diff --git a/uppsrc/Core/HeapImp.h b/uppsrc/Core/HeapImp.h
index f4f5ae867..15564be1b 100644
--- a/uppsrc/Core/HeapImp.h
+++ b/uppsrc/Core/HeapImp.h
@@ -1,6 +1,6 @@
 void  OutOfMemoryPanic(size_t size);
 
-void *SysAllocRaw(size_t size, int reqsize);
+void *SysAllocRaw(size_t size, size_t reqsize);
 void  SysFreeRaw(void *ptr, size_t size);
 
 void *AllocRaw4KB(int reqsize);
diff --git a/uppsrc/Core/heaputil.cpp b/uppsrc/Core/heaputil.cpp
index 974f77f04..bf5147631 100644
--- a/uppsrc/Core/heaputil.cpp
+++ b/uppsrc/Core/heaputil.cpp
@@ -18,8 +18,9 @@ void *MemoryAllocPermanentRaw(size_t size)
 		return malloc(size);
 	static byte *ptr = NULL;
 	static byte *limit = NULL;
+	ASSERT(size < INT_MAX);
 	if(ptr + size >= limit) {
-		ptr = (byte *)AllocRaw4KB(size);
+		ptr = (byte *)AllocRaw4KB((int)size);
 		limit = ptr + 4096;
 	}
 	void *p = ptr;
@@ -60,7 +61,7 @@ int sKB;
 
 int   MemoryUsedKb() { return sKB; }
 
-void *SysAllocRaw(size_t size, int reqsize)
+void *SysAllocRaw(size_t size, size_t reqsize)
 {
 	sKB += int(((size + 4095) & ~4095) >> 10);
 #ifdef PLATFORM_WIN32
@@ -75,7 +76,7 @@ void *SysAllocRaw(size_t size, int reqsize)
 		ptr = NULL;
 #endif
 	if(!ptr)
-		OutOfMemoryPanic((size_t)reqsize);
+		OutOfMemoryPanic(reqsize);
 	DoPeakProfile();
 	return ptr;
 }
diff --git a/uppsrc/Core/lheap.cpp b/uppsrc/Core/lheap.cpp
index 77ffe0c61..cdc188d4b 100644
--- a/uppsrc/Core/lheap.cpp
+++ b/uppsrc/Core/lheap.cpp
@@ -186,7 +186,7 @@ void *Heap::LAlloc(size_t& size) {
 		ptr = TryLAlloc(bini, size);
 		if(ptr) return ptr;
 	}
-	DLink *n = AddChunk(size);
+	DLink *n = AddChunk((int)size);
 	if(!n)
 		Panic("Out of memory!");
 	ptr = DivideBlock(n, (int)size, LBINS - 1);
diff --git a/uppsrc/Draw/Image.cpp b/uppsrc/Draw/Image.cpp
index 829a60428..f8f686ea9 100644
--- a/uppsrc/Draw/Image.cpp
+++ b/uppsrc/Draw/Image.cpp
@@ -250,7 +250,7 @@ void Image::Serialize(Stream& s)
 				len -= INT_MAX;
 				offset += INT_MAX;
 			}			
-			if(!s.GetAll((void*)(ptr+offset), len))
+			if(!s.GetAll((void*)(ptr+offset), (int)len))
 				s.SetError();
 			
 			b.SetDots(dots);
@@ -270,7 +270,7 @@ void Image::Serialize(Stream& s)
 			len -= INT_MAX;
 			offset += INT_MAX;
 		}
-		s.Put(ptr+offset, len);
+		s.Put(ptr+offset, (int)len);
 	}
 }
 INITBLOCK {
diff --git a/uppsrc/GridCtrl/GridDisplay.cpp b/uppsrc/GridCtrl/GridDisplay.cpp
index c1f002057..b28866d3c 100644
--- a/uppsrc/GridCtrl/GridDisplay.cpp
+++ b/uppsrc/GridCtrl/GridDisplay.cpp
@@ -292,7 +292,7 @@ int GridDisplay::GetLinesCount(int cx, const wchar* s, const Font& font, bool wr
 		{
 			if(p - e > 0 && wrap)
 			{
-				int tcx = GetTextSize(e, font, p - e).cx;
+				int tcx = GetTextSize(e, font, int(p - e)).cx;
 				if(tcx > cx)
 				{
 					lines += tcx / ccx;
@@ -365,7 +365,7 @@ void GridDisplay::DrawText(Draw &w, int mx, int x, int y, int cx, int cy, int al
 			}*/
 
 			int tx = x;
-			tsz = GetTextSize(t, font, p - t);
+			tsz = GetTextSize(t, font, int(p - t));
 
 			if(tsz.cx > gcx)
 			{
@@ -398,8 +398,8 @@ void GridDisplay::DrawText(Draw &w, int mx, int x, int y, int cx, int cy, int al
 
 			if(found)
 			{
-				int chs = t - s;
-				int che = p - s - 1;
+				int chs = int(t - s);
+				int che = int(p - s - 1);
 
 				if(fs <= che && fe >= chs)
 				{
@@ -422,12 +422,12 @@ void GridDisplay::DrawText(Draw &w, int mx, int x, int y, int cx, int cy, int al
 				if(p > t)
 				{
 					w.Clip(x, y, cx - isz.cx , cy);
-					w.DrawText(max(mx, tx), ty, t, font, tfg, p - t);
+					w.DrawText(max(mx, tx), ty, t, font, tfg, int(p - t));
 					w.End();
 				}
 			}
 			else
-				w.DrawText(max(mx, tx), ty, t, font, tfg, p - t);
+				w.DrawText(max(mx, tx), ty, t, font, tfg, int(p - t));
 
 			ty += tcy;
 			t = textbreak ? p : (p = pp + 1);