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// { dg-do run }
// PRMS Id: 6275
// Bug: unification fails for call to find_parameter_in_stack.
#include <stdio.h>
#include <stdlib.h>
const int max_stack_size = 20;
template <class T>
class Stack {
private:
T objects[max_stack_size];
int nobjects;
public:
Stack(): nobjects(0) {}
void push(const T&a) {
if (nobjects >= max_stack_size) {
fprintf(stderr,"Stack: overflow\n");
abort();
}
objects[nobjects++] = a;
}
T pop() {
if (!nobjects) {
fprintf(stderr,"Stack: underflow\n");
abort();
}
nobjects -= 1;
T result = objects[nobjects];
return result;
}
T top() const {
if (!nobjects) {
fprintf(stderr,"Stack: underflow\n");
abort();
}
return objects[nobjects - 1];
}
int n() const { return nobjects; }
T operator[](int i) { return objects[i]; }
};
template <class T>
class Parameter {
T parameter_;
int is_set_;
int overrides_;
public:
Parameter(): is_set_(0), overrides_(0) {}
void set(const T& a) { parameter_ = a; is_set_ = 1; }
void override(int overrides = 1) { overrides_ = overrides; }
const T& value() const { return parameter_; }
int overrides() const { return overrides_; }
int is_set() const { return is_set_; }
};
template <class T1, class T2>
T2
find_parameter_in_stack(Stack<T1>& stack, Parameter<T2>& (T1::*access)())
{
T2 result;
int have_result = 0;
for (int i=stack.n()-1; i>=0; i--) {
if ((stack[i].*access)().is_set()) {
if (!have_result || (stack[i].*access)().overrides()) {
result = (stack[i].*access)().value();
have_result = 1;
}
}
}
return result;
}
class A {
private:
Parameter<int> a_;
public:
A() { }
Parameter<int>& a() { return a_; }
};
int
main(int, char**)
{
Stack<A> A_stack;
A a1;
A a2;
a1.a().set(1);
a2.a().set(2);
A_stack.push(a1);
A_stack.push(a2);
int val = find_parameter_in_stack(A_stack, &A::a);
printf("val = %d\n", val);
if (val != 2)
return 1;
A_stack.pop();
A_stack.pop();
a1.a().override();
A_stack.push(a1);
A_stack.push(a2);
val = find_parameter_in_stack(A_stack, &A::a);
printf("val = %d\n", val);
if (val != 1)
return 1;
return 0;
}
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