# Copyright 2002-2014 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 3 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, see . # This file is part of the gdb testsuite # Test casting, especially between class types or pointer-to-class # types. # This file is part of the gdb testsuite # # test running programs # if { [skip_cplus_tests] } { continue } standard_testfile .cc if [get_compiler_info "c++"] { return -1 } if {[prepare_for_testing $testfile.exp $testfile $srcfile {debug c++}]} { return -1 } if ![runto_main] then { perror "couldn't run to breakpoint" continue } # Prevent symbol on address 0x0 being printed. gdb_test_no_output "set print symbol off" gdb_test "break [gdb_get_line_number "casts.exp: 1"]" \ "Breakpoint.*at.* file .*" \ "" gdb_test "continue" "Breakpoint .* at .*casts.cc.*" "" # Casting a pointer to a base class to a pointer to a derived class # should yield the entire derived class. Until August 2002, GDB got # the enclosing type on `(B *) a' wrong: while the value's static type # was `B *', as it should be, the enclosing type (which is supposed to # be the dynamic type) was `A *'. It's senseless to have a static # type derived from the dynamic type; it should be the other way # 'round. Dereferencing this oddly typed pointer yielded a value in # which only the base class's members were initialized, since GDB uses # the enclosing type to decide how many bytes to read. Members from # the derived class were garbage, from GDB's address space. gdb_test "print * (B *) a" ".* = { = {a = 42}, b = 1729}" \ "cast base class pointer to derived class pointer" # Check also that we get the same results from letting the compiler do # the dereference. gdb_test "print * b" ".* = { = {a = 42}, b = 1729}" \ "let compiler cast base class pointer to derived class pointer" # Check upcasting (it is trivial but still). gdb_test "print * (A *) b" ".* = {a = 42}" \ "cast derived class pointer to base class pointer" # Casting References. # Check upcasting. gdb_test "print (A &) br" ".* = .A &.* {a = 42}" \ "cast derived class reference to base class reference" # Check downcasting. gdb_test "print (B &) ar" ".* = .B.* { = {a = 42}, b = 1729}" \ "cast base class reference to derived class reference" # Check compiler casting gdb_test "print br" ".* = .B.* { = {a = 42}, b = 1729}" \ "let compiler cast base class reference to derived class reference" # A few basic tests of "new" casts. gdb_test "print const_cast (b)" " = \\(const B \\*\\) $hex" \ "basic test of const_cast" gdb_test "print const_cast (0)" " = \\(void \\*\\) 0x0" \ "const_cast of 0" gdb_test "print static_cast (b)" " = \\(A \\*\\) $hex" \ "basic test of static_cast" gdb_test "print static_cast (*b)" " = \\(A \\&\\) @$hex: {a = 42}" \ "static_cast to reference type" gdb_test "print reinterpret_cast (b)" " = \\(A \\*\\) $hex" \ "basic test of reinterpret_cast" gdb_test "print reinterpret_cast (b)" "Invalid reinterpret_cast" \ "test invalid reinterpret_cast" gdb_test "print reinterpret_cast (*b)" " = \\(A \\&\\) @$hex: {a = 42}" \ "reinterpret_cast to reference type" # Test that keyword shadowing works. gdb_test "whatis decltype(5)" " = double" # Basic tests using typeof. foreach opname {__typeof__ __typeof __decltype} { gdb_test "print (${opname}(a)) (b)" " = \\(A \\*\\) $hex" \ "old-style cast using $opname" gdb_test "print static_cast<${opname}(a)> (b)" " = \\(A \\*\\) $hex" \ "static_cast using $opname" gdb_test "print reinterpret_cast<${opname}(a)> (b)" " = \\(A \\*\\) $hex" \ "reinterpret_cast using $opname" } gdb_test "whatis __decltype(*a)" "type = A \\&" # Tests of dynamic_cast. set nonzero_hex "0x\[0-9A-Fa-f\]\[0-9A-Fa-f\]+" gdb_test "print dynamic_cast (a)" \ ".*must be a pointer or reference type" \ "invalid dynamic_cast" gdb_test "print dynamic_cast (0)" \ " = \\(void \\*\\) 0x0" \ "dynamic_cast of 0 to void*" gdb_test "print dynamic_cast (&derived)" \ " = \\(Alpha \\*\\) $nonzero_hex" \ "dynamic_cast simple upcast" gdb_test "print dynamic_cast (&doublyderived)" \ " = \\(Alpha \\*\\) $nonzero_hex" \ "dynamic_cast upcast to unique base" gdb_test "print dynamic_cast (derived)" \ " = \\(Alpha \\&\\) @$nonzero_hex: {.* = ${nonzero_hex}( )?}" \ "dynamic_cast simple upcast to reference" gdb_test "print dynamic_cast (ad)" \ " = \\(Derived \\*\\) ${nonzero_hex}( )?" \ "dynamic_cast simple downcast" gdb_test "print dynamic_cast (add)" \ " = \\(VirtuallyDerived \\*\\) $nonzero_hex" \ "dynamic_cast simple downcast to intermediate class" gdb_test "print dynamic_cast (ad)" \ " = \\(VirtuallyDerived \\*\\) 0x0" \ "dynamic_cast to non-existing base" gdb_test "print dynamic_cast (*ad)" \ "dynamic_cast failed" \ "dynamic_cast to reference to non-existing base" gdb_test "print dynamic_cast (add)" \ " = \\(DoublyDerived \\*\\) ${nonzero_hex}( )?" \ "dynamic_cast unique downcast" gdb_test "print dynamic_cast (add)" \ " = \\(Gamma \\*\\) $nonzero_hex" \ "dynamic_cast to sibling"