gdb/testsuite/gdb.cp/casts.exp

   1 # Copyright 2002, 2003, 2004, 2007, 2008, 2009, 2010
   2 # Free Software Foundation, Inc.
   3
   4 # This program is free software; you can redistribute it and/or modify
   5 # it under the terms of the GNU General Public License as published by
   6 # the Free Software Foundation; either version 3 of the License, or
   7 # (at your option) any later version.
   8 #
   9 # This program is distributed in the hope that it will be useful,
  10 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 # GNU General Public License for more details.
  13 #
  14 # You should have received a copy of the GNU General Public License
  15 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
  16
  17 # This file is part of the gdb testsuite
  18
  19 # Test casting, especially between class types or pointer-to-class
  20 # types.
  21
  22 # This file is part of the gdb testsuite
  23
  24 if $tracelevel then {
  25         strace $tracelevel
  26         }
  27
  28 #
  29 # test running programs
  30 #
  31
  32 set prms_id 0
  33 set bug_id 0
  34
  35 if { [skip_cplus_tests] } { continue }
  36
  37 set testfile "casts"
  38 set srcfile ${testfile}.cc
  39 set binfile ${objdir}/${subdir}/${testfile}
  40
  41 if [get_compiler_info ${binfile} "c++"] {
  42     return -1;
  43 }
  44
  45 if  { [gdb_compile "${srcdir}/${subdir}/${srcfile}" "${binfile}" executable {debug c++}] != "" } {
  46      untested casts.exp
  47      return -1
  48 }
  49
  50
  51 gdb_exit
  52 gdb_start
  53 gdb_reinitialize_dir $srcdir/$subdir
  54 gdb_load ${binfile}
  55
  56 if ![runto_main] then {
  57     perror "couldn't run to breakpoint"
  58     continue
  59 }
  60
  61 gdb_test "break [gdb_get_line_number "casts.exp: 1"]" \
  62     "Breakpoint.*at.* file .*" \
  63     ""
  64
  65 gdb_test "continue" "Breakpoint .* at .*casts.cc.*" ""
  66
  67 # Casting a pointer to a base class to a pointer to a derived class
  68 # should yield the entire derived class.  Until August 2002, GDB got
  69 # the enclosing type on `(B *) a' wrong: while the value's static type
  70 # was `B *', as it should be, the enclosing type (which is supposed to
  71 # be the dynamic type) was `A *'.  It's senseless to have a static
  72 # type derived from the dynamic type; it should be the other way
  73 # 'round.  Dereferencing this oddly typed pointer yielded a value in
  74 # which only the base class's members were initialized, since GDB uses
  75 # the enclosing type to decide how many bytes to read.  Members from
  76 # the derived class were garbage, from GDB's address space.
  77 gdb_test "print * (B *) a" ".* = {<A> = {a = 42}, b = 1729}" \
  78     "cast base class pointer to derived class pointer"
  79
  80 # Check also that we get the same results from letting the compiler do
  81 # the dereference.
  82 gdb_test "print * b" ".* = {<A> = {a = 42}, b = 1729}" \
  83     "let compiler cast base class pointer to derived class pointer"
  84
  85 # Check upcasting (it is trivial but still).
  86 gdb_test "print * (A *) b" ".* = {a = 42}" \
  87     "cast derived class pointer to base class pointer"
  88
  89 # Casting References.
  90 # Check upcasting.
  91 gdb_test "print (A &) br" ".* = .A &.* {a = 42}" \
  92     "cast derived class reference to base class reference"
  93
  94 # Check downcasting.
  95 gdb_test "print (B &) ar" ".* = .B.* {<A> = {a = 42}, b = 1729}" \
  96     "cast base class reference to derived class reference"
  97
  98 # Check compiler casting
  99 gdb_test "print br" ".* = .B.* {<A> = {a = 42}, b = 1729}" \
 100     "let compiler cast base class reference to derived class reference"
 101
 102
 103 # A few basic tests of "new" casts.
 104
 105 gdb_test "print const_cast<const B *> (b)" " = \\(const B \\*\\) $hex" \
 106     "basic test of const_cast"
 107
 108 gdb_test "print const_cast<void *> (0)" " = \\(void \\*\\) 0x0" \
 109     "const_cast of 0"
 110
 111 gdb_test "print static_cast<A *> (b)" " = \\(A \\*\\) $hex" \
 112     "basic test of static_cast"
 113
 114 gdb_test "print static_cast<A &> (*b)" " = \\(A \\&\\) @$hex: {a = 42}" \
 115     "static_cast to reference type"
 116
 117 gdb_test "print reinterpret_cast<A *> (b)" " = \\(A \\*\\) $hex" \
 118     "basic test of reinterpret_cast"
 119
 120 gdb_test "print reinterpret_cast<void> (b)" "Invalid reinterpret_cast" \
 121     "test invalid reinterpret_cast"
 122
 123 gdb_test "print reinterpret_cast<A &> (*b)" " = \\(A \\&\\) @$hex: {a = 42}" \
 124     "reinterpret_cast to reference type"
 125
 126 # Tests of dynamic_cast.
 127
 128 set nonzero_hex "0x\[0-9A-Fa-f\]\[0-9A-Fa-f\]+"
 129
 130 gdb_test "print dynamic_cast<void> (a)" \
 131     ".*must be a pointer or reference type" \
 132     "invalid dynamic_cast"
 133
 134 gdb_test "print dynamic_cast<void *> (0)" \
 135     " = \\(void \\*\\) 0x0" \
 136     "dynamic_cast of 0 to void*"
 137
 138 gdb_test "print dynamic_cast<Alpha *> (&derived)" \
 139     " = \\(Alpha \\*\\) $nonzero_hex" \
 140     "dynamic_cast simple upcast"
 141
 142 gdb_test "print dynamic_cast<Alpha *> (&doublyderived)" \
 143     " = \\(Alpha \\*\\) $nonzero_hex" \
 144     "dynamic_cast upcast to unique base"
 145
 146 gdb_test "print dynamic_cast<Alpha &> (derived)" \
 147     " = \\(Alpha \\&\\) @$nonzero_hex: {.* = $nonzero_hex}" \
 148     "dynamic_cast simple upcast to reference"
 149
 150 gdb_test "print dynamic_cast<Derived *> (ad)" \
 151     " = \\(Derived \\*\\) $nonzero_hex" \
 152     "dynamic_cast simple downcast"
 153
 154 gdb_test "print dynamic_cast<VirtuallyDerived *> (add)" \
 155     " = \\(VirtuallyDerived \\*\\) $nonzero_hex" \
 156     "dynamic_cast simple downcast to intermediate class"
 157
 158 gdb_test "print dynamic_cast<VirtuallyDerived *> (ad)" \
 159     " = \\(VirtuallyDerived \\*\\) 0x0" \
 160     "dynamic_cast to non-existing base"
 161
 162 gdb_test "print dynamic_cast<VirtuallyDerived &> (*ad)" \
 163     "dynamic_cast failed" \
 164     "dynamic_cast to reference to non-existing base"
 165
 166 gdb_test "print dynamic_cast<DoublyDerived *> (add)" \
 167     " = \\(DoublyDerived \\*\\) $nonzero_hex" \
 168     "dynamic_cast unique downcast"
 169
 170 gdb_test "print dynamic_cast<Gamma *> (add)" \
 171     " = \\(Gamma \\*\\) $nonzero_hex" \
 172     "dynamic_cast to sibling"