make it build with -Wconversion

14 files changed, 62 insertions, 79 deletions

diff --git a/Makefile.mingw b/Makefile.mingw
index 043bce3..e80648a 100644
--- a/Makefile.mingw
+++ b/Makefile.mingw
@@ -2,8 +2,8 @@
 
 CC = i686-w64-mingw32-gcc
 CXX = i686-w64-mingw32-c++
-CFLAGS = -std=c99 -Wall -Wextra -mwindows -municode -DUNICODE -D_UNICODE -gstabs
-CXXFLAGS = -std=c++98 -Wall -Wextra -mwindows -municode -DUNICODE -D_UNICODE -fno-exceptions -fno-rtti -gstabs
+CFLAGS = -std=c99 -Wall -Wextra -Wconversion -mwindows -municode -DUNICODE -D_UNICODE -gstabs
+CXXFLAGS = -std=c++98 -Wall -Wextra -Wconversion -Wsign-conversion -mwindows -municode -DUNICODE -D_UNICODE -fno-exceptions -fno-rtti -gstabs
 LDFLAGS = -luser32 -lcomctl32 -lshell32 -lversion -static
 
 all: out/widgetfactory.exe out/alf/alf.c out/widgetfactory-c.exe
diff --git a/alf/alf.cpp b/alf/alf.cpp
index de8d9c3..b446b33 100644
--- a/alf/alf.cpp
+++ b/alf/alf.cpp
@@ -33,7 +33,7 @@ ALF_DestroyWindowPriv(ALFWindowPriv *priv)
 int
 ALF_CentipointsToPxPriv(ALFWindowPriv *priv, int cptValue)
 {
-    return MulDiv(cptValue, priv->fonts.dpi, 7200);
+    return MulDiv(cptValue, (int)priv->fonts.dpi, 7200);
 }
 
 void
@@ -62,7 +62,7 @@ ALF_UpdateFontsPriv(HWND win, ALFWindowPriv *priv)
         // FIXME! fallback to default font, 8pt MS Shell Dlg
         ZeroMemory(&priv->fonts.lfMessageFont, sizeof(priv->fonts.lfMessageFont));
 
-        priv->fonts.lfMessageFont.lfHeight = -MulDiv(8, priv->fonts.dpi, 72);
+        priv->fonts.lfMessageFont.lfHeight = -MulDiv(8, (int)priv->fonts.dpi, 72);
         lstrcpy(priv->fonts.lfMessageFont.lfFaceName, TEXT("MS Shell Dlg"));
     }
 
@@ -246,9 +246,9 @@ ALF_DefWindowProc(HWND hwnd, UINT msg, WPARAM wparam, LPARAM lparam)
 
         if (ALF_Compat_AdjustWindowRectExForDpi(
                                &tmp,
-                               GetWindowLong(hwnd, GWL_STYLE),
+                               (DWORD)GetWindowLong(hwnd, GWL_STYLE),
                                GetMenu(hwnd) != NULL,
-                               GetWindowLong(hwnd, GWL_EXSTYLE),
+                               (DWORD)GetWindowLong(hwnd, GWL_EXSTYLE),
                                priv->fonts.dpi)) {
             MINMAXINFO *i = (MINMAXINFO *)lparam;
             i->ptMinTrackSize.x = tmp.right - tmp.left;
@@ -454,12 +454,12 @@ void
 ALF_BuildUniqueName(TCHAR *buf, const TCHAR *prefix, ULONG_PTR uniquifier)
 {
     int prefixlen = lstrlen(prefix);
-    CopyMemory(buf, prefix, prefixlen * sizeof(*prefix));
+    CopyMemory(buf, prefix, (SIZE_T)prefixlen * sizeof(*prefix));
 
     int numlen = sizeof(LONG_PTR)*2;
     int i = numlen - 1;
     while (i >= 0) {
-        buf[prefixlen + i] = "0123456789ABCDEF"[uniquifier & 0xf];
+        buf[prefixlen + i] = TEXT("0123456789ABCDEF")[uniquifier & 0xf];
         uniquifier >>= 4;
         i--;
     }
@@ -678,7 +678,7 @@ ALF_Text(HWND hwnd)
 {
     int len = GetWindowTextLength(hwnd);
     if (len > 0) {
-        TCHAR *buf = ALF_New(TCHAR, len+1);
+        TCHAR *buf = ALF_New(TCHAR, (SIZE_T)len+1);
         if (GetWindowText(hwnd, buf, len+1)) {
             return buf;
         } else {
diff --git a/alf/alf.h b/alf/alf.h
index 4ebe205..3274016 100644
--- a/alf/alf.h
+++ b/alf/alf.h
@@ -8,7 +8,7 @@ extern "C" {
 #endif
 
 typedef struct {
-    int     dpi;
+    UINT    dpi;
     LOGFONT lfMessageFont;
     HFONT   hMessageFont;
 } ALFWindowFonts;
diff --git a/alf/alfbutton.cpp b/alf/alfbutton.cpp
index 67a7236..ddf607d 100644
--- a/alf/alfbutton.cpp
+++ b/alf/alfbutton.cpp
@@ -13,8 +13,8 @@ typedef struct {
     BOOL isDefault;
     BOOL isHot;
     HTHEME hTheme;
-    UINT uxStatePrev;
-    UINT uxStateCurrent;
+    int uxStatePrev;
+    int uxStateCurrent;
     UINT itemStatePrev;
     UINT itemStateCurrent;
     DWORD uxDefaultAnimationDuration;
@@ -48,7 +48,7 @@ ALF__Button_Text_DrawStateProc(HDC hdc, LPARAM lData,  WPARAM wData, int cx, int
 }
 
 static void
-ALF__Button_RenderUxtheme(HWND hwnd, ALFButtonPriv *priv, UINT uxstate, UINT itemState, HDC hDC, LPRECT pRcItem)
+ALF__Button_RenderUxtheme(HWND hwnd, ALFButtonPriv *priv, int uxstate, UINT itemState, HDC hDC, LPRECT pRcItem)
 {
     if (ALF_Compat_IsThemeBackgroundPartiallyTransparent(priv->hTheme, BP_PUSHBUTTON, uxstate)) {
         ALF_Compat_DrawThemeParentBackground(hwnd, hDC, pRcItem);
@@ -66,7 +66,7 @@ ALF__Button_RenderUxtheme(HWND hwnd, ALFButtonPriv *priv, UINT uxstate, UINT ite
         DrawFocusRect(hDC, &content);
 
     int textlen = GetWindowTextLengthW(hwnd);
-    WCHAR *textbuf = ALF_New(WCHAR, textlen + 1);
+    WCHAR *textbuf = ALF_New(WCHAR, (SIZE_T)textlen + 1);
     GetWindowTextW(hwnd, textbuf, textlen+1);
 
     UINT style = DT_CENTER;
@@ -93,9 +93,7 @@ ALF__Button_Render95(HWND hwnd, ALFButtonPriv *priv, LPDRAWITEMSTRUCT dis)
 {
     RECT r = dis->rcItem;
 
-    int textlen = GetWindowTextLength(hwnd);
-    TCHAR *textbuf = ALF_New(TCHAR, textlen + 1);
-    GetWindowText(hwnd, textbuf, textlen+1);
+    TCHAR *textbuf = ALF_Text(hwnd);
 
     if (priv->isDefault) {
         HBRUSH framecolor = GetSysColorBrush(COLOR_WINDOWFRAME);
@@ -179,9 +177,7 @@ ALF__Button_Render3x(HWND hwnd, ALFButtonPriv *priv, LPDRAWITEMSTRUCT dis)
 
     ALF_Compat_DrawThemeParentBackground(hwnd, dis->hDC, &r);
 
-    int textlen = GetWindowTextLength(hwnd);
-    TCHAR *textbuf = ALF_New(TCHAR, textlen + 1);
-    GetWindowText(hwnd, textbuf, textlen+1);
+    TCHAR *textbuf = ALF_Text(hwnd);
 
     HBRUSH framecolor = GetSysColorBrush(COLOR_WINDOWFRAME);
     HBRUSH facecolor = GetSysColorBrush(COLOR_BTNFACE);
@@ -284,25 +280,23 @@ ALF__ButtonSubclassProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam, UINT
             oldFont = SelectFont(hdc, font);
 
         // calc drawtext style
-        DWORD style = GetWindowLong(hwnd, GWL_STYLE);
+        LONG style = GetWindowLong(hwnd, GWL_STYLE);
         UINT format = DT_LEFT | DT_EXPANDTABS | DT_CALCRECT;
         if ((style & BS_MULTILINE) == 0)
             format |= DT_SINGLELINE;
 
         RECT r = { 0, 0, 0x7FFFFFFF, 100 };
 
-        int textlen = GetWindowTextLength(hwnd);
-        TCHAR *textbuf = ALF_New(TCHAR, textlen + 1);
-        GetWindowText(hwnd, textbuf, textlen+1);
+        TCHAR *textbuf = ALF_Text(hwnd);
 
         DrawText(hdc, textbuf, -1, &r, format);
 
         ALF_Free(textbuf);
 
         int xpadding = ALF_Compat_GetSystemMetricsForDpi(SM_CXEDGE,
-            ALF_CentipointsToPixels(GetParent(hwnd), 7200)) * 2 + 6;
+            (UINT)ALF_CentipointsToPixels(GetParent(hwnd), 7200)) * 2 + 6;
         int ypadding = ALF_Compat_GetSystemMetricsForDpi(SM_CYEDGE,
-            ALF_CentipointsToPixels(GetParent(hwnd), 7200)) * 2 + 4;
+            (UINT)ALF_CentipointsToPixels(GetParent(hwnd), 7200)) * 2 + 4;
 
         SIZE *pSize = (SIZE*)(void*)lParam;
         if (pSize->cx < r.right - r.left + xpadding) {
@@ -325,7 +319,7 @@ ALF__ButtonSubclassProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam, UINT
         if (!ALF_Compat_BufferedPaintRenderAnimation(hwnd, dis->hDC)) {
             if (priv->hTheme) {
                 // Draw XP style themed button
-                UINT stateid = PBS_NORMAL;
+                int stateid = PBS_NORMAL;
 
                 if (priv->isDefault && IsChild(GetForegroundWindow(), hwnd))
                     stateid = priv->uxIsDefaultAnimating ? PBS_DEFAULTED_ANIMATING : PBS_DEFAULTED;
@@ -336,7 +330,7 @@ ALF__ButtonSubclassProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam, UINT
                 if (dis->itemState & ODS_DISABLED)
                     stateid = PBS_DISABLED;
 
-                if (priv->uxStatePrev == (UINT)-1) {
+                if (priv->uxStatePrev == -1) {
                     // initial draw
                     priv->uxStateCurrent = stateid;
                     priv->itemStateCurrent = dis->itemState;
@@ -498,8 +492,8 @@ ALF_AddButton(HWND win, WORD id, int x, int y, const TCHAR *text)
                                       NULL);
 
     ALFButtonPriv *priv = ALF_New(ALFButtonPriv, 1);
-    priv->uxStateCurrent = (UINT)-1;
-    priv->uxStatePrev = (UINT)-1;
+    priv->uxStateCurrent = -1;
+    priv->uxStatePrev = -1;
 
     ALF_Compat_SetWindowSubclass(hwndButton, ALF__ButtonSubclassProc, 0, (DWORD_PTR)priv);
 
diff --git a/alf/alfcombobox.cpp b/alf/alfcombobox.cpp
index 33a454c..6d3af5e 100644
--- a/alf/alfcombobox.cpp
+++ b/alf/alfcombobox.cpp
@@ -23,19 +23,17 @@ ALF__ComboItemHeight(HWND hwnd)
     int height = 0;
     HDC hDc = GetDC(hwnd);
     HFONT font = (HFONT)SendMessage(hwnd, WM_GETFONT, 0, 0);
-    if (font) {
-        HFONT oldfont = SelectFont(hDc, font);
+    HFONT oldfont = SelectFont(hDc, font);
 
-        TEXTMETRIC tm;
-        ZeroMemory(&tm, sizeof(tm));
+    TEXTMETRIC tm;
+    ZeroMemory(&tm, sizeof(tm));
 
-        if (GetTextMetrics(hDc, &tm)) {
-            height = tm.tmHeight;
-        }
-
-        SelectFont(hDc, oldfont);
+    if (GetTextMetrics(hDc, &tm)) {
+        height = tm.tmHeight;
     }
 
+    SelectFont(hDc, oldfont);
+
     if (!ALF_Compat_IsMinWindowsVersion(4, 0)) {
             // baseline alignment for NT3.x/Win32s
             // ideally, this would only be applied for the ODS_COMOBOXEDIT state,
@@ -84,10 +82,7 @@ ALF__ComboWindowProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
     }
     if (uMsg == WM_SETFONT && hwndChild) {
         SendMessage(hwndChild, WM_SETFONT, wParam, lParam);
-
-        int h = ALF__ComboItemHeight(hwnd);
-        if (h)
-            SendMessage(hwndChild, CB_SETITEMHEIGHT, (WPARAM)0, h);
+        SendMessage(hwndChild, CB_SETITEMHEIGHT, (WPARAM)0, (LPARAM)ALF__ComboItemHeight(hwnd));
 
         ALF_InvalidateLayout(GetParent(hwnd));
 
@@ -153,7 +148,7 @@ ALF__ComboWindowProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
 
                 if (!ps->cy) {
                     ps->cy = tm.tmHeight + 2*ALF_Compat_GetSystemMetricsForDpi(
-                            SM_CYEDGE, ALF_CentipointsToPixels(GetParent(hwnd), 7200))
+                            SM_CYEDGE, (UINT)ALF_CentipointsToPixels(GetParent(hwnd), 7200))
                         + 4 /* padding internal to the edit control */;
                 }
             }
@@ -168,9 +163,7 @@ ALF__ComboWindowProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
     if (uMsg == WM_MEASUREITEM) {
         PMEASUREITEMSTRUCT lpmis = (LPMEASUREITEMSTRUCT) lParam;
 
-        int h = ALF__ComboItemHeight(hwnd);
-        if (h)
-            lpmis->itemHeight = h;
+        lpmis->itemHeight = (UINT)ALF__ComboItemHeight(hwnd);
 
         return TRUE;
     }
@@ -208,14 +201,14 @@ ALF__ComboWindowProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
             // Get and display the text for the list item.
             int len = (int)SendMessage(lpdis->hwndItem, CB_GETLBTEXTLEN, (WPARAM)lpdis->itemID, 0);
             if (len != CB_ERR) {
-                TCHAR *buf = (TCHAR*)LocalAlloc(LPTR, (len+1) * sizeof(TCHAR));
+                TCHAR *buf = (TCHAR*)LocalAlloc(LPTR, (SIZE_T)(len+1) * sizeof(TCHAR));
 
                 SendMessage(lpdis->hwndItem, CB_GETLBTEXT,
                     lpdis->itemID, (LPARAM)buf);
 
                 ExtTextOut(lpdis->hDC, x, y,
                     ETO_CLIPPED | ETO_OPAQUE, &lpdis->rcItem,
-                    buf, lstrlen(buf), NULL);
+                    buf, (UINT)lstrlen(buf), NULL);
 
                 LocalFree(buf);
             }
@@ -238,25 +231,21 @@ ALF__ComboWindowProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
             // XXX: When resizing the combo box, it will improperly draw a selection.
             // this appears to be a well-known bug that is still not fixed, even in Win10.
             // workaround based on https://stackoverflow.com/questions/49603893/how-to-deal-with-invalidly-painted-combobox-control-in-win32-winapi
-            DWORD sel = SendMessage(hwndChild, CB_GETEDITSEL, 0, 0);
+            LRESULT sel = SendMessage(hwndChild, CB_GETEDITSEL, 0, 0);
             SendMessage(hwndChild, CB_SETEDITSEL, 0, -1);
             // SWP_NOCOPYBITS because NT 3.51 doesn't properly repaint the drop-down button
             SetWindowPos(hwndChild, NULL, 0, 0, pos->cx, 200, SWP_NOZORDER|SWP_NOACTIVATE|SWP_NOCOPYBITS);
             SendMessage(hwndChild, CB_SETEDITSEL, 0, (LPARAM)sel);
 
-            DWORD heightOffset = 0;
+            int heightOffset = 0;
             if (ALF_Compat_IsMinWindowsVersion(4, 0)) {
                 heightOffset = - 2*ALF_Compat_GetSystemMetricsForDpi(
-                            SM_CYEDGE, ALF_CentipointsToPixels(GetParent(hwnd), 7200))
+                            SM_CYEDGE, (UINT)ALF_CentipointsToPixels(GetParent(hwnd), 7200))
                             - 2;
             }
 
             SendMessage(hwndChild, CB_SETITEMHEIGHT, (WPARAM)-1, pos->cy + heightOffset);
-
-            int h = ALF__ComboItemHeight(hwnd);
-            if (h)
-                SendMessage(hwndChild, CB_SETITEMHEIGHT, (WPARAM)0, h);
-
+            SendMessage(hwndChild, CB_SETITEMHEIGHT, (WPARAM)0, (LPARAM)ALF__ComboItemHeight(hwnd));
         }
     }
 
@@ -371,7 +360,7 @@ ALF_ComboBoxStringForIndex(HWND combo, int index)
 {
     int len = (int)SendMessage(combo, ALF_CB_GETLBTEXTLEN, (WPARAM)index, 0);
     if (len > 0) {
-        TCHAR* buf = ALF_New(TCHAR, len + 1);
+        TCHAR* buf = ALF_New(TCHAR, (SIZE_T)len + 1);
         if (SendMessage(combo, ALF_CB_GETLBTEXT, (WPARAM)index, (LPARAM)buf)) {
             return buf;
         } else {
diff --git a/alf/alfcompat.cpp b/alf/alfcompat.cpp
index 5fa3be7..e3d8b15 100644
--- a/alf/alfcompat.cpp
+++ b/alf/alfcompat.cpp
@@ -21,7 +21,7 @@ DWORD ALF_DllGetVersion(const char *dll)
             hr = (*pDllGetVersion)(&dvi);
 
             if (SUCCEEDED(hr)) {
-                return MAKELONG(dvi.dwMinorVersion, dvi.dwMajorVersion);
+                return (DWORD)MAKELONG(dvi.dwMinorVersion, dvi.dwMajorVersion);
             }
         }
     }
@@ -58,7 +58,7 @@ ALF_Compat_fallbackGetDpiForWindow(HWND win)
 
     HDC hdcScreen = GetDC(NULL);
     if (hdcScreen) {
-        dpi = GetDeviceCaps(hdcScreen, LOGPIXELSY);
+        dpi = (UINT)GetDeviceCaps(hdcScreen, LOGPIXELSY);
         ReleaseDC(NULL, hdcScreen);
     }
 
diff --git a/alf/alfedit.cpp b/alf/alfedit.cpp
index afd4d08..87ddf80 100644
--- a/alf/alfedit.cpp
+++ b/alf/alfedit.cpp
@@ -24,7 +24,7 @@ ALF__EditSubclassProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam, UINT_P
 
             if (!ps->cy) {
                 ps->cy = tm.tmHeight + 2*ALF_Compat_GetSystemMetricsForDpi(
-                        SM_CYEDGE, ALF_CentipointsToPixels(GetParent(hwnd), 7200))
+                        SM_CYEDGE, (UINT)ALF_CentipointsToPixels(GetParent(hwnd), 7200))
                     + 4 /* padding internal to the edit control */;
             }
         }
diff --git a/alf/alflabel.cpp b/alf/alflabel.cpp
index b0abc4b..59c92fa 100644
--- a/alf/alflabel.cpp
+++ b/alf/alflabel.cpp
@@ -15,7 +15,7 @@ ALF__LabelTopPadding(HWND hwnd)
     // some pixels on top to align with the edit control
     // see also: alfedit.cpp
     return ALF_Compat_GetSystemMetricsForDpi(
-                SM_CYEDGE, ALF_CentipointsToPixels(GetParent(hwnd), 7200))
+                SM_CYEDGE, (UINT)ALF_CentipointsToPixels(GetParent(hwnd), 7200))
             + (!ALF_Compat_IsMinWindowsVersion(4, 0) ? 2 : 1) /* internal padding in edit control */;
 }
 
@@ -25,7 +25,7 @@ ALF__LabelLeftPadding(HWND hwnd, HDC hdc)
     // some pixels on the left to align with the edit control
     // see also: alfedit.cpp
     int p = ALF_Compat_GetSystemMetricsForDpi(
-                SM_CXEDGE, ALF_CentipointsToPixels(GetParent(hwnd), 7200));
+                SM_CXEDGE, (UINT)ALF_CentipointsToPixels(GetParent(hwnd), 7200));
 
     p += 1;
 
@@ -62,7 +62,7 @@ ALF__LabelWindowProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
         return DefWindowProc(hwnd, uMsg, wParam, lParam);
 
     if (uMsg == ALF_WM_LBL_GETSTYLE) {
-        return priv->style;
+        return (LRESULT)priv->style;
     } else if (uMsg == ALF_WM_LBL_SETSTYLE) {
         priv->style = (DWORD)lParam;
         InvalidateRect(hwnd, NULL, TRUE);
@@ -181,7 +181,7 @@ ALF__LabelWindowProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
 
             RECT r = { 0, 0, 100, 100 };
 
-            TCHAR *textbuf = ALF_New(TCHAR, textlen + 1);
+            TCHAR *textbuf = ALF_New(TCHAR, (SIZE_T)textlen + 1);
             GetWindowText(hwnd, textbuf, textlen+1);
 
             DrawText(hdcLabel, textbuf, -1, &r, format);
diff --git a/alf/alflayout.cpp b/alf/alflayout.cpp
index ce5909f..c05d355 100644
--- a/alf/alflayout.cpp
+++ b/alf/alflayout.cpp
@@ -70,9 +70,9 @@ ALF_Layout_Init(ALFLayout *layout)
     ALF_ListInit(&layout->widgets);
 
     layout->nRows = 1;
-    layout->rows = ALF_New(ALFLayoutRowOrColumn, layout->nRows);
+    layout->rows = ALF_New(ALFLayoutRowOrColumn, (SIZE_T)layout->nRows);
     layout->nColumns = 1;
-    layout->columns = ALF_New(ALFLayoutRowOrColumn, layout->nColumns);
+    layout->columns = ALF_New(ALFLayoutRowOrColumn, (SIZE_T)layout->nColumns);
 }
 
 void
@@ -107,7 +107,7 @@ ALF_Layout_EnsureRowExists(ALFLayout *layout, int rowno)
 {
     while (rowno >= layout->nRows) {
         layout->nRows *= 2;
-        layout->rows = ALF_ReNew(layout->rows, ALFLayoutRowOrColumn, layout->nRows);
+        layout->rows = ALF_ReNew(layout->rows, ALFLayoutRowOrColumn, (SIZE_T)layout->nRows);
     }
 }
 
@@ -116,7 +116,7 @@ ALF_Layout_EnsureColumnExists(ALFLayout *layout, int colno)
 {
     while (colno >= layout->nColumns) {
         layout->nColumns *= 2;
-        layout->columns = ALF_ReNew(layout->columns, ALFLayoutRowOrColumn, layout->nColumns);
+        layout->columns = ALF_ReNew(layout->columns, ALFLayoutRowOrColumn, (SIZE_T)layout->nColumns);
     }
 }
 
@@ -501,7 +501,7 @@ ALF_Layout_SetWidgetFlags(ALFLayout *layout, HWND window, HWND needle, DWORD fla
             w->flags = flags;
 
             if (flags & ALF_LAYOUT_INHERITFONT)
-                SendMessage(w->hwnd, WM_SETFONT, (LPARAM)SendMessage(window, WM_GETFONT, 0, 0), 0);
+                SendMessage(w->hwnd, WM_SETFONT, (WPARAM)SendMessage(window, WM_GETFONT, 0, 0), 0);
 
             ALF_InvalidateLayout(window);
 
@@ -747,7 +747,7 @@ ALF_Layout_HandleMessage(ALFLayout *layout, HWND hwnd, UINT msg, WPARAM wparam,
     }
 
     if (msg == ALF_WM_LYT_SETCOLFLAGS) {
-        *pRet = (LRESULT)ALF_Layout_SetColumnFlags(layout, hwnd, (int)wparam, (int)lparam);
+        *pRet = (LRESULT)ALF_Layout_SetColumnFlags(layout, hwnd, (int)wparam, (DWORD)lparam);
         return TRUE;
     }
 
@@ -777,7 +777,7 @@ ALF_Layout_HandleMessage(ALFLayout *layout, HWND hwnd, UINT msg, WPARAM wparam,
     }
 
     if (msg == ALF_WM_LYT_SETROWFLAGS) {
-        *pRet = (LRESULT)ALF_Layout_SetRowFlags(layout, hwnd, (int)wparam, (int)lparam);
+        *pRet = (LRESULT)ALF_Layout_SetRowFlags(layout, hwnd, (int)wparam, (DWORD)lparam);
         return TRUE;
     }
 
diff --git a/alf/alflayout.h b/alf/alflayout.h
index 10fa09d..ce2350f 100644
--- a/alf/alflayout.h
+++ b/alf/alflayout.h
@@ -26,7 +26,7 @@ typedef struct {
     // properties set by user
     int requestedMinWidth;
     int requestedExpandNumerator;
-    int requestedFlags;
+    DWORD requestedFlags;
 
     // calculated properties
     int calculatedMinWidth;
diff --git a/alf/alfnotebook.cpp b/alf/alfnotebook.cpp
index 8eaea6b..dc56769 100644
--- a/alf/alfnotebook.cpp
+++ b/alf/alfnotebook.cpp
@@ -357,7 +357,7 @@ ALF_NotebookTabIndex(HWND notebook, HWND tabPanel);
 HWND
 ALF_NotebookTabPanel(HWND notebook, int index)
 {
-    return (HWND)SendMessage(notebook, ALF_NB_GETPANEL, 0, (WPARAM)index);
+    return (HWND)SendMessage(notebook, ALF_NB_GETPANEL, 0, (LPARAM)index);
 }
 
 int
diff --git a/alf/alfpanel.cpp b/alf/alfpanel.cpp
index bd48721..9496e43 100644
--- a/alf/alfpanel.cpp
+++ b/alf/alfpanel.cpp
@@ -29,7 +29,7 @@ ALF_Panel_Paint(ALFPanelPriv *priv, HWND hwnd, HDC dc, RECT *r)
     if (textlen < 1)
         return;
 
-    TCHAR *textbuf = ALF_New(TCHAR, textlen + 1);
+    TCHAR *textbuf = ALF_New(TCHAR, (SIZE_T)textlen + 1);
     GetWindowText(hwnd, textbuf, textlen+1);
 
     HFONT oldFont = SelectFont(dc, priv->font);
diff --git a/makemakefile.sh b/makemakefile.sh
index 79bd0d6..e968990 100755
--- a/makemakefile.sh
+++ b/makemakefile.sh
@@ -13,8 +13,8 @@ ALF_VC6_OBJECTS=$(for i in $ALF_SOURCES; do printf ' out/%s.obj' "$(basename "$i
     printf '\n'
     printf 'CC = i686-w64-mingw32-gcc\n'
     printf 'CXX = i686-w64-mingw32-c++\n'
-    printf 'CFLAGS = -std=c99 -Wall -Wextra -mwindows -municode -DUNICODE -D_UNICODE -gstabs\n'
-    printf 'CXXFLAGS = -std=c++98 -Wall -Wextra -mwindows -municode -DUNICODE -D_UNICODE -fno-exceptions -fno-rtti -gstabs\n'
+    printf 'CFLAGS = -std=c99 -Wall -Wextra -Wconversion -mwindows -municode -DUNICODE -D_UNICODE -gstabs\n'
+    printf 'CXXFLAGS = -std=c++98 -Wall -Wextra -Wconversion -Wsign-conversion -mwindows -municode -DUNICODE -D_UNICODE -fno-exceptions -fno-rtti -gstabs\n'
     printf 'LDFLAGS = -luser32 -lcomctl32 -lshell32 -lversion -static\n'
     printf '\n'
     printf 'all: out/widgetfactory.exe out/alf/alf.c out/widgetfactory-c.exe\n'
diff --git a/widgetfactory.cpp b/widgetfactory.cpp
index dc343e6..5ef96f1 100644
--- a/widgetfactory.cpp
+++ b/widgetfactory.cpp
@@ -34,7 +34,7 @@ handleMessage(void *closure, HWND hwnd, UINT msg, WPARAM wparam, LPARAM lparam)
     (void)closure;
 
     if (msg == WM_CTLCOLORSTATIC) {
-        DWORD id = GetDlgCtrlID((HWND)lparam);
+        WORD id = (WORD)GetDlgCtrlID((HWND)lparam);
         HDC hdcStatic = (HDC)wparam;
         if (id == ID_LBLHELLO) {
             SetTextColor(hdcStatic, RGB(0,0,0));
@@ -232,7 +232,7 @@ WinMain
 void
 _entry(void)
 {
-    ExitProcess(
+    ExitProcess((UINT)
 #ifdef UNICODE
 wWinMain
 #else