Same _exact_ code in C and D give different results -- why? - c

Question

When I run this C code:
// Get rid of the CRT and stuff; we don't need it
#pragma comment(linker, "/Entry:mainCRTStartup")
#pragma comment(linker, "/NoDefaultLib:msvcrt.lib")
#pragma comment(linker, "/NoDefaultLib:kernel32.lib")
#pragma comment(linker, "/NoDefaultLib:ntdll.lib")
#pragma comment(linker, "/Subsystem:Console")
#pragma comment(lib, "user32.lib")
#include <windows.h>
int mainCRTStartup()
{
MSG msg;
HWND hWndParent;
WNDCLASS wndClass =
{
0, &DefWindowProc, 0, 0, NULL, NULL, LoadCursor(NULL, IDC_ARROW),
GetSysColorBrush(COLOR_3DFACE), NULL, TEXT("MyClass")
};
RegisterClass(&wndClass);
hWndParent = CreateWindow(
wndClass.lpszClassName, NULL, WS_VISIBLE | WS_OVERLAPPEDWINDOW,
0, 0, 33, 100, NULL, NULL, NULL, NULL);
CreateWindow(TEXT("Button"), wndClass.lpszClassName,
WS_VISIBLE | WS_CHILD | BS_GROUPBOX,
5, 5, 100, 50, hWndParent, NULL, NULL, NULL);
while (GetMessage(&msg, hWndParent, 0, 0) > 0)
{
TranslateMessage(&msg);
DispatchMessage(&msg);
}
return 0;
}
I get:
But when I run the equivalent D code:
// Again, get rid of the runtime
pragma(startaddress, mainCRTStartup);
pragma(lib, "dmd_win32.lib");
import win32.windows;
int mainCRTStartup()
{
MSG msg;
HWND hWndParent;
WNDCLASS wndClass =
{
0, &DefWindowProc, 0, 0, NULL, NULL, LoadCursor(NULL, IDC_ARROW),
GetSysColorBrush(COLOR_3DFACE), NULL, "MyClass"
};
RegisterClass(&wndClass);
hWndParent = CreateWindow(
wndClass.lpszClassName, NULL, WS_VISIBLE | WS_OVERLAPPEDWINDOW,
0, 0, 33, 100, NULL, NULL, NULL, NULL);
CreateWindow("Button", wndClass.lpszClassName,
WS_VISIBLE | WS_CHILD | BS_GROUPBOX,
5, 5, 100, 50, hWndParent, NULL, NULL, NULL);
while (GetMessage(&msg, hWndParent, 0, 0) > 0)
{
TranslateMessage(&msg);
DispatchMessage(&msg);
}
return 0;
}
I get:
I'm so confused... what can possibly be causing this white background?!
Edit:
I'm not sure it's actually a library bug... I just removed the dependency (and I don't see anything wrong with the code), but the problem is still there:
version = Unicode;
extern(Windows):
alias void* HWND, HMENU, HINSTANCE, HCURSOR, HBRUSH, HICON;
alias ushort ATOM, WORD;
alias uint UINT, DWORD;
alias int[2] POINT;
alias int BOOL;
alias int LONG;
alias size_t WPARAM, LPARAM, LRESULT;
alias char* LPSTR;
alias const(char)* LPCSTR;
alias wchar* LPWSTR;
alias const(wchar)* LPCWSTR;
version(Unicode)
{
alias LPCWSTR LPCTSTR;
alias LPWSTR LPTSTR;
alias GetMessageW GetMessage;
alias CreateWindowExW CreateWindowEx;
alias DispatchMessageW DispatchMessage;
alias DefWindowProcW DefWindowProc;
alias LoadCursorW LoadCursor;
alias RegisterClassW RegisterClass;
alias WNDCLASSW WNDCLASS;
}
else
{
alias LPCSTR LPCTSTR;
alias LPSTR LPTSTR;
alias GetMessageA GetMessage;
alias CreateWindowExA CreateWindowEx;
alias DispatchMessageA DispatchMessage;
alias DefWindowProcA DefWindowProc;
alias LoadCursorA LoadCursor;
alias RegisterClassA RegisterClass;
alias WNDCLASSA WNDCLASS;
}
LPCTSTR MAKEINTATOM(ATOM atom) { return cast(LPCTSTR)atom; }
ATOM RegisterClassA(WNDCLASSA*);
ATOM RegisterClassW(WNDCLASSW*);
HCURSOR LoadCursorA(HINSTANCE, LPCSTR);
HCURSOR LoadCursorW(HINSTANCE, LPCWSTR);
LRESULT DefWindowProcA(HWND, UINT, WPARAM, LPARAM);
LRESULT DefWindowProcW(HWND, UINT, WPARAM, LPARAM);
BOOL GetMessageA(const(MSG)*, HWND, UINT, UINT);
BOOL GetMessageW(const(MSG)*, HWND, UINT, UINT);
LONG DispatchMessageA(const(MSG)*);
LONG DispatchMessageW(const(MSG)*);
BOOL TranslateMessage(const(MSG)*);
HWND CreateWindowExA(int, LPCSTR, LPCSTR, DWORD, int, int, int, int, HWND, HMENU, HINSTANCE, void*);
HWND CreateWindowExW(int, LPCWSTR, LPCWSTR, DWORD, int, int, int, int, HWND, HMENU, HINSTANCE, void*);
HBRUSH GetSysColorBrush(int);
alias LRESULT function(HWND, UINT, WPARAM, LPARAM) WNDPROC;
enum
{
NULL = null,
COLOR_3DFACE = 15,
BS_GROUPBOX = 7,
}
const LPCTSTR IDC_ARROW = cast(LPCTSTR)32512;
struct MSG
{
HWND hwnd;
UINT message;
WPARAM wParam;
LPARAM lParam;
DWORD time;
POINT pt;
}
struct WNDCLASSA
{
UINT style;
WNDPROC lpfnWndProc;
int cbClsExtra;
int cbWndExtra;
HINSTANCE hInstance;
HICON hIcon;
HCURSOR hCursor;
HBRUSH hbrBackground;
LPCSTR lpszMenuName;
LPCSTR lpszClassName;
}
struct WNDCLASSW
{
UINT style;
WNDPROC lpfnWndProc;
int cbClsExtra;
int cbWndExtra;
HINSTANCE hInstance;
HICON hIcon;
HCURSOR hCursor;
HBRUSH hbrBackground;
LPCWSTR lpszMenuName;
LPCWSTR lpszClassName;
}
enum
{
WS_OVERLAPPED = 0,
WS_TILED = WS_OVERLAPPED,
WS_MAXIMIZEBOX = 0x00010000,
WS_MINIMIZEBOX = 0x00020000,
WS_TABSTOP = 0x00010000,
WS_GROUP = 0x00020000,
WS_THICKFRAME = 0x00040000,
WS_SIZEBOX = WS_THICKFRAME,
WS_SYSMENU = 0x00080000,
WS_HSCROLL = 0x00100000,
WS_VSCROLL = 0x00200000,
WS_DLGFRAME = 0x00400000,
WS_BORDER = 0x00800000,
WS_CAPTION = 0x00c00000,
WS_OVERLAPPEDWINDOW = WS_OVERLAPPED|WS_CAPTION|WS_SYSMENU|WS_THICKFRAME|WS_MINIMIZEBOX|WS_MAXIMIZEBOX,
WS_TILEDWINDOW = WS_OVERLAPPEDWINDOW,
WS_MAXIMIZE = 0x01000000,
WS_CLIPCHILDREN = 0x02000000,
WS_CLIPSIBLINGS = 0x04000000,
WS_DISABLED = 0x08000000,
WS_VISIBLE = 0x10000000,
WS_MINIMIZE = 0x20000000,
WS_ICONIC = WS_MINIMIZE,
WS_CHILD = 0x40000000,
WS_CHILDWINDOW = 0x40000000,
WS_POPUP = 0x80000000,
WS_POPUPWINDOW = WS_POPUP|WS_BORDER|WS_SYSMENU,
}
pragma(startaddress, mainCRTStartup);
int mainCRTStartup()
{
MSG msg;
HWND hWndParent;
WNDCLASS wndClass =
{
0, &DefWindowProc, 0, 0, NULL, NULL, LoadCursor(NULL, IDC_ARROW),
GetSysColorBrush(COLOR_3DFACE), NULL, "MyClass"
};
ATOM atom = RegisterClass(&wndClass);
hWndParent = CreateWindowEx(
0, wndClass.lpszClassName, NULL, WS_VISIBLE | WS_OVERLAPPEDWINDOW,
0, 0, 33, 100, NULL, NULL, NULL, NULL);
CreateWindowEx(0, "Button", wndClass.lpszClassName,
WS_VISIBLE | WS_CHILD | BS_GROUPBOX,
5, 5, 100, 50, hWndParent, NULL, NULL, NULL);
while (GetMessage(&msg, hWndParent, 0, 0) > 0)
{
TranslateMessage(&msg);
DispatchMessage(&msg);
}
return 0;
}
Either I'm doing something wrong, or it's a compiler bug... but even if it's a compiler bug, I still have no idea how something like this can happen, because it would need to call very specific APIs! Ideas?

Answer 1

This is subsystem version issue (linker responsibility). Add -L/SUBSYSTEM:CONSOLE:4.0 to dmd command line to fix MyClass background color. Walter likes old systems so default OPTLINK subsystem version is 3.10. Looks like Microsoft's link 9.0 use 5.0 as default subsystem version.

Answer 2

Linux guy here so I will do my best:
It looks like a problem with the library itself. My guess is you got it from here?
https://github.com/AndrejMitrovic/DWinProgramming
In this case the solution is to contact the fellow who wrote the dmd win32 library you are using. If you compiled them from source then certainly there is a way to contact that person. It appears you have found a bug!
PS: One other possibility if you compiled the libraries from source. You may have a compile argument or flag that is different and causes the difference. Also, perhaps it is a compatibility issue with a library dependency. In this case the answer is still to contact the developer of the library. He will probably ask you for some compile output.