Exception Error C++ //Visual Studio [closed] - c++

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So im creating an engine from scrath(learnign purposes).
And when i test my TArray i get an Execption thrown in my Memory.h file. This happens only when im trying to test the TArray
Here is my code for TArray.h
#pragma once
#include "Memory/DynamicLinearStackAllocator.h"
template <typename T, typename Allocator = DynamicLinearStackAllocator>
class TArray
{
private:
Allocator m_Allocator;
uint32 m_ElementCount;
public:
FORCEINLINE TArray()
{
}
FORCEINLINE ~TArray()
{
m_Allocator.Destroy();
}
FORCEINLINE TArray(const uint32 InElementCount)
{
m_Allocator.Resize<T>(InElementCount, m_ElementCount);
m_ElementCount = InElementCount;
}
FORCEINLINE void Add(const T &InValue)
{
}
FORCEINLINE T* GetData() const { return m_Allocator.GetAllocator<T>(); }
FORCEINLINE uint32 Num() const
{
return m_ElementCount;
}
FORCEINLINE T& operator[](uint32 InElementIndex) const
{
check(m_ElementCount > InElementIndex);
return GetData()[InElementIndex];
}
};
namespace Tests
{
FORCEINLINE void TestArrays()
{
{
TArray<float> data(10);
check(data.Num() == 10);
for(uint32 i = 0; i < data.Num(); i++)
{
data[i] = 2.0f;
}
check(data[0] == 2.0f);
}
{
TArray<uint32> data(5);
data[0] = 10;
data[1] = 5;
check(data.Num() == 5);
check(data[0] == 10);
check(data[1] == 5);
}
{
TArray<float> data(1);
data[2] = 2.0f;
}
}
}
When i try to compile(Im using Visual Studio 2017) it gives me an execption error at this position in Memory.h
static void* Copy(void *InDestination, const void *InSource, size_t InSize)
{
check_slow(InDestination);
check_slow(InSource);
check_slow(InSize > 0);
return memcpy(InDestination, InSource, InSize);
}
The test is getting called in the main function with this code:
int main()
{
Tests::TestAssertion();
Tests::TestMemory();
Tests::TestAllocator();
Tests::TestArrays();
return 0;
}
my goal currently is to look if the logger shows me the error here:
{
TArray<float> data(1);
data[2] = 2.0f;
}
here is a screenshot of the full error https://gyazo.com/6c1d6779623ffea97504f5b23f9fd7da
edit: here is the code for the allocator
#pragma once
#include <malloc.h>
#include "Core.h"
#define MEMORY_ALIGMENT 16
struct Memory
{
// TODO:Rework types.
static void* Allocate(const int32 InCount, const size_t InSize)
{
check_slow(InCount > 0);
check_slow(InSize > 0);
const size_t size = InSize * InCount;
return _aligned_malloc(size, MEMORY_ALIGMENT);
}
static void Free(void *InBlock)
{
check_slow(InBlock);
_aligned_free(InBlock);
}
static void* Copy(void *InDestination, const void *InSource, size_t InSize)
{
check_slow(InDestination);
check_slow(InSource);
check_slow(InSize > 0);
return memcpy(InDestination, InSource, InSize);
}
};
void* operator new (size_t InSize)
{
return Memory::Allocate(1, InSize);
}
void operator delete (void* InBlock)
{
Memory::Free(InBlock);
}
namespace Tests
{
struct MemoryTestStruct
{
uint32 p0;
uint32 p1;
uint32 p2;
uint32 p3;
};
FORCEINLINE void TestMemory()
{
MemoryTestStruct *t = new MemoryTestStruct();
check(t);
delete t;
}
}
edit2: Here is the code for the StackAlloctor
#pragma once
#include "../Core.h"
class DynamicLinearStackAllocator
{
private:
void *m_Data;
public:
template <typename T>
FORCEINLINE void Resize(const uint32 InElementCount, const uint32 InPreviousElementCount)
{
void *temp = Memory::Allocate(InElementCount, sizeof(T));
if (InPreviousElementCount > 0)
{
const SIZE_T size = sizeof(T) * InPreviousElementCount;
Memory::Copy(temp, m_Data, size);
Memory::Free(m_Data);
}
m_Data = temp;
}
template <typename T>
FORCEINLINE T* GetAllocator() const
{
return (T*)m_Data;
}
FORCEINLINE void Destroy()
{
Memory::Free(m_Data);
}
};
namespace Tests
{
FORCEINLINE void TestAllocator()
{
DynamicLinearStackAllocator alloc;
alloc.Resize<float>(2, 0);
alloc.Destroy();
}
}

Answer 1

You're not showing the code for your Allocator, but the problem is probably this line in your TArray constructor:
m_Allocator.Resize<T>(InElementCount, m_ElementCount);
At this point, m_ElementCount has not been initialized and will have some random value in it. Resize is then probably trying to free up memory that hasn't been allocated (because of the uninitialized value in m_ElementCount). You should pass in a 0 for the second parameter of the Resize call in your constructor
m_Allocator.Resize<T>(InElementCount, 0);
since there is no existing allocated memory to free.
Also, your default constructor for TArray should initialize m_Allocator.m_data to nullptr (or add a default constructor to DynamicLinearStackAllocator to do that) and set m_ElementCount to 0.