gdb/testsuite/gdb.cp/casts.exp

   1 # Copyright 2002-2004, 2007-2012 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 if $tracelevel then {
  24         strace $tracelevel
  25         }
  26
  27 #
  28 # test running programs
  29 #
  30
  31
  32 if { [skip_cplus_tests] } { continue }
  33
  34 set testfile "casts"
  35 set srcfile ${testfile}.cc
  36 set binfile ${objdir}/${subdir}/${testfile}
  37
  38 if [get_compiler_info ${binfile} "c++"] {
  39     return -1;
  40 }
  41
  42 if  { [gdb_compile "${srcdir}/${subdir}/${srcfile}" "${binfile}" executable {debug c++}] != "" } {
  43      untested casts.exp
  44      return -1
  45 }
  46
  47
  48 gdb_exit
  49 gdb_start
  50 gdb_reinitialize_dir $srcdir/$subdir
  51 gdb_load ${binfile}
  52
  53 if ![runto_main] then {
  54     perror "couldn't run to breakpoint"
  55     continue
  56 }
  57
  58 gdb_test "break [gdb_get_line_number "casts.exp: 1"]" \
  59     "Breakpoint.*at.* file .*" \
  60     ""
  61
  62 gdb_test "continue" "Breakpoint .* at .*casts.cc.*" ""
  63
  64 # Casting a pointer to a base class to a pointer to a derived class
  65 # should yield the entire derived class.  Until August 2002, GDB got
  66 # the enclosing type on `(B *) a' wrong: while the value's static type
  67 # was `B *', as it should be, the enclosing type (which is supposed to
  68 # be the dynamic type) was `A *'.  It's senseless to have a static
  69 # type derived from the dynamic type; it should be the other way
  70 # 'round.  Dereferencing this oddly typed pointer yielded a value in
  71 # which only the base class's members were initialized, since GDB uses
  72 # the enclosing type to decide how many bytes to read.  Members from
  73 # the derived class were garbage, from GDB's address space.
  74 gdb_test "print * (B *) a" ".* = {<A> = {a = 42}, b = 1729}" \
  75     "cast base class pointer to derived class pointer"
  76
  77 # Check also that we get the same results from letting the compiler do
  78 # the dereference.
  79 gdb_test "print * b" ".* = {<A> = {a = 42}, b = 1729}" \
  80     "let compiler cast base class pointer to derived class pointer"
  81
  82 # Check upcasting (it is trivial but still).
  83 gdb_test "print * (A *) b" ".* = {a = 42}" \
  84     "cast derived class pointer to base class pointer"
  85
  86 # Casting References.
  87 # Check upcasting.
  88 gdb_test "print (A &) br" ".* = .A &.* {a = 42}" \
  89     "cast derived class reference to base class reference"
  90
  91 # Check downcasting.
  92 gdb_test "print (B &) ar" ".* = .B.* {<A> = {a = 42}, b = 1729}" \
  93     "cast base class reference to derived class reference"
  94
  95 # Check compiler casting
  96 gdb_test "print br" ".* = .B.* {<A> = {a = 42}, b = 1729}" \
  97     "let compiler cast base class reference to derived class reference"
  98
  99
 100 # A few basic tests of "new" casts.
 101
 102 gdb_test "print const_cast<const B *> (b)" " = \\(const B \\*\\) $hex" \
 103     "basic test of const_cast"
 104
 105 gdb_test "print const_cast<void *> (0)" " = \\(void \\*\\) 0x0" \
 106     "const_cast of 0"
 107
 108 gdb_test "print static_cast<A *> (b)" " = \\(A \\*\\) $hex" \
 109     "basic test of static_cast"
 110
 111 gdb_test "print static_cast<A &> (*b)" " = \\(A \\&\\) @$hex: {a = 42}" \
 112     "static_cast to reference type"
 113
 114 gdb_test "print reinterpret_cast<A *> (b)" " = \\(A \\*\\) $hex" \
 115     "basic test of reinterpret_cast"
 116
 117 gdb_test "print reinterpret_cast<void> (b)" "Invalid reinterpret_cast" \
 118     "test invalid reinterpret_cast"
 119
 120 gdb_test "print reinterpret_cast<A &> (*b)" " = \\(A \\&\\) @$hex: {a = 42}" \
 121     "reinterpret_cast to reference type"
 122
 123 # Tests of dynamic_cast.
 124
 125 set nonzero_hex "0x\[0-9A-Fa-f\]\[0-9A-Fa-f\]+"
 126
 127 gdb_test "print dynamic_cast<void> (a)" \
 128     ".*must be a pointer or reference type" \
 129     "invalid dynamic_cast"
 130
 131 gdb_test "print dynamic_cast<void *> (0)" \
 132     " = \\(void \\*\\) 0x0" \
 133     "dynamic_cast of 0 to void*"
 134
 135 gdb_test "print dynamic_cast<Alpha *> (&derived)" \
 136     " = \\(Alpha \\*\\) $nonzero_hex" \
 137     "dynamic_cast simple upcast"
 138
 139 gdb_test "print dynamic_cast<Alpha *> (&doublyderived)" \
 140     " = \\(Alpha \\*\\) $nonzero_hex" \
 141     "dynamic_cast upcast to unique base"
 142
 143 gdb_test "print dynamic_cast<Alpha &> (derived)" \
 144     " = \\(Alpha \\&\\) @$nonzero_hex: {.* = $nonzero_hex}" \
 145     "dynamic_cast simple upcast to reference"
 146
 147 gdb_test "print dynamic_cast<Derived *> (ad)" \
 148     " = \\(Derived \\*\\) $nonzero_hex" \
 149     "dynamic_cast simple downcast"
 150
 151 gdb_test "print dynamic_cast<VirtuallyDerived *> (add)" \
 152     " = \\(VirtuallyDerived \\*\\) $nonzero_hex" \
 153     "dynamic_cast simple downcast to intermediate class"
 154
 155 gdb_test "print dynamic_cast<VirtuallyDerived *> (ad)" \
 156     " = \\(VirtuallyDerived \\*\\) 0x0" \
 157     "dynamic_cast to non-existing base"
 158
 159 gdb_test "print dynamic_cast<VirtuallyDerived &> (*ad)" \
 160     "dynamic_cast failed" \
 161     "dynamic_cast to reference to non-existing base"
 162
 163 gdb_test "print dynamic_cast<DoublyDerived *> (add)" \
 164     " = \\(DoublyDerived \\*\\) $nonzero_hex" \
 165     "dynamic_cast unique downcast"
 166
 167 gdb_test "print dynamic_cast<Gamma *> (add)" \
 168     " = \\(Gamma \\*\\) $nonzero_hex" \
 169     "dynamic_cast to sibling"