
+ .section .debug_str,"MS",@progbits,1
+.LASF4:
+ .string "bar_1"
+.LASF2:
+ .string "tailcall-only.c"
+.LASF1:
+ .string "GNU C 4.8.3 20140911 (Red Hat 4.8.3-9) -mtune=generic -march=x86-64 -g -O2"
+.LASF6:
+ .string "answer"
+.LASF5:
+ .string "main"
+.LASF3:
+ .string ""
+.LASF0:
+ .string "foo_1"
+ .ident "GCC: (GNU) 4.8.3 20140911 (Red Hat 4.8.3-9)"
+ .section .note.GNU-stack,"",@progbits
--
1.8.3.1