On Mon, 2011-04-11 at 13:02 +0200, Petr Machata wrote:
The original theory must have been that form_class won't be
unless you know the form/attr combo makes sense. But it will be easier
your way, max_dw_class is checked for anyway. So go ahead and merge
If you have an example binary, please add it to a test suite.
I added an example to the testsuite. It asserts/crashes without the
patch, and succeeds silently with it.
Author: Mark Wielaard <mjw(a)redhat.com>
Date: Mon Apr 11 13:55:58 2011 +0200
dwarflint: Don't assert in check_debug_info can trigger an assert.
Instead of asserting a form must exist, let form_class () return
max_dw_class, like ambiguous_class () does. max_dw_class is already
used as sentinel in read_die_chain () in case the attribute is unknown.
This lets things work out for the low level check_debug_info check and
then makes the higher-level checks complain about the unexpected form
instead. Added an example binary and test dwarflint/tests/run-upper.sh.
diff --git a/dwarflint/Makefile.am b/dwarflint/Makefile.am
index 56e2611..f8d03c3 100644
@@ -117,7 +117,8 @@ EXTRA_TESTS = tests/run-debug_abbrev-duplicate-attribute.sh \
+ tests/run-DW_AT-later-version.sh \
TESTS = $(EXTRA_TESTS) \
@@ -150,7 +151,8 @@ EXTRA_DIST = $(EXTRA_TESTS) \
+ tests/DW_AT-later-version.bz2 \
installed_TESTS_ENVIRONMENT = libdir=$(DESTDIR)$(libdir) \
diff --git a/dwarflint/check_debug_info.cc b/dwarflint/check_debug_info.cc
index 46d4ec5..c880fd9 100644
@@ -796,8 +796,11 @@ namespace
valuep = &high_pc;
if (cls == cl_constant)
high_pc_relative = true;
- assert (cls == cl_address);
+ else if (cls != cl_address)
+ wr_error (&where, ": DW_AT_high_pc in unknown form.\n");
+ retval = -2;
diff --git a/dwarflint/dwarf_version.cc b/dwarflint/dwarf_version.cc
index 8a34ef0..28404a2 100644
@@ -87,7 +87,6 @@ dwarf_version::form_class (form const *form, attribute const *attribute)
assert (attribute != NULL);
dw_class_set result = form->classes ();
result &= attribute->classes ();
- assert (result.any ());
if (result.count () > 1)
dw_class ret = this->ambiguous_class (form, attribute, result);
@@ -95,8 +94,10 @@ dwarf_version::form_class (form const *form, attribute const
+ else if (result.count () == 1)
return static_cast<dw_class> (ffsl (result.to_ulong ()) - 1);
+ return max_dw_class;
diff --git a/dwarflint/tests/run-upper.sh b/dwarflint/tests/run-upper.sh
new file mode 100755
@@ -0,0 +1,56 @@
+# Copyright (C) 2011 Red Hat, Inc.
+# This file is part of Red Hat elfutils.
+# Red Hat elfutils 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; version 2 of the License.
+# Red Hat elfutils 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 Red Hat elfutils; if not, write to the Free Software Foundation,
+# Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301 USA.
+# Red Hat elfutils is an included package of the Open Invention Network.
+# An included package of the Open Invention Network is a package for which
+# Open Invention Network licensees cross-license their patents. No patent
+# license is granted, either expressly or impliedly, by designation as an
+# included package. Should you wish to participate in the Open Invention
+# Network licensing program, please visit www.openinventionnetwork.com
+# Following program compiled with "default" gcc settings,
+# which is dwarf-2 + gnu extensions. Which will result in:
+# [ a2] subrange_type
+# type (ref4) [ ac]
+# upper_bound (block1)
+# [ 0] fbreg -24
+# [ 2] deref
+# According to dwarf-2 DW_AT_upperbound cannot be encoded with block form.
+# It can however with later versions of dwarf, which gcc will output as
+# gnu extension (unless -gstrict-dwarf is given).
+# int max_range = 42;
+# int main (int argc, char **argv)
+# char chars[max_range];
+# chars[max_range -1] = 7;
+# return 0;
+# This would crash the low-level check_debug_info in the past.
+testrun_compare ./dwarflint --quiet --check=@low upper <<EOF
diff --git a/dwarflint/tests/upper.bz2 b/dwarflint/tests/upper.bz2
new file mode 100755
Binary files /dev/null and b/dwarflint/tests/upper.bz2 differ