This is the mail archive of the
gdb-patches@sourceware.org
mailing list for the GDB project.
Re: [patch] Fix `return' of long/long-long results with no debuginfo
- From: Jan Kratochvil <jan dot kratochvil at redhat dot com>
- To: Tom Tromey <tromey at redhat dot com>
- Cc: Mark Kettenis <mark dot kettenis at xs4all dot nl>, drow at false dot org, gdb-patches at sourceware dot org
- Date: Mon, 9 Mar 2009 02:55:10 +0100
- Subject: Re: [patch] Fix `return' of long/long-long results with no debuginfo
- References: <20090211205045.GB9762@caradoc.them.org> <200902112122.n1BLMf8q000100@brahms.sibelius.xs4all.nl> <20090211214646.GA22247@host0.dyn.jankratochvil.net> <200902112157.n1BLvplk011339@brahms.sibelius.xs4all.nl> <20090211220824.GA26040@host0.dyn.jankratochvil.net> <200902112237.n1BMbbOb006035@brahms.sibelius.xs4all.nl> <20090211225012.GA28683@host0.dyn.jankratochvil.net> <m3ocwimq9g.fsf@fleche.redhat.com> <200903042129.n24LTUKa000770@brahms.sibelius.xs4all.nl> <m3ljrkg703.fsf@fleche.redhat.com>
On Thu, 05 Mar 2009 01:15:08 +0100, Tom Tromey wrote:
> >>>>> "Mark" == Mark Kettenis <mark.kettenis@xs4all.nl> writes:
>
> Mark> Do we have a way to figure out if such a cast is present in the
> Mark> expression passed as an argument to the return command?
>
> Yeah, it is not too hard. It just means having return_command call
> parse_expression directly, then look at the resulting expression.
Attached, check-in approval requested.
Regards,
Jan
gdb/
2009-03-09 Jan Kratochvil <jan.kratochvil@redhat.com>
* stack.c (return_command <retval_exp>): New variables retval_expr
and old_chain. Inline parse_and_eval to initialize retval_expr. Check
RETVAL_EXPR for UNOP_CAST and set RETURN_TYPE to the RETURN_VALUE type
if RETURN_TYPE is NULL.
gdb/testsuite/
2009-03-09 Jan Kratochvil <jan.kratochvil@redhat.com>
* gdb.base/return-nodebug.exp, gdb.base/return-nodebug.S: New.
--- gdb/stack.c 6 Mar 2009 18:51:05 -0000 1.186
+++ gdb/stack.c 9 Mar 2009 01:52:55 -0000
@@ -1796,18 +1796,26 @@ return_command (char *retval_exp, int fr
message. */
if (retval_exp)
{
+ struct expression *retval_expr = parse_expression (retval_exp);
+ struct cleanup *old_chain = make_cleanup (xfree, retval_expr);
struct type *return_type = NULL;
/* Compute the return value. Should the computation fail, this
call throws an error. */
- return_value = parse_and_eval (retval_exp);
+ return_value = evaluate_expression (retval_expr);
/* Cast return value to the return type of the function. Should
the cast fail, this call throws an error. */
if (thisfun != NULL)
return_type = TYPE_TARGET_TYPE (SYMBOL_TYPE (thisfun));
if (return_type == NULL)
- return_type = builtin_type (get_frame_arch (thisframe))->builtin_int;
+ {
+ if (retval_expr->elts[0].opcode != UNOP_CAST)
+ error (_("Selected stack frame (with no associated function) "
+ "requires an explicit cast of the value to return"));
+ return_type = value_type (return_value);
+ }
+ do_cleanups (old_chain);
CHECK_TYPEDEF (return_type);
return_value = value_cast (return_type, return_value);
--- /dev/null 1 Jan 1970 00:00:00 -0000
+++ gdb/testsuite/gdb.base/return-nodebug.c 9 Mar 2009 01:52:55 -0000
@@ -0,0 +1,49 @@
+/* This testcase is part of GDB, the GNU debugger.
+
+ Copyright 2009 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/>. */
+
+#include <stdio.h>
+
+static TYPE
+init (void)
+{
+ return 0;
+}
+
+static TYPE
+func (void)
+{
+ return 31;
+}
+
+static void
+marker (void)
+{
+}
+
+int
+main (void)
+{
+ /* Preinitialize registers to 0 to avoid false PASS by leftover garbage. */
+ init ();
+
+ printf ("result=" FORMAT "\n", CAST func ());
+
+ /* Cannot `next' with no debug info. */
+ marker ();
+
+ return 0;
+}
--- /dev/null 1 Jan 1970 00:00:00 -0000
+++ gdb/testsuite/gdb.base/return-nodebug.exp 9 Mar 2009 01:52:55 -0000
@@ -0,0 +1,60 @@
+# Copyright (C) 2009 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/>.
+
+proc do_test {type} {
+ set typenospace [string map {{ } -} $type]
+
+ global pf_prefix
+ set old_prefix $pf_prefix
+ lappend pf_prefix "$typenospace:"
+
+ if {[runto "func"]} {
+ # Test return from a function with no debug info (symbol; still it may
+ # have a minimal-symbol) if it does not crash.
+
+ gdb_test "return -1" \
+ "Selected stack frame \\(with no associated function\\) requires an explicit cast of the value to return" \
+ "return from function with no debug info without a cast"
+
+ # Cast of the result to the proper width must be done explicitely.
+ gdb_test "return ($type) -1" "#0 .* main \\(.*" \
+ "return from function with no debug info with a cast" \
+ "Make selected stack frame return now\\? \\(y or n\\) " "y"
+
+ # And if it returned the full width of the result.
+ gdb_test "adv marker" "\r\nresult=-1\r\n.* in marker \\(.*" \
+ "full width of the returned result"
+ }
+
+ set pf_prefix $old_prefix
+}
+
+foreach case {{{signed char} %d (int)} \
+ {{short} %d (int)} \
+ {{int} %d} \
+ {{long} %ld} \
+ {{long long} %lld}} {
+ set type [lindex $case 0]
+ set format [lindex $case 1]
+ set cast [lindex $case 2]
+
+ set typeesc [string map {{ } {\ }} $type]
+ set typenospace [string map {{ } -} $type]
+
+ if {[prepare_for_testing return-nodebug.exp "return-nodebug-$typenospace" "return-nodebug.c" \
+ [list "additional_flags=-DFORMAT=\"$format\" -DTYPE=$typeesc -DCAST=$cast"]] == 0} {
+ do_test $type
+ }
+}