diff --git a/basis/io/ports/ports.factor b/basis/io/ports/ports.factor
index 3ea4c105f5..727d69adf8 100644
--- a/basis/io/ports/ports.factor
+++ b/basis/io/ports/ports.factor
@@ -27,7 +27,7 @@ TUPLE: buffered-port < port { buffer buffer } ;
 
 TUPLE: input-port < buffered-port ;
 
-M: input-port stream-element-type drop +byte+ ;
+M: input-port stream-element-type drop +byte+ ; inline
 
 : <input-port> ( handle -- input-port )
     input-port <buffered-port> ;
@@ -104,7 +104,7 @@ TUPLE: output-port < buffered-port ;
     [ nip ] [ buffer>> buffer-capacity <= ] 2bi
     [ drop ] [ stream-flush ] if ; inline
 
-M: output-port stream-element-type stream>> stream-element-type ;
+M: output-port stream-element-type stream>> stream-element-type ; inline
 
 M: output-port stream-write1
     dup check-disposed
diff --git a/core/checksums/crc32/crc32.factor b/core/checksums/crc32/crc32.factor
index 209de83763..e937cf5910 100644
--- a/core/checksums/crc32/crc32.factor
+++ b/core/checksums/crc32/crc32.factor
@@ -33,9 +33,9 @@ INSTANCE: crc32 checksum
 M: crc32 checksum-bytes
     init-crc32
     [ (crc32) ] each
-    finish-crc32 ;
+    finish-crc32 ; inline
 
 M: crc32 checksum-lines
     init-crc32
     [ [ (crc32) ] each CHAR: \n (crc32) ] each
-    finish-crc32 ;
+    finish-crc32 ; inline
diff --git a/core/io/io.factor b/core/io/io.factor
index ca36bc3b36..c134ba2108 100644
--- a/core/io/io.factor
+++ b/core/io/io.factor
@@ -99,7 +99,7 @@ SYMBOL: error-stream
     } case ; inline
 
 : stream-element-exemplar ( stream -- exemplar )
-    stream-element-type (stream-element-exemplar) ;
+    stream-element-type (stream-element-exemplar) ; inline
 
 : element-exemplar ( -- exemplar )
     input-stream get stream-element-exemplar ; inline
diff --git a/vm/code_heap.cpp b/vm/code_heap.cpp
index b7aa9185e8..9e64ff6552 100755
--- a/vm/code_heap.cpp
+++ b/vm/code_heap.cpp
@@ -5,7 +5,7 @@ namespace factor
 
 code_heap::code_heap(cell size)
 {
-	if(size > (1L << (sizeof(cell) * 8 - 6))) fatal_error("Heap too large",size);
+	if(size > ((u64)1 << (sizeof(cell) * 8 - 6))) fatal_error("Heap too large",size);
 	seg = new segment(align_page(size),true);
 	if(!seg) fatal_error("Out of memory in heap allocator",size);
 	allocator = new free_list_allocator<code_block>(size,seg->start);
diff --git a/vm/os-windows-nt.cpp b/vm/os-windows-nt.cpp
index 69df5f666f..60aad336f7 100755
--- a/vm/os-windows-nt.cpp
+++ b/vm/os-windows-nt.cpp
@@ -37,10 +37,15 @@ u64 system_micros()
 		- EPOCH_OFFSET) / 10;
 }
 
+/* On VirtualBox, QueryPerformanceCounter does not increment
+the high part every time the low part overflows.  Workaround. */
 u64 nano_count()
 {
 	LARGE_INTEGER count;
 	LARGE_INTEGER frequency;
+	static u32 hi_correction = 0;
+	static u32 hi = 0xffffffff;
+	static u32 lo = 0xffffffff;
 	BOOL ret;
 	ret = QueryPerformanceCounter(&count);
 	if(ret == 0)
@@ -49,6 +54,13 @@ u64 nano_count()
 	if(ret == 0)
 		fatal_error("QueryPerformanceFrequency", 0);
 
+	if((u32)count.LowPart < lo && (u32)count.HighPart == hi)
+		hi_correction++;
+
+	hi = count.HighPart;
+	lo = count.LowPart;
+	count.HighPart += hi_correction;
+
 	return count.QuadPart*(1000000000/frequency.QuadPart);
 }
 
diff --git a/vm/os-windows-nt.hpp b/vm/os-windows-nt.hpp
index 5b55ce1f2b..f8407aeee5 100755
--- a/vm/os-windows-nt.hpp
+++ b/vm/os-windows-nt.hpp
@@ -23,8 +23,13 @@ FACTOR_STDCALL LONG exception_handler(PEXCEPTION_POINTERS pe);
 
 // SSE traps raise these exception codes, which are defined in internal NT headers
 // but not winbase.h
+#ifndef STATUS_FLOAT_MULTIPLE_FAULTS
 #define STATUS_FLOAT_MULTIPLE_FAULTS 0xC00002B4
+#endif
+
+#ifndef STATUS_FLOAT_MULTIPLE_TRAPS
 #define STATUS_FLOAT_MULTIPLE_TRAPS  0xC00002B5
+#endif
 
 typedef HANDLE THREADHANDLE;