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