1# Copyright 2002-2020 Free Software Foundation, Inc.
2
3# This program is free software; you can redistribute it and/or modify
4# it under the terms of the GNU General Public License as published by
5# the Free Software Foundation; either version 3 of the License, or
6# (at your option) any later version.
7#
8# This program is distributed in the hope that it will be useful,
9# but WITHOUT ANY WARRANTY; without even the implied warranty of
10# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
11# GNU General Public License for more details.
12#
13# You should have received a copy of the GNU General Public License
14# along with this program.  If not, see <http://www.gnu.org/licenses/>.
15
16# This file is part of the gdb testsuite
17
18# Test casting, especially between class types or pointer-to-class
19# types.
20
21# This file is part of the gdb testsuite
22
23#
24# test running programs
25#
26
27
28if { [skip_cplus_tests] } { continue }
29
30standard_testfile .cc casts03.cc
31
32if [get_compiler_info "c++"] {
33    return -1
34}
35
36if {[prepare_for_testing "failed to prepare" $testfile $srcfile {debug c++}]} {
37    return -1
38}
39
40if ![runto_main] then {
41    perror "couldn't run to breakpoint"
42    continue
43}
44
45# Prevent symbol on address 0x0 being printed.
46gdb_test_no_output "set print symbol off"
47
48gdb_test "break [gdb_get_line_number "casts.exp: 1"]" \
49    "Breakpoint.*at.* file .*" \
50    ""
51
52gdb_test "continue" "Breakpoint .* at .*casts.cc.*" ""
53
54# Casting a pointer to a base class to a pointer to a derived class
55# should yield the entire derived class.  Until August 2002, GDB got
56# the enclosing type on `(B *) a' wrong: while the value's static type
57# was `B *', as it should be, the enclosing type (which is supposed to
58# be the dynamic type) was `A *'.  It's senseless to have a static
59# type derived from the dynamic type; it should be the other way
60# 'round.  Dereferencing this oddly typed pointer yielded a value in
61# which only the base class's members were initialized, since GDB uses
62# the enclosing type to decide how many bytes to read.  Members from
63# the derived class were garbage, from GDB's address space.
64gdb_test "print * (B *) a" ".* = {<A> = {a = 42}, b = 1729}" \
65    "cast base class pointer to derived class pointer"
66
67# Check also that we get the same results from letting the compiler do
68# the dereference.
69gdb_test "print * b" ".* = {<A> = {a = 42}, b = 1729}" \
70    "let compiler cast base class pointer to derived class pointer"
71
72# Check upcasting (it is trivial but still).
73gdb_test "print * (A *) b" ".* = {a = 42}" \
74    "cast derived class pointer to base class pointer"
75
76# Casting References.
77# Check upcasting.
78gdb_test "print (A &) br" ".* = .A &.* {a = 42}" \
79    "cast derived class reference to base class reference"
80
81# Check downcasting.
82gdb_test "print (B &) ar" ".* = .B.* {<A> = {a = 42}, b = 1729}" \
83    "cast base class reference to derived class reference"
84
85# Check compiler casting
86gdb_test "print br" ".* = .B.* {<A> = {a = 42}, b = 1729}" \
87    "let compiler cast base class reference to derived class reference"
88
89
90# A few basic tests of "new" casts.
91
92gdb_test "print const_cast<const B *> (b)" " = \\(const B \\*\\) $hex" \
93    "basic test of const_cast"
94
95gdb_test "print const_cast<void *> (0)" " = \\(void \\*\\) 0x0" \
96    "const_cast of 0"
97
98gdb_test "print static_cast<A *> (b)" " = \\(A \\*\\) $hex" \
99    "basic test of static_cast"
100
101gdb_test "print static_cast<A &> (*b)" " = \\(A \\&\\) @$hex: {a = 42}" \
102    "static_cast to reference type"
103
104gdb_test "print reinterpret_cast<A *> (b)" " = \\(A \\*\\) $hex" \
105    "basic test of reinterpret_cast"
106
107gdb_test "print reinterpret_cast<void> (b)" "Invalid reinterpret_cast" \
108    "test invalid reinterpret_cast"
109
110gdb_test "print reinterpret_cast<A &> (*b)" " = \\(A \\&\\) @$hex: {a = 42}" \
111    "reinterpret_cast to reference type"
112
113# Basic tests using typeof.
114
115foreach opname {__typeof__ __typeof __decltype} {
116    gdb_test "print (${opname}(a)) (b)" " = \\(A \\*\\) $hex" \
117	"old-style cast using $opname"
118
119    gdb_test "print static_cast<${opname}(a)> (b)" " = \\(A \\*\\) $hex" \
120	"static_cast using $opname"
121
122    gdb_test "print reinterpret_cast<${opname}(a)> (b)" " = \\(A \\*\\) $hex" \
123	"reinterpret_cast using $opname"
124}
125
126gdb_test "whatis __decltype(*a)" "type = A \\&"
127
128# Tests of dynamic_cast.
129
130set nonzero_hex "0x\[0-9A-Fa-f\]\[0-9A-Fa-f\]+"
131
132gdb_test "print dynamic_cast<void> (a)" \
133    ".*must be a pointer or reference type" \
134    "invalid dynamic_cast"
135
136gdb_test "print dynamic_cast<void *> (0)" \
137    " = \\(void \\*\\) 0x0" \
138    "dynamic_cast of 0 to void*"
139
140gdb_test "print dynamic_cast<Alpha *> (&derived)" \
141    " = \\(Alpha \\*\\) $nonzero_hex" \
142    "dynamic_cast simple upcast"
143
144gdb_test "print dynamic_cast<Alpha *> (&doublyderived)" \
145    " = \\(Alpha \\*\\) $nonzero_hex" \
146    "dynamic_cast upcast to unique base"
147
148gdb_test "print dynamic_cast<Alpha &> (derived)" \
149    " = \\(Alpha \\&\\) @$nonzero_hex: {.* = ${nonzero_hex}( <vtable for Derived.*>)?}" \
150    "dynamic_cast simple upcast to reference"
151
152gdb_test "print dynamic_cast<Derived *> (ad)" \
153    " = \\(Derived \\*\\) ${nonzero_hex}( <vtable for Derived.*>)?" \
154    "dynamic_cast simple downcast"
155
156gdb_test "print dynamic_cast<VirtuallyDerived *> (add)" \
157    " = \\(VirtuallyDerived \\*\\) $nonzero_hex" \
158    "dynamic_cast simple downcast to intermediate class"
159
160gdb_test "print dynamic_cast<VirtuallyDerived *> (ad)" \
161    " = \\(VirtuallyDerived \\*\\) 0x0" \
162    "dynamic_cast to non-existing base"
163
164gdb_test "print dynamic_cast<VirtuallyDerived &> (*ad)" \
165    "dynamic_cast failed" \
166    "dynamic_cast to reference to non-existing base"
167
168gdb_test "print dynamic_cast<DoublyDerived *> (add)" \
169    " = \\(DoublyDerived \\*\\) ${nonzero_hex}( <vtable for DoublyDerived.*>)?" \
170    "dynamic_cast unique downcast"
171
172gdb_test "print dynamic_cast<Gamma *> (add)" \
173    " = \\(Gamma \\*\\) $nonzero_hex" \
174    "dynamic_cast to sibling"
175
176if {[prepare_for_testing "failed to prepare" ${testfile}03 $srcfile2 \
177			 {debug c++ additional_flags=-std=c++03}]} {
178    return -1
179}
180
181if ![runto_main] then {
182    perror "couldn't run to breakpoint"
183    continue
184}
185
186# Prevent symbol on address 0x0 being printed.
187gdb_test_no_output "set print symbol off"
188
189gdb_breakpoint [gdb_get_line_number "casts.exp: 1" $srcfile2]
190gdb_continue_to_breakpoint "end of casts03"
191
192# Test that keyword shadowing works.
193
194gdb_test "whatis decltype(5)" " = double"
195