Re: PING: [PATCH v4] fixed inherit_abstract_dies infinite recursive call

[Joel Brobecker <brobecker@adacore.com>]

[-- Attachment #1: Type: text/plain, Size: 408 bytes --]

> How hard is it to write a testcase that triggers the problem?

I wrote one and I thought I posted it here. But I had forgotten
to attach the patch! (git reflog just saved my life).

Here it is again.

gdb/testsuite/ChangeLog:

        * gdb.dwarf2/dw2-icycle.S, gdb.dwarf2/dw2-icycle.c,
        gdb.dwarf2/dw2-icycle.exp: New files.

This testcase fails without the patch being proposed.

Thanks,
-- 
Joel

[-- Attachment #2: 0001-New-asm-based-testcase-testing-DWARF-inlining-cycles.patch --]
[-- Type: text/x-diff, Size: 13159 bytes --]

From 9aa3343b7db4fceca64f587c763d4010146c7980 Mon Sep 17 00:00:00 2001
From: Joel Brobecker <brobecker@adacore.com>
Date: Tue, 28 Jan 2014 15:52:55 +0400
Subject: [PATCH] New asm-based testcase testing DWARF inlining cycles.

This testcase uses a dramatically reduced version of an assembly file
that was generated by GCC 4.9 when compiling at -O3, where nested
functions and inlining cause some cycles.  If the DWARF data is not
processed carefully, the debugger can go into infinite recursion,
eventually leading to a crash when the stack gets exhausted.

gdb/testsuite/ChangeLog:

        * gdb.dwarf2/dw2-icycle.S, gdb.dwarf2/dw2-icycle.c,
        gdb.dwarf2/dw2-icycle.exp: New files.
---
 gdb/testsuite/gdb.dwarf2/dw2-icycle.S   | 258 ++++++++++++++++++++++++++++++++
 gdb/testsuite/gdb.dwarf2/dw2-icycle.c   |  24 +++
 gdb/testsuite/gdb.dwarf2/dw2-icycle.exp |  43 ++++++
 3 files changed, 325 insertions(+)
 create mode 100644 gdb/testsuite/gdb.dwarf2/dw2-icycle.S
 create mode 100644 gdb/testsuite/gdb.dwarf2/dw2-icycle.c
 create mode 100644 gdb/testsuite/gdb.dwarf2/dw2-icycle.exp

diff --git a/gdb/testsuite/gdb.dwarf2/dw2-icycle.S b/gdb/testsuite/gdb.dwarf2/dw2-icycle.S
new file mode 100644
index 0000000..6bc533a
--- /dev/null
+++ b/gdb/testsuite/gdb.dwarf2/dw2-icycle.S
@@ -0,0 +1,258 @@
+/* This testcase is part of GDB, the GNU debugger.
+
+   Copyright 2014 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/>.  */
+
+	.text
+
+.Ltext0:
+	.type	p__top__middle__inside.3062, @function
+p__top__middle__inside.3062:
+.LFB4:
+	.file 1 "p.adb"
+        .4byte 0
+.LBE6:
+
+	.globl	p__top
+	.type	p__top, @function
+p__top:
+.LFB2:
+        .4byte 0
+.LFE2:
+.Letext0:
+
+	.section	.debug_info,"",@progbits
+.Ldebug_info0:
+	.4byte	.Ledebug_info0 - .Lsdebug_info0  /* Length of CU Info */
+.Lsdebug_info0:
+	.2byte	0x4	/* DWARF version number */
+	.4byte	.Ldebug_abbrev0	/* Offset Into Abbrev. Section */
+	.byte	0x4	/* Pointer Size (in bytes) */
+	.uleb128 0x1	/* (DIE (0xb) DW_TAG_compile_unit) */
+	.ascii	"GNU Ada 4.9.0 20140126\0" /* DW_AT_producer */
+	.byte	0xd	/* DW_AT_language */
+	.ascii	"p.adb\0" /* DW_AT_name */
+	.ascii	"/tmp\0"  /* DW_AT_comp_dir */
+	.4byte	.Ltext0	/* DW_AT_low_pc */
+	.4byte	.Letext0-.Ltext0	/* DW_AT_high_pc */
+.S0x142:
+	.uleb128 0x8	/* (DIE (0x142) DW_TAG_base_type) */
+	.byte	0x4	/* DW_AT_byte_size */
+	.byte	0x5	/* DW_AT_encoding */
+	.ascii	"integer\0" /* DW_AT_name */
+
+	.uleb128 0x13	/* (DIE (0x1b4) DW_TAG_subprogram) */
+			/* DW_AT_external */
+	.ascii	"p__top\0" /* DW_AT_name */
+	.byte	0x1	/* DW_AT_decl_file (p.adb) */
+	.byte	0x3	/* DW_AT_decl_line */
+	.4byte	.LFB2	/* DW_AT_low_pc */
+	.4byte	.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 */
+	.4byte	.S0x4fc - .Ldebug_info0	/* DW_AT_sibling */
+.S0x1e0:
+	.uleb128 0x15	/* (DIE (0x1e0) DW_TAG_subprogram) */
+	.ascii	"p__top__middle\0" /* DW_AT_name */
+	.byte	0x1	/* DW_AT_decl_file (p.adb) */
+	.byte	0x4	/* DW_AT_decl_line */
+	.byte	0x1	/* DW_AT_inline */
+	.4byte	.S0x374 - .Ldebug_info0	/* DW_AT_sibling */
+.S0x202:
+	.uleb128 0x15	/* (DIE (0x202) DW_TAG_subprogram) */
+	.ascii	"p__top__middle__inside\0" /* DW_AT_name */
+	.byte	0x1	/* DW_AT_decl_file (p.adb) */
+	.byte	0x5	/* DW_AT_decl_line */
+	.byte	0x1	/* DW_AT_inline */
+	.4byte	.S0x225	- .Ldebug_info0 /* DW_AT_sibling */
+	.byte	0	/* end of children of DIE 0x202 */
+.S0x225:
+	.uleb128 0x18	/* (DIE (0x225) DW_TAG_subprogram) */
+	.4byte	.S0x202 - .Ldebug_info0	/* DW_AT_abstract_origin */
+	.4byte	.LFB4	/* DW_AT_low_pc */
+	.4byte	.LBE6-.LFB4	/* DW_AT_high_pc */
+	.uleb128 0x1	/* DW_AT_frame_base */
+	.byte	0x9c	/* DW_OP_call_frame_cfa */
+	.uleb128 0x1	/* DW_AT_static_link */
+	.byte	0x56	/* DW_OP_reg6 */
+			/* DW_AT_GNU_all_call_sites */
+	.uleb128 0x1a	/* (DIE (0x247) DW_TAG_inlined_subroutine) */
+	.4byte	.S0x1e0 - .Ldebug_info0	/* DW_AT_abstract_origin */
+	.4byte	.LFB4	/* DW_AT_low_pc */
+	.4byte	.LBE6-.LFB4	/* DW_AT_high_pc */
+	.byte	0x1	/* DW_AT_call_file (p.adb) */
+	.byte	0x14	/* DW_AT_call_line */
+	.4byte	.S0x374	- .Ldebug_info0 /* DW_AT_sibling */
+	.byte	0	/* end of children of DIE 0x247 */
+	.byte	0	/* end of children of DIE 0x225 */
+	.byte	0	/* end of children of DIE 0x1e0 */
+.S0x374:
+	.uleb128 0x23	/* (DIE (0x382) DW_TAG_inlined_subroutine) */
+	.4byte	.S0x1e0 - .Ldebug_info0 /* DW_AT_abstract_origin */
+	.4byte	.LFB4	/* DW_AT_low_pc */
+	.4byte	.LBE6-.LFB4	/* DW_AT_high_pc */
+	.byte	0x1	/* DW_AT_call_file (p.adb) */
+	.byte	0x1d	/* DW_AT_call_line */
+	.byte	0	/* end of children of DIE 0x382 */
+	.byte	0	/* end of children of DIE 0x1b4 */
+.S0x4fc:
+	.uleb128 0x28	/* (DIE (0x52e) DW_TAG_subprogram) */
+			/* DW_AT_external */
+	.ascii	"__gnat_rcheck_PE_Explicit_Raise\0" /* DW_AT_name */
+			/* DW_AT_artificial */
+			/* DW_AT_declaration */
+	.byte	0	/* end of children of DIE 0x52e */
+	.byte	0	/* end of children of DIE 0xb */
+.Ledebug_info0:
+
+	.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 0x8	/* (DW_FORM_string) */
+	.uleb128 0x13	/* (DW_AT_language) */
+	.uleb128 0xb	/* (DW_FORM_data1) */
+	.uleb128 0x3	/* (DW_AT_name) */
+	.uleb128 0x8	/* (DW_FORM_string) */
+	.uleb128 0x1b	/* (DW_AT_comp_dir) */
+	.uleb128 0x8	/* (DW_FORM_string) */
+	.uleb128 0x11	/* (DW_AT_low_pc) */
+	.uleb128 0x1	/* (DW_FORM_addr) */
+	.uleb128 0x12	/* (DW_AT_high_pc) */
+	.uleb128 0x6	/* (DW_FORM_data4) */
+	.byte	0
+	.byte	0
+	.uleb128 0x8	/* (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 0x13	/* (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 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 0x15	/* (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 0x20	/* (DW_AT_inline) */
+	.uleb128 0xb	/* (DW_FORM_data1) */
+	.uleb128 0x1	/* (DW_AT_sibling) */
+	.uleb128 0x13	/* (DW_FORM_ref4) */
+	.byte	0
+	.byte	0
+	.uleb128 0x18	/* (abbrev code) */
+	.uleb128 0x2e	/* (TAG: DW_TAG_subprogram) */
+	.byte	0x1	/* DW_children_yes */
+	.uleb128 0x31	/* (DW_AT_abstract_origin) */
+	.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 0x48	/* (DW_AT_static_link) */
+	.uleb128 0x18	/* (DW_FORM_exprloc) */
+	.uleb128 0x2117	/* (DW_AT_GNU_all_call_sites) */
+	.uleb128 0x19	/* (DW_FORM_flag_present) */
+	.byte	0
+	.byte	0
+	.uleb128 0x1a	/* (abbrev code) */
+	.uleb128 0x1d	/* (TAG: DW_TAG_inlined_subroutine) */
+	.byte	0x1	/* DW_children_yes */
+	.uleb128 0x31	/* (DW_AT_abstract_origin) */
+	.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 0x58	/* (DW_AT_call_file) */
+	.uleb128 0xb	/* (DW_FORM_data1) */
+	.uleb128 0x59	/* (DW_AT_call_line) */
+	.uleb128 0xb	/* (DW_FORM_data1) */
+	.uleb128 0x1	/* (DW_AT_sibling) */
+	.uleb128 0x13	/* (DW_FORM_ref4) */
+	.byte	0
+	.byte	0
+	.uleb128 0x23	/* (abbrev code) */
+	.uleb128 0x1d	/* (TAG: DW_TAG_inlined_subroutine) */
+	.byte	0x1	/* DW_children_yes */
+	.uleb128 0x31	/* (DW_AT_abstract_origin) */
+	.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 0x58	/* (DW_AT_call_file) */
+	.uleb128 0xb	/* (DW_FORM_data1) */
+	.uleb128 0x59	/* (DW_AT_call_line) */
+	.uleb128 0xb	/* (DW_FORM_data1) */
+	.byte	0
+	.byte	0
+	.uleb128 0x28	/* (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 0x34	/* (DW_AT_artificial) */
+	.uleb128 0x19	/* (DW_FORM_flag_present) */
+	.uleb128 0x3c	/* (DW_AT_declaration) */
+	.uleb128 0x19	/* (DW_FORM_flag_present) */
+	.byte	0
+	.byte	0
+	.byte	0
+	.byte	0
+	.byte	0
+
+        .section .debug_line
+.Lline1_begin:
+        .byte   0
+
diff --git a/gdb/testsuite/gdb.dwarf2/dw2-icycle.c b/gdb/testsuite/gdb.dwarf2/dw2-icycle.c
new file mode 100644
index 0000000..3ddd194
--- /dev/null
+++ b/gdb/testsuite/gdb.dwarf2/dw2-icycle.c
@@ -0,0 +1,24 @@
+/* This testcase is part of GDB, the GNU debugger.
+
+   Copyright 2004-2014 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/>.  */
+
+/* Dummy main function.  */
+
+int
+main()
+{
+  return 0;
+}
diff --git a/gdb/testsuite/gdb.dwarf2/dw2-icycle.exp b/gdb/testsuite/gdb.dwarf2/dw2-icycle.exp
new file mode 100644
index 0000000..fcb57b6
--- /dev/null
+++ b/gdb/testsuite/gdb.dwarf2/dw2-icycle.exp
@@ -0,0 +1,43 @@
+# Copyright 2014 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
+}
+
+standard_testfile .S .c
+
+if { [prepare_for_testing ${testfile}.exp ${testfile} \
+	  [list $srcfile $srcfile2] {nodebug}] } {
+    return -1
+}
+
+# We are trying to verify that the partial symtab to symtab expansion
+# for the debugging info hand-coded in our assembly file does not cause
+# the debugger to crash (infinite recursion).  To facilitate the test,
+# start the debugger with -readnow.  This force expansion as soon as
+# the objfile is loaded.
+
+set saved_gdbflags $GDBFLAGS
+set GDBFLAGS "$GDBFLAGS -readnow"
+clean_restart ${testfile}
+set GDBFLAGS $saved_gdbflags
+
+# And just to be sure that the debugger did not crash after having
+# expanded our symbols, do a life-check.
+
+gdb_test "echo life check\\n" "life check"
-- 
1.8.3.2