g_pd3DDeviceが定義されていません

少し前と似たような質問なのですが、

C++
1include<windows.h>
2#include<d3dx9.h>
3#include<d3d9.h>
4
5LRESULT CALLBACK WndProc(HWND hwnd, UINT msg, WPARAM wp, LPARAM lp) {
6	switch (msg) {
7	case WM_DESTROY:
8		PostQuitMessage(0);
9		return 0;
10	}
11	return DefWindowProc(hwnd, msg, wp, lp);
12}
13
14int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance,
15	PSTR lpCmdLine, int nCmdShow) {
16	HWND hwnd;
17	MSG msg;
18	WNDCLASS winc;
19	RECT rw, rc;
20	D3DPRESENT_PARAMETERS d3dpp;
21	LPDIRECT3D9 g_pD3D = NULL;
22	winc.style = CS_HREDRAW | CS_VREDRAW;
23	winc.lpfnWndProc = WndProc;
24	winc.cbClsExtra = winc.cbWndExtra = 0;
25	winc.hInstance = hInstance;
26	winc.hIcon = LoadIcon(NULL, IDI_APPLICATION);
27	winc.hCursor = LoadCursor(NULL, IDC_ARROW);
28	winc.hbrBackground = (HBRUSH)GetStockObject(WHITE_BRUSH);
29	winc.lpszMenuName = NULL;
30	winc.lpszClassName = TEXT("Window");
31
32	if (!RegisterClass(&winc)) return 0;
33
34	hwnd = CreateWindow(
35		TEXT("Wndows"), TEXT("TestWindow"),
36		WS_OVERLAPPEDWINDOW | WS_VISIBLE,
37		175, 50, 1920, 1080, NULL, NULL,
38		hInstance, NULL
39	);
40	GetWindowRect(hwnd, &rw); // ウィンドウ全体のサイズ
41	GetClientRect(hwnd, &rc); // クライアント領域のサイズ
42	int new_width = (rw.right - rw.left) - (rc.right - rc.left) + 1280;
43	int new_height = (rw.bottom - rw.top) - (rc.bottom - rc.top) + 720;
44	SetWindowPos(hwnd, NULL, 0, 0, new_width, new_height, SWP_NOMOVE | SWP_NOZORDER);
45	if (hwnd == NULL) return 0;
46
47	if (NULL == (g_pD3D = Direct3DCreate9(D3D_SDK_VERSION)))
48		return E_FAIL;
49
50	ZeroMemory(&d3dpp, sizeof(d3dpp));
51	d3dpp.Windowed = TRUE;
52	d3dpp.SwapEffect = D3DSWAPEFFECT_DISCARD;
53	d3dpp.BackBufferFormat = D3DFMT_UNKNOWN;
54
55	if (FAILED(g_pD3D->CreateDevice(D3DADAPTER_DEFAULT, D3DDEVTYPE_HAL, hwnd,
56		D3DCREATE_SOFTWARE_VERTEXPROCESSING,
57		&d3dpp, &g_pd3dDevice)))
58
59	while (GetMessage(&msg, NULL, 0, 0)) DispatchMessage(&msg);
60	return msg.wParam;
61}

一番最後のif文で
if (FAILED(g_pD3D->CreateDevice(D3DADAPTER_DEFAULT, D3DDEVTYPE_HAL, hwnd,
D3DCREATE_SOFTWARE_VERTEXPROCESSING,
&d3dpp, &g_pd3dDevice)))
とあります。
この、FAILEDの部分に赤波線が出ており
エラー内容は「g_pd3DDeviceが定義されていません」
だそうです。

よくわかりません...

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