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RFC: Print the type of a C value in one more case
- From: Daniel Jacobowitz <drow at false dot org>
- To: gdb-patches at sources dot redhat dot com
- Date: Sun, 6 Mar 2005 12:45:29 -0500
- Subject: RFC: Print the type of a C value in one more case
This is something that constantly bugs me when debugging GCC. GCC has
typedefs for "tree" and "rtx" which are both pointers to structs. When
you print either, you just get "$1 = 0xbf000100" without any indication of
the type of the variable; but normally GDB prints types for pointers.
This comes from a missing check_typedef in c_value_print.
There were a couple of ways to fix it; I chose to print the typedef rather
than what the typedef pointed to. The only difference in the testsuite is
in one objc test, which perfectly illustrates the desired change:
-$1 = 0x0
+$1 = (id) 0x0
Any comments?
--
Daniel Jacobowitz
CodeSourcery, LLC
2005-03-06 Daniel Jacobowitz <dan@codesourcery.com>
* c-valprint.c (c_value_print): Fix up some formatting. Use
check_typedef.
2005-03-06 Daniel Jacobowitz <dan@codesourcery.com>
* gdb.base/ptr-typedef.exp, gdb.base/ptr-typedef.c: New files.
Index: c-valprint.c
===================================================================
RCS file: /cvs/src/src/gdb/c-valprint.c,v
retrieving revision 1.35
diff -u -p -r1.35 c-valprint.c
--- c-valprint.c 28 Feb 2005 17:00:48 -0000 1.35
+++ c-valprint.c 6 Mar 2005 17:42:16 -0000
@@ -491,8 +491,7 @@ int
c_value_print (struct value *val, struct ui_file *stream, int format,
enum val_prettyprint pretty)
{
- struct type *type = value_type (val);
- struct type *real_type;
+ struct type *type, *real_type;
int full, top, using_enc;
/* If it is a pointer, indicate what it points to.
@@ -501,15 +500,18 @@ c_value_print (struct value *val, struct
C++: if it is a member pointer, we will take care
of that when we print it. */
- if (TYPE_CODE (type) == TYPE_CODE_PTR ||
- TYPE_CODE (type) == TYPE_CODE_REF)
+
+ type = check_typedef (value_type (val));
+
+ if (TYPE_CODE (type) == TYPE_CODE_PTR
+ || TYPE_CODE (type) == TYPE_CODE_REF)
{
/* Hack: remove (char *) for char strings. Their
type is indicated by the quoted string anyway. */
- if (TYPE_CODE (type) == TYPE_CODE_PTR &&
- TYPE_NAME (type) == NULL &&
- TYPE_NAME (TYPE_TARGET_TYPE (type)) != NULL &&
- strcmp (TYPE_NAME (TYPE_TARGET_TYPE (type)), "char") == 0)
+ if (TYPE_CODE (type) == TYPE_CODE_PTR
+ && TYPE_NAME (type) == NULL
+ && TYPE_NAME (TYPE_TARGET_TYPE (type)) != NULL
+ && strcmp (TYPE_NAME (TYPE_TARGET_TYPE (type)), "char") == 0)
{
/* Print nothing */
}
@@ -556,11 +558,12 @@ c_value_print (struct value *val, struct
{
/* normal case */
fprintf_filtered (stream, "(");
- type_print (type, "", stream, -1);
+ type_print (value_type (val), "", stream, -1);
fprintf_filtered (stream, ") ");
}
}
- if (objectprint && (TYPE_CODE (value_type (val)) == TYPE_CODE_CLASS))
+
+ if (objectprint && (TYPE_CODE (type) == TYPE_CODE_CLASS))
{
/* Attempt to determine real type of object */
real_type = value_rtti_type (val, &full, &top, &using_enc);
@@ -578,7 +581,7 @@ c_value_print (struct value *val, struct
/* Note: When we look up RTTI entries, we don't get any information on
const or volatile attributes */
}
- else if (type != value_enclosing_type (val))
+ else if (type != check_typedef (value_enclosing_type (val)))
{
/* No RTTI information, so let's do our best */
fprintf_filtered (stream, "(%s ?) ",
--- /dev/null 1969-12-31 19:00:00.000000000 -0500
+++ testsuite/gdb.base/ptr-typedef.exp 2005-03-06 12:41:52.000000000 -0500
@@ -0,0 +1,41 @@
+# Copyright 2005 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 2 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, write to the Free Software
+# Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+
+if $tracelevel then {
+ strace $tracelevel
+}
+
+set testfile ptr-typedef
+set srcfile ${testfile}.c
+set binfile ${objdir}/${subdir}/${testfile}
+if { [gdb_compile "${srcdir}/${subdir}/${srcfile}" "${binfile}" executable {debug}] != "" } {
+ untested "Couldn't compile test program"
+ return -1
+}
+
+# Get things started.
+
+gdb_exit
+gdb_start
+gdb_reinitialize_dir $srcdir/$subdir
+gdb_load ${binfile}
+
+if ![runto marker1] {
+ untested "Couldn't run to marker1"
+}
+
+gdb_test "print foo_ptr" "\\\$$decimal = \\\(struct foo \\\*\\\) $hex"
+gdb_test "print foz_ptr" "\\\$$decimal = \\\(foz\\\) $hex"
--- /dev/null 1969-12-31 19:00:00.000000000 -0500
+++ testsuite/gdb.base/ptr-typedef.c 2005-03-06 12:35:44.000000000 -0500
@@ -0,0 +1,44 @@
+/* This testcase is part of GDB, the GNU debugger.
+
+ Copyright 2005
+ 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 2 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, write to the Free Software
+ Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
+ USA. */
+
+struct foo {
+ int x;
+};
+
+typedef struct foo *foz;
+
+struct foo *foo_ptr;
+foz foz_ptr;
+
+int
+marker1 (void)
+{
+ return foo_ptr == foz_ptr;
+}
+
+int
+main (void)
+{
+ struct foo the_foo;
+ foo_ptr = &the_foo;
+ foz_ptr = &the_foo;
+
+ return marker1 ();
+}