Files
binutils-gdb/gdb/testsuite/gdb.cp/classes.cc
Patrick Frants a43f3893f6 Fix broken recursion detection when printing static members
Recursion detection for static members was broken.  The implementation
uses a growing (and shrinking) obstack object to simulate a stack of
addresses (CORE_ADDR).  Pushing addresses is implemented by calling
obstack_grow(), while popping is implemented by calling obstack_free().
The latter is problematic because obstack_free() expects a pointer to
the base of an object.  When popping elements of the stack however,
obstack_free() was called with the new top, which potentially is not the
same as the base of the stack.  This is unintended use and the effect is
that obstack->next_free and obstack->object_base members are assigned
the value of the new top, which equals an empty stack.  Summary: popping
elements would always result in an empty stack, which breaks the
recursion detection.

The fix shrinks the stack using obstack_blank_fast() with a negative
value as described at the bottom of this page:
https://gcc.gnu.org/onlinedocs/libiberty/Extra-Fast-Growing.html "You
can use obstack_blank_fast with a “negative” size argument to make the
current object smaller.  Just don’t try to shrink it beyond zero
length—there’s no telling what will happen if you do that. Earlier
versions of obstacks allowed you to use obstack_blank to shrink objects.
This will no longer work."

The reproducer is added to gdb.cp/classes.exp, which fails without this
patch.

gdb/ChangeLog:

	* cp-valprint.c (cp_print_value_fields): Use obstack_blank_fast
	to rewind obstack.

gdb/testsuite/ChangeLog:

	* gdb.cp/classes.exp (test_static_members): Test printing
	Outer::instance.
	* gdb.cp/classes.c (struct Inner, struct Outer): New.
	(Inner::instance, Outer::instance): New.
2017-10-26 22:26:08 -04:00

723 lines
13 KiB
C++

/* This testcase is part of GDB, the GNU debugger.
Copyright 1993-2017 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 <http://www.gnu.org/licenses/>. */
// Test various -*- C++ -*- things.
// ====================== basic C++ types =======================
bool v_bool;
bool v_bool_array[2];
typedef struct fleep fleep;
struct fleep { int a; } s;
// ====================== simple class structures =======================
struct default_public_struct {
// defaults to public:
int a;
int b;
};
struct explicit_public_struct {
public:
int a;
int b;
};
struct protected_struct {
protected:
int a;
int b;
};
struct private_struct {
private:
int a;
int b;
};
struct mixed_protection_struct {
public:
int a;
int b;
private:
int c;
int d;
protected:
int e;
int f;
public:
int g;
private:
int h;
protected:
int i;
};
class public_class {
public:
int a;
int b;
};
class protected_class {
protected:
int a;
int b;
};
class default_private_class {
// defaults to private:
int a;
int b;
};
class explicit_private_class {
private:
int a;
int b;
};
class mixed_protection_class {
public:
int a;
int b;
private:
int c;
int d;
protected:
int e;
int f;
public:
int g;
private:
int h;
protected:
int i;
};
class const_vol_method_class {
public:
int a;
int b;
int foo (int &) const;
int bar (int &) volatile;
int baz (int &) const volatile;
};
int const_vol_method_class::foo (int & ir) const
{
return ir + 3;
}
int const_vol_method_class::bar (int & ir) volatile
{
return ir + 4;
}
int const_vol_method_class::baz (int & ir) const volatile
{
return ir + 5;
}
// ========================= simple inheritance ==========================
class A {
public:
int a;
int x;
};
A g_A;
class B : public A {
public:
int b;
int x;
};
B g_B;
class C : public A {
public:
int c;
int x;
};
C g_C;
class D : public B, public C {
public:
int d;
int x;
};
D g_D;
class E : public D {
public:
int e;
int x;
};
E g_E;
class class_with_anon_union
{
public:
int one;
union
{
int a;
long b;
};
};
class_with_anon_union g_anon_union;
void inheritance2 (void)
{
}
void inheritance1 (void)
{
int ival;
int *intp;
// {A::a, A::x}
g_A.A::a = 1;
g_A.A::x = 2;
// {{A::a,A::x},B::b,B::x}
g_B.A::a = 3;
g_B.A::x = 4;
g_B.B::b = 5;
g_B.B::x = 6;
// {{A::a,A::x},C::c,C::x}
g_C.A::a = 7;
g_C.A::x = 8;
g_C.C::c = 9;
g_C.C::x = 10;
// {{{A::a,A::x},B::b,B::x},{{A::a,A::x},C::c,C::x},D::d,D::x}
// The following initialization code is non-portable, but allows us
// to initialize all members of g_D until we can fill in the missing
// initialization code with legal C++ code.
for (intp = (int *) &g_D, ival = 11;
intp < ((int *) &g_D + sizeof (g_D) / sizeof (int));
intp++, ival++)
{
*intp = ival;
}
// Overlay the nonportable initialization with legal initialization.
// ????? = 11; (g_D.A::a = 11; is ambiguous)
// ????? = 12; (g_D.A::x = 12; is ambiguous)
/* djb 6-3-2000
This should take care of it. Rather than try to initialize using an ambiguous
construct, use 2 unambiguous ones for each. Since the ambiguous a/x member is
coming from C, and B, initialize D's C::a, and B::a, and D's C::x and B::x.
*/
g_D.C::a = 15;
g_D.C::x = 12;
g_D.B::a = 11;
g_D.B::x = 12;
g_D.B::b = 13;
g_D.B::x = 14;
// ????? = 15;
// ????? = 16;
g_D.C::c = 17;
g_D.C::x = 18;
g_D.D::d = 19;
g_D.D::x = 20;
// {{{{A::a,A::x},B::b,B::x},{{A::a,A::x},C::c,C::x},D::d,D::x}},E::e,E::x}
// The following initialization code is non-portable, but allows us
// to initialize all members of g_D until we can fill in the missing
// initialization code with legal C++ code.
for (intp = (int *) &g_E, ival = 21;
intp < ((int *) &g_E + sizeof (g_E) / sizeof (int));
intp++, ival++)
{
*intp = ival;
}
// Overlay the nonportable initialization with legal initialization.
// ????? = 21; (g_E.A::a = 21; is ambiguous)
// ????? = 22; (g_E.A::x = 22; is ambiguous)
g_E.B::b = 23;
g_E.B::x = 24;
// ????? = 25;
// ????? = 26;
g_E.C::c = 27;
g_E.C::x = 28;
g_E.D::d = 29;
g_E.D::x = 30;
g_E.E::e = 31;
g_E.E::x = 32;
g_anon_union.one = 1;
g_anon_union.a = 2;
inheritance2 ();
}
// ======================== static member functions =====================
class Static {
public:
static void ii(int, int);
};
void Static::ii (int, int) { }
// ======================== virtual base classes=========================
class vA {
public:
int va;
int vx;
};
vA g_vA;
class vB : public virtual vA {
public:
int vb;
int vx;
};
vB g_vB;
class vC : public virtual vA {
public:
int vc;
int vx;
};
vC g_vC;
class vD : public virtual vB, public virtual vC {
public:
int vd;
int vx;
};
vD g_vD;
class vE : public virtual vD {
public:
int ve;
int vx;
};
vE g_vE;
void inheritance4 (void)
{
}
void inheritance3 (void)
{
int ival;
int *intp;
// {vA::va, vA::vx}
g_vA.vA::va = 1;
g_vA.vA::vx = 2;
// {{vA::va, vA::vx}, vB::vb, vB::vx}
g_vB.vA::va = 3;
g_vB.vA::vx = 4;
g_vB.vB::vb = 5;
g_vB.vB::vx = 6;
// {{vA::va, vA::vx}, vC::vc, vC::vx}
g_vC.vA::va = 7;
g_vC.vA::vx = 8;
g_vC.vC::vc = 9;
g_vC.vC::vx = 10;
// {{{{vA::va, vA::vx}, vB::vb, vB::vx}, vC::vc, vC::vx}, vD::vd,vD::vx}
g_vD.vA::va = 11;
g_vD.vA::vx = 12;
g_vD.vB::vb = 13;
g_vD.vB::vx = 14;
g_vD.vC::vc = 15;
g_vD.vC::vx = 16;
g_vD.vD::vd = 17;
g_vD.vD::vx = 18;
// {{{{{vA::va,vA::vx},vB::vb,vB::vx},vC::vc,vC::vx},vD::vd,vD::vx},vE::ve,vE::vx}
g_vD.vA::va = 19;
g_vD.vA::vx = 20;
g_vD.vB::vb = 21;
g_vD.vB::vx = 22;
g_vD.vC::vc = 23;
g_vD.vC::vx = 24;
g_vD.vD::vd = 25;
g_vD.vD::vx = 26;
g_vE.vE::ve = 27;
g_vE.vE::vx = 28;
inheritance4 ();
}
// ======================================================================
class Base1 {
public:
int x;
Base1(int i) { x = i; }
~Base1 () { }
};
typedef Base1 base1;
class Foo
{
public:
int x;
int y;
static int st;
Foo (int i, int j) { x = i; y = j; }
int operator! ();
operator int ();
int times (int y);
};
typedef Foo ByAnyOtherName;
class Bar : public Base1, public Foo {
public:
int z;
Bar (int i, int j, int k) : Base1 (10*k), Foo (i, j) { z = k; }
};
int Foo::operator! () { return !x; }
int Foo::times (int y) { return x * y; }
int Foo::st = 100;
Foo::operator int() { return x; }
ByAnyOtherName foo(10, 11);
Bar bar(20, 21, 22);
/* Use a typedef for the baseclass to exercise gnu-v3-abi.c:gnuv3_dynamic_class
recursion. It's important that the class itself have no name to make sure
the typedef makes it through to the recursive call. */
typedef class {
public:
int x;
virtual int get_x () { return x; }
} DynamicBase2;
class DynamicBar : public DynamicBase2
{
public:
DynamicBar (int i, int j) { x = i; y = j; }
int y;
};
DynamicBar dynbar (23, 24);
class ClassWithEnum {
public:
enum PrivEnum { red, green, blue, yellow = 42 };
PrivEnum priv_enum;
int x;
};
void enums2 (void)
{
}
/* classes.exp relies on statement order in this function for testing
enumeration fields. */
void enums1 ()
{
ClassWithEnum obj_with_enum;
obj_with_enum.priv_enum = ClassWithEnum::red;
obj_with_enum.x = 0;
enums2 ();
obj_with_enum.priv_enum = ClassWithEnum::green;
obj_with_enum.x = 1;
}
class ClassParam {
public:
int Aptr_a (A *a) { return a->a; }
int Aptr_x (A *a) { return a->x; }
int Aref_a (A &a) { return a.a; }
int Aref_x (A &a) { return a.x; }
int Aval_a (A a) { return a.a; }
int Aval_x (A a) { return a.x; }
};
ClassParam class_param;
class Contains_static_instance
{
public:
int x;
int y;
Contains_static_instance (int i, int j) { x = i; y = j; }
static Contains_static_instance null;
};
Contains_static_instance Contains_static_instance::null(0,0);
Contains_static_instance csi(10,20);
class Contains_nested_static_instance
{
public:
class Nested
{
public:
Nested(int i) : z(i) {}
int z;
static Contains_nested_static_instance xx;
};
Contains_nested_static_instance(int i, int j) : x(i), y(j) {}
int x;
int y;
static Contains_nested_static_instance null;
static Nested yy;
};
Contains_nested_static_instance Contains_nested_static_instance::null(0, 0);
Contains_nested_static_instance::Nested Contains_nested_static_instance::yy(5);
Contains_nested_static_instance
Contains_nested_static_instance::Nested::xx(1,2);
Contains_nested_static_instance cnsi(30,40);
typedef struct {
int one;
int two;
} tagless_struct;
tagless_struct v_tagless;
/* Try to get the compiler to allocate a class in a register. */
class small {
public:
int x;
int method ();
};
int
small::method ()
{
return x + 5;
}
class class_with_typedefs
{
public:
typedef int public_int;
protected:
typedef int protected_int;
private:
typedef int private_int;
public:
class_with_typedefs ()
: public_int_ (1), protected_int_ (2), private_int_ (3) {}
public_int add_public (public_int a) { return a + public_int_; }
public_int add_all (int a)
{ return add_public (a) + add_protected (a) + add_private (a); }
protected:
protected_int add_protected (protected_int a) { return a + protected_int_; }
private:
private_int add_private (private_int a) { return a + private_int_; }
protected:
public_int public_int_;
protected_int protected_int_;
private_int private_int_;
};
class class_with_public_typedef
{
int a;
public:
typedef int INT;
INT b;
};
class class_with_protected_typedef
{
int a;
protected:
typedef int INT;
INT b;
};
class class_with_private_typedef
{
int a;
private:
typedef int INT;
INT b;
};
struct struct_with_public_typedef
{
int a;
public:
typedef int INT;
INT b;
};
struct struct_with_protected_typedef
{
int a;
protected:
typedef int INT;
INT b;
};
struct struct_with_private_typedef
{
int a;
private:
typedef int INT;
INT b;
};
void marker_reg1 () {}
int
register_class ()
{
/* We don't call any methods for v, so gcc version cygnus-2.3.3-930220
might put this variable in a register. This is a lose, though, because
it means that GDB can't call any methods for that variable. */
register small v;
int i;
/* Perform a computation sufficiently complicated that optimizing compilers
won't optimized out the variable. If some compiler constant-folds this
whole loop, maybe using a parameter to this function here would help. */
v.x = 0;
for (i = 0; i < 13; ++i)
v.x += i;
--v.x; /* v.x is now 77 */
marker_reg1 ();
return v.x + 5;
}
void dummy()
{
v_bool = true;
v_bool_array[0] = false;
v_bool_array[1] = v_bool;
}
void use_methods ()
{
/* Refer to methods so that they don't get optimized away. */
int i;
i = class_param.Aptr_a (&g_A);
i = class_param.Aptr_x (&g_A);
i = class_param.Aref_a (g_A);
i = class_param.Aref_x (g_A);
i = class_param.Aval_a (g_A);
i = class_param.Aval_x (g_A);
base1 b (3);
}
struct Inner
{
static Inner instance;
};
struct Outer
{
Inner inner;
static Outer instance;
};
Inner Inner::instance;
Outer Outer::instance;
int
main()
{
dummy();
inheritance1 ();
inheritance3 ();
enums1 ();
register_class ();
/* FIXME: pmi gets optimized out. Need to do some more computation with
it or something. (No one notices, because the test is xfail'd anyway,
but that probably won't always be true...). */
int Foo::* pmi = &Foo::y;
/* Make sure the AIX linker doesn't remove the variable. */
v_tagless.one = 5;
use_methods ();
return foo.*pmi;
}
/* Create an instance for some classes, otherwise they get optimized away. */
default_public_struct default_public_s;
explicit_public_struct explicit_public_s;
protected_struct protected_s;
private_struct private_s;
mixed_protection_struct mixed_protection_s;
public_class public_c;
protected_class protected_c;
default_private_class default_private_c;
explicit_private_class explicit_private_c;
mixed_protection_class mixed_protection_c;
class_with_typedefs class_with_typedefs_c;
class_with_public_typedef class_with_public_typedef_c;
class_with_protected_typedef class_with_protected_typedef_c;
class_with_private_typedef class_with_private_typedef_c;
struct_with_public_typedef struct_with_public_typedef_s;
struct_with_protected_typedef struct_with_protected_typedef_s;
struct_with_private_typedef struct_with_private_typedef_s;