diff mbox

testcase: tailcall assertion [Re: [PATCH] Fix wrong assertions]

Message ID 20150519204645.GA32163@host1.jankratochvil.net
State New
Headers show

Commit Message

Jan Kratochvil May 19, 2015, 8:46 p.m. UTC
On Sat, 09 May 2015 20:56:55 +0200, Andreas Schwab wrote:
> Both callers and callees are lengths, and the sum of them can validly
> equal the total length.

This can happen for functions tail-calling themselves.

This is what GCC generated for cc1.  I was unable to create a .c file
reproducing it (GCC does not generate tail-call call site DWARF for the
self-tail-call) but a hand crafted DWARF can crash GDB like cc1 does.


Thanks,
Jan
gdb/testsuite/ChangeLog
2015-05-19  Jan Kratochvil  <jan.kratochvil@redhat.com>

	* gdb.arch/amd64-tailcall-self.S: New file.
	* gdb.arch/amd64-tailcall-self.c: New file.
	* gdb.arch/amd64-tailcall-self.exp: New file.
diff mbox

Patch

diff --git a/gdb/testsuite/gdb.arch/amd64-tailcall-self.S b/gdb/testsuite/gdb.arch/amd64-tailcall-self.S
new file mode 100644
index 0000000..b1ca7c8
--- /dev/null
+++ b/gdb/testsuite/gdb.arch/amd64-tailcall-self.S
@@ -0,0 +1,614 @@ 
+/* This testcase is part of GDB, the GNU debugger.
+
+   Copyright 2015 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 source file was generated by:
+   gcc -o gdb.arch/amd64-tailcall-self.S -S gdb.arch/amd64-tailcall-self.c -Wall -g -dA -Os
+   */
+
+	.file	"amd64-tailcall-self.c"
+	.text
+.Ltext0:
+	.section	.text.unlikely,"ax",@progbits
+.LCOLDB0:
+	.text
+.LHOTB0:
+	.section	.text.unlikely
+.Ltext_cold0:
+	.text
+	.type	b, @function
+b:
+.LFB0:
+	.file 1 "amd64-tailcall-self.c"
+	# amd64-tailcall-self.c:1
+	.loc 1 1 0
+	.cfi_startproc
+# BLOCK 2 freq:10000 seq:0
+# PRED: ENTRY [100.0%]  (FALLTHRU)
+	# amd64-tailcall-self.c:2
+	.loc 1 2 0
+# SUCC: EXIT [100.0%] 
+	ret
+	.cfi_endproc
+.LFE0:
+	.size	b, .-b
+	.section	.text.unlikely
+.LCOLDE0:
+	.text
+.LHOTE0:
+	.section	.text.unlikely
+.LCOLDB1:
+	.text
+.LHOTB1:
+	.globl	c
+	.type	c, @function
+c:
+.LFB1:
+	# amd64-tailcall-self.c:7
+	.loc 1 7 0
+	.cfi_startproc
+.LVL0:
+# BLOCK 2 freq:10000 seq:0
+# PRED: ENTRY [100.0%]  (FALLTHRU)
+	# amd64-tailcall-self.c:8
+	.loc 1 8 0
+	leal	1(%rdi), %eax
+# SUCC: EXIT [100.0%] 
+	# amd64-tailcall-self.c:9
+	.loc 1 9 0
+	ret
+	.cfi_endproc
+.LFE1:
+	.size	c, .-c
+	.section	.text.unlikely
+.LCOLDE1:
+	.text
+.LHOTE1:
+	.section	.text.unlikely
+.LCOLDB2:
+	.text
+.LHOTB2:
+	.globl	a
+	.type	a, @function
+a:
+.LFB2:
+	# amd64-tailcall-self.c:11
+	.loc 1 11 0
+	.cfi_startproc
+.LVL1:
+# BLOCK 2 freq:10000 seq:0
+# PRED: ENTRY [100.0%]  (FALLTHRU) 3 [100.0%]  (DFS_BACK,CAN_FALLTHRU)
+.L5:
+	# amd64-tailcall-self.c:12
+	.loc 1 12 0
+#APP
+# 12 "amd64-tailcall-self.c" 1
+	nop;nop;nop
+# 0 "" 2
+	# amd64-tailcall-self.c:13
+	.loc 1 13 0
+#NO_APP
+	movl	i(%rip), %edi
+	leal	-1(%rdi), %eax
+	cmpl	$9, %eax
+# SUCC: 3 [91.0%]  (FALLTHRU,CAN_FALLTHRU) 4 [9.0%]  (CAN_FALLTHRU,LOOP_EXIT)
+	ja	.L4
+# BLOCK 3 freq:9100 seq:1
+# PRED: 2 [91.0%]  (FALLTHRU,CAN_FALLTHRU)
+	# amd64-tailcall-self.c:14
+	.loc 1 14 0
+	orl	$1, %edi
+	movl	%edi, i(%rip)
+# SUCC: 2 [100.0%]  (DFS_BACK,CAN_FALLTHRU)
+	jmp	.L5
+.Lfirsttailcall:
+# BLOCK 4 freq:900 seq:2
+# PRED: 2 [9.0%]  (CAN_FALLTHRU,LOOP_EXIT)
+.L4:
+	# amd64-tailcall-self.c:16
+	.loc 1 16 0
+	cmpl	$0, %edi
+# SUCC: 5 [19.9%]  (FALLTHRU,CAN_FALLTHRU) 6 [80.1%]  (CAN_FALLTHRU)
+	jne	.L3
+# BLOCK 5 freq:179 seq:3
+# PRED: 4 [19.9%]  (FALLTHRU,CAN_FALLTHRU)
+# SUCC: EXIT [100.0%]  (ABNORMAL,SIBCALL)
+	# amd64-tailcall-self.c:17
+	.loc 1 17 0
+	jmp	b
+.LVL2:
+# BLOCK 6 freq:721 seq:4
+# PRED: 4 [80.1%]  (CAN_FALLTHRU)
+.L3:
+# SUCC: EXIT [100.0%] 
+	ret
+	.cfi_endproc
+.LFE2:
+	.size	a, .-a
+	.section	.text.unlikely
+.LCOLDE2:
+	.text
+.LHOTE2:
+	.section	.text.unlikely
+.LCOLDB3:
+	.section	.text.startup,"ax",@progbits
+.LHOTB3:
+	.globl	main
+	.type	main, @function
+main:
+.LFB3:
+	# amd64-tailcall-self.c:20
+	.loc 1 20 0
+	.cfi_startproc
+.LVL3:
+# BLOCK 2 freq:10000 seq:0
+# PRED: ENTRY [100.0%]  (FALLTHRU)
+	# amd64-tailcall-self.c:21
+	.loc 1 21 0
+	call	a
+.LVL4:
+	# amd64-tailcall-self.c:23
+	.loc 1 23 0
+	xorl	%eax, %eax
+# SUCC: EXIT [100.0%] 
+	ret
+	.cfi_endproc
+.LFE3:
+	.size	main, .-main
+	.section	.text.unlikely
+.LCOLDE3:
+	.section	.text.startup
+.LHOTE3:
+	.comm	i,4,4
+	.text
+.Letext0:
+	.section	.text.unlikely
+.Letext_cold0:
+	.section	.debug_info,"",@progbits
+.Ldebug_info0:
+	.long	2f-1f	# Length of Compilation Unit Info
+1:
+	.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	.LASF4	# DW_AT_producer: "GNU C 4.9.2 20150212 (Red Hat 4.9.2-6) -mtune=generic -march=x86-64 -g -Os"
+	.byte	0x1	# DW_AT_language
+	.long	.LASF5	# DW_AT_name: "amd64-tailcall-self.c"
+	.long	.LASF6	# DW_AT_comp_dir: "/home/jkratoch/t"
+	.long	.Ldebug_ranges0+0	# DW_AT_ranges
+	.quad	0	# DW_AT_low_pc
+	.long	.Ldebug_line0	# DW_AT_stmt_list
+die29:
+	.uleb128 0x2	# (DIE (0x29) DW_TAG_subprogram)
+	.ascii "b\0"	# DW_AT_name
+	.byte	0x1	# DW_AT_decl_file (amd64-tailcall-self.c)
+	.byte	0x1	# DW_AT_decl_line
+			# DW_AT_prototyped
+	.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 (0x40) DW_TAG_subprogram)
+			# DW_AT_external
+	.ascii "c\0"	# DW_AT_name
+	.byte	0x1	# DW_AT_decl_file (amd64-tailcall-self.c)
+	.byte	0x7	# DW_AT_decl_line
+			# DW_AT_prototyped
+	.long	die6b	# 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
+	.uleb128 0x4	# (DIE (0x5f) DW_TAG_formal_parameter)
+	.ascii "q\0"	# DW_AT_name
+	.byte	0x1	# DW_AT_decl_file (amd64-tailcall-self.c)
+	.byte	0x7	# DW_AT_decl_line
+	.long	die6b	# DW_AT_type
+	.uleb128 0x1	# DW_AT_location
+	.byte	0x55	# DW_OP_reg5
+	.byte	0	# end of children of DIE 0x40
+die6b:
+	.uleb128 0x5	# (DIE (0x6b) DW_TAG_base_type)
+	.byte	0x4	# DW_AT_byte_size
+	.byte	0x5	# DW_AT_encoding
+	.ascii "int\0"	# DW_AT_name
+die72:
+	.uleb128 0x6	# (DIE (0x72) DW_TAG_subprogram)
+			# DW_AT_external
+	.ascii "a\0"	# DW_AT_name
+	.byte	0x1	# DW_AT_decl_file (amd64-tailcall-self.c)
+	.byte	0xb	# DW_AT_decl_line
+			# DW_AT_prototyped
+	.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
+	.uleb128 0x4	# (DIE (0x8d) DW_TAG_formal_parameter)
+	.ascii "q\0"	# DW_AT_name
+	.byte	0x1	# DW_AT_decl_file (amd64-tailcall-self.c)
+	.byte	0xb	# DW_AT_decl_line
+	.long	die6b	# DW_AT_type
+	.uleb128 0x4	# DW_AT_location
+	.byte	0xf3	# DW_OP_GNU_entry_value
+	.uleb128 0x1
+	.byte	0x55	# DW_OP_reg5
+	.byte	0x9f	# DW_OP_stack_value
+	.uleb128 0x7	# (DIE () DW_TAG_GNU_call_site)
+	.quad	.Lfirsttailcall	# DW_AT_low_pc
+			# DW_AT_GNU_tail_call
+	.long	die72	# DW_AT_abstract_origin
+	.uleb128 0x7	# (DIE (0x9b) DW_TAG_GNU_call_site)
+	.quad	.LVL2	# DW_AT_low_pc
+			# DW_AT_GNU_tail_call
+	.long	die29	# DW_AT_abstract_origin
+	.byte	0	# end of children of DIE 0x72
+	.uleb128 0x8	# (DIE (0xa9) DW_TAG_subprogram)
+			# DW_AT_external
+	.long	.LASF0	# DW_AT_name: "main"
+	.byte	0x1	# DW_AT_decl_file (amd64-tailcall-self.c)
+	.byte	0x14	# DW_AT_decl_line
+			# DW_AT_prototyped
+	.long	die6b	# 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
+	.uleb128 0x9	# (DIE (0xca) DW_TAG_formal_parameter)
+	.long	.LASF1	# DW_AT_name: "argc"
+	.byte	0x1	# DW_AT_decl_file (amd64-tailcall-self.c)
+	.byte	0x14	# DW_AT_decl_line
+	.long	die6b	# DW_AT_type
+	.long	.LLST0	# DW_AT_location
+	.uleb128 0x9	# (DIE (0xd9) DW_TAG_formal_parameter)
+	.long	.LASF2	# DW_AT_name: "argv"
+	.byte	0x1	# DW_AT_decl_file (amd64-tailcall-self.c)
+	.byte	0x14	# DW_AT_decl_line
+	.long	diefe	# DW_AT_type
+	.long	.LLST1	# DW_AT_location
+	.uleb128 0xa	# (DIE (0xe8) DW_TAG_GNU_call_site)
+	.quad	.LVL4	# DW_AT_low_pc
+	.long	die72	# DW_AT_abstract_origin
+	.uleb128 0xb	# (DIE (0xf5) DW_TAG_GNU_call_site_parameter)
+	.uleb128 0x1	# DW_AT_location
+	.byte	0x55	# DW_OP_reg5
+	.uleb128 0x3	# DW_AT_GNU_call_site_value
+	.byte	0xf3	# DW_OP_GNU_entry_value
+	.uleb128 0x1
+	.byte	0x55	# DW_OP_reg5
+	.byte	0	# end of children of DIE 0xe8
+	.byte	0	# end of children of DIE 0xa9
+diefe:
+	.uleb128 0xc	# (DIE (0xfe) DW_TAG_pointer_type)
+	.byte	0x8	# DW_AT_byte_size
+	.long	die104	# DW_AT_type
+die104:
+	.uleb128 0xc	# (DIE (0x104) DW_TAG_pointer_type)
+	.byte	0x8	# DW_AT_byte_size
+	.long	die10a	# DW_AT_type
+die10a:
+	.uleb128 0xd	# (DIE (0x10a) DW_TAG_base_type)
+	.byte	0x1	# DW_AT_byte_size
+	.byte	0x6	# DW_AT_encoding
+	.long	.LASF3	# DW_AT_name: "char"
+	.uleb128 0xe	# (DIE (0x111) DW_TAG_variable)
+	.ascii "i\0"	# DW_AT_name
+	.byte	0x1	# DW_AT_decl_file (amd64-tailcall-self.c)
+	.byte	0x5	# DW_AT_decl_line
+	.long	die6b	# DW_AT_type
+			# DW_AT_external
+	.uleb128 0x9	# DW_AT_location
+	.byte	0x3	# DW_OP_addr
+	.quad	i
+	.byte	0	# end of children of DIE 0xb
+2:
+	.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 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 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 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 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 0x4	# (abbrev code)
+	.uleb128 0x5	# (TAG: DW_TAG_formal_parameter)
+	.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 0x5	# (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 0x6	# (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 0x27	# (DW_AT_prototyped)
+	.uleb128 0x19	# (DW_FORM_flag_present)
+	.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 0x7	# (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 0x8	# (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 0x9	# (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 0x17	# (DW_FORM_sec_offset)
+	.byte	0
+	.byte	0
+	.uleb128 0xa	# (abbrev code)
+	.uleb128 0x4109	# (TAG: DW_TAG_GNU_call_site)
+	.byte	0x1	# DW_children_yes
+	.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
+	.uleb128 0xb	# (abbrev code)
+	.uleb128 0x410a	# (TAG: DW_TAG_GNU_call_site_parameter)
+	.byte	0	# DW_children_no
+	.uleb128 0x2	# (DW_AT_location)
+	.uleb128 0x18	# (DW_FORM_exprloc)
+	.uleb128 0x2111	# (DW_AT_GNU_call_site_value)
+	.uleb128 0x18	# (DW_FORM_exprloc)
+	.byte	0
+	.byte	0
+	.uleb128 0xc	# (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 0xd	# (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 0xe	# (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
+	.byte	0
+	.section	.debug_loc,"",@progbits
+.Ldebug_loc0:
+.LLST0:
+	.quad	.LVL3	# Location list begin address (*.LLST0)
+	.quad	.LVL4-1	# Location list end address (*.LLST0)
+	.value	0x1	# Location expression size
+	.byte	0x55	# DW_OP_reg5
+	.quad	.LVL4-1	# Location list begin address (*.LLST0)
+	.quad	.LFE3	# Location list end address (*.LLST0)
+	.value	0x4	# Location expression size
+	.byte	0xf3	# DW_OP_GNU_entry_value
+	.uleb128 0x1
+	.byte	0x55	# DW_OP_reg5
+	.byte	0x9f	# DW_OP_stack_value
+	.quad	0	# Location list terminator begin (*.LLST0)
+	.quad	0	# Location list terminator end (*.LLST0)
+.LLST1:
+	.quad	.LVL3	# Location list begin address (*.LLST1)
+	.quad	.LVL4-1	# Location list end address (*.LLST1)
+	.value	0x1	# Location expression size
+	.byte	0x54	# DW_OP_reg4
+	.quad	.LVL4-1	# Location list begin address (*.LLST1)
+	.quad	.LFE3	# Location list end address (*.LLST1)
+	.value	0x4	# Location expression size
+	.byte	0xf3	# DW_OP_GNU_entry_value
+	.uleb128 0x1
+	.byte	0x54	# DW_OP_reg4
+	.byte	0x9f	# DW_OP_stack_value
+	.quad	0	# Location list terminator begin (*.LLST1)
+	.quad	0	# Location list terminator end (*.LLST1)
+	.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	.LFB3	# Address
+	.quad	.LFE3-.LFB3	# Length
+	.quad	0
+	.quad	0
+	.section	.debug_ranges,"",@progbits
+.Ldebug_ranges0:
+	.quad	.Ltext0	# Offset 0
+	.quad	.Letext0
+	.quad	.LFB3	# Offset 0x10
+	.quad	.LFE3
+	.quad	0
+	.quad	0
+	.section	.debug_line,"",@progbits
+.Ldebug_line0:
+	.section	.debug_str,"MS",@progbits,1
+.LASF1:
+	.string	"argc"
+.LASF0:
+	.string	"main"
+.LASF4:
+	.string	"GNU C 4.9.2 20150212 (Red Hat 4.9.2-6) -mtune=generic -march=x86-64 -g -Os"
+.LASF5:
+	.string	"amd64-tailcall-self.c"
+.LASF6:
+	.string	""
+.LASF3:
+	.string	"char"
+.LASF2:
+	.string	"argv"
+	.ident	"GCC: (GNU) 4.9.2 20150212 (Red Hat 4.9.2-6)"
diff --git a/gdb/testsuite/gdb.arch/amd64-tailcall-self.c b/gdb/testsuite/gdb.arch/amd64-tailcall-self.c
new file mode 100644
index 0000000..0b40dcb
--- /dev/null
+++ b/gdb/testsuite/gdb.arch/amd64-tailcall-self.c
@@ -0,0 +1,40 @@ 
+/* This testcase is part of GDB, the GNU debugger.
+
+   Copyright 2015 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/>.  */
+
+__attribute__((noinline,noclone)) static void b(void) {
+  asm volatile("");
+}
+
+int i;
+
+__attribute__((noinline,noclone)) int c(int q) {
+  return q+1;
+}
+
+__attribute__((noinline,noclone)) void a(int q) {
+  asm volatile("nop;nop;nop"::"g"(q):"memory");
+  if (i>=1&&i<=10) {
+    i|=1;
+    a(i);
+  } else if (i==0)
+    b();
+}
+
+int main(int argc,char **argv) {
+  a(argc);
+  return 0;
+}
diff --git a/gdb/testsuite/gdb.arch/amd64-tailcall-self.exp b/gdb/testsuite/gdb.arch/amd64-tailcall-self.exp
new file mode 100644
index 0000000..0803ff2
--- /dev/null
+++ b/gdb/testsuite/gdb.arch/amd64-tailcall-self.exp
@@ -0,0 +1,31 @@ 
+# Copyright (C) 2015 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/>.
+
+standard_testfile .S
+
+if { ![istarget x86_64-*-* ] || ![is_lp64_target] } {
+    verbose "Skipping ${testfile}."
+    return
+}
+
+if { [prepare_for_testing ${testfile}.exp ${testfile} ${srcfile} {}] } {
+    return -1
+}
+
+if ![runto b] {
+    return -1
+}
+
+gdb_test "bt" "#0 +b \\(\\) at \[^\r\n\]*\r\n#1 +0x\[0-9a-f\]+ in a \\(q=<optimized out>\\) at \[^\r\n\]*\r\n#2 +0x\[0-9a-f\]+ in main \\(\[^\r\n\]*\\) at .*"