diff --git a/dlls/advapi32/advapi.c b/dlls/advapi32/advapi.c
index 5496205e78e..f4dea242bca 100644
--- a/dlls/advapi32/advapi.c
+++ b/dlls/advapi32/advapi.c
@@ -23,9 +23,10 @@
 
 #include <errno.h>
 #include <stdio.h>
-#include <unistd.h>
 #include <string.h>
-#include <pwd.h>
+#ifdef HAVE_PWD_H
+# include <pwd.h>
+#endif
 
 #include "winbase.h"
 #include "windef.h"
@@ -48,15 +49,17 @@ GetUserNameA( LPSTR lpszName, LPDWORD lpSize )
   size_t len;
   char *name;
 
+#ifdef HAVE_GETPWUID
   struct passwd *pwd = getpwuid( getuid() );
-  if (!pwd)
-  {
+  name = pwd ? pwd->pw_name : NULL;
+#else
+  name = getenv("USER");
+#endif
+  if (!name) {
     ERR("Username lookup failed: %s\n", strerror(errno));
     return 0;
   }
 
-  name = pwd->pw_name;
-
   /* We need to include the null character when determining the size of the buffer. */
   len = strlen(name) + 1;
   if (len > *lpSize)
diff --git a/dlls/advapi32/registry.c b/dlls/advapi32/registry.c
index 3efb3ce1665..725d02bbb37 100644
--- a/dlls/advapi32/registry.c
+++ b/dlls/advapi32/registry.c
@@ -28,7 +28,6 @@
 
 #include <stdlib.h>
 #include <stdio.h>
-#include <unistd.h>
 
 #include "winbase.h"
 #include "winreg.h"
diff --git a/library/debug.c b/library/debug.c
index 42926d053d7..ab80b014dbd 100644
--- a/library/debug.c
+++ b/library/debug.c
@@ -25,7 +25,6 @@
 #include <stdio.h>
 #include <stdarg.h>
 #include <string.h>
-#include <unistd.h>
 #include <ctype.h>
 
 #include "wine/debug.h"
diff --git a/library/loader.c b/library/loader.c
index 556295256a8..54e01fba831 100644
--- a/library/loader.c
+++ b/library/loader.c
@@ -26,7 +26,6 @@
 #include <stdlib.h>
 #include <string.h>
 #include <sys/types.h>
-#include <unistd.h>
 #ifdef HAVE_SYS_MMAN_H
 #include <sys/mman.h>
 #endif
diff --git a/library/port.c b/library/port.c
index 01effca3dde..78e51a93560 100644
--- a/library/port.c
+++ b/library/port.c
@@ -31,7 +31,10 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
-#include <unistd.h>
+#include <time.h>
+#ifdef HAVE_UNISTD_H
+# include <unistd.h>
+#endif
 #include <sys/types.h>
 #ifdef HAVE_SYS_INTTYPES_H
 # include <sys/inttypes.h>
@@ -101,7 +104,7 @@ void *memmove( void *dest, const void *src, unsigned int len )
         memcpy( dst, src, len );
     }
     /* Otherwise do it the hard way (FIXME: could do better than this) */
-    else if (dst < src)
+    else if (dst < (char *)src)
     {
         while (len--) *dst++ = *((char *)src)++;
     }
@@ -668,6 +671,8 @@ char *gcvt (double number, size_t  ndigit,  char *buff)
  */
 #ifdef __i386__
 
+#ifdef __GNUC__
+
 __ASM_GLOBAL_FUNC(interlocked_cmpxchg,
                   "movl 12(%esp),%eax\n\t"
                   "movl 8(%esp),%ecx\n\t"
@@ -696,6 +701,54 @@ __ASM_GLOBAL_FUNC(interlocked_xchg_add,
                   "lock; xaddl %eax,(%edx)\n\t"
                   "ret");
 
+#elif defined(_MSC_VER)
+
+__declspec(naked) long interlocked_cmpxchg( long *dest, long xchg, long compare )
+{
+    __asm mov eax, 12[esp];
+    __asm mov ecx, 8[esp];
+    __asm mov edx, 4[esp];
+    __asm lock cmpxchg [edx], ecx;
+    __asm ret;
+}
+
+__declspec(naked) void *interlocked_cmpxchg_ptr( void **dest, void *xchg, void *compare )
+{
+    __asm mov eax, 12[esp];
+    __asm mov ecx, 8[esp];
+    __asm mov edx, 4[esp];
+    __asm lock cmpxchg [edx], ecx;
+    __asm ret;
+}
+
+__declspec(naked) long interlocked_xchg( long *dest, long val )
+{
+    __asm mov eax, 8[esp];
+    __asm mov edx, 4[esp];
+    __asm lock xchg [edx], eax;
+    __asm ret;
+}
+
+__declspec(naked) void *interlocked_xchg_ptr( void **dest, void *val )
+{
+    __asm mov eax, 8[esp];
+    __asm mov edx, 4[esp];
+    __asm lock xchg [edx], eax;
+    __asm ret;
+}
+
+__declspec(naked) long interlocked_xchg_add( long *dest, long incr )
+{
+    __asm mov eax, 8[esp];
+    __asm mov edx, 4[esp];
+    __asm lock xadd [edx], eax;
+    __asm ret;
+}
+
+#else
+# error You must implement the interlocked* functions for your compiler
+#endif
+
 #elif defined(__powerpc__)
 void* interlocked_cmpxchg_ptr( void **dest, void* xchg, void* compare)
 {
diff --git a/memory/instr.c b/memory/instr.c
index bbea64aba1f..f1a30d24fbb 100644
--- a/memory/instr.c
+++ b/memory/instr.c
@@ -44,7 +44,7 @@ inline static void *make_ptr( CONTEXT86 *context, DWORD seg, DWORD off, int long
     if (ISV86(context)) return PTR_REAL_TO_LIN( seg, off );
     if (IS_SELECTOR_SYSTEM(seg)) return (void *)off;
     if (!long_addr) off = LOWORD(off);
-    return MapSL( MAKESEGPTR( seg, 0 ) ) + off;
+    return (char *) MapSL( MAKESEGPTR( seg, 0 ) ) + off;
 }
 
 inline static void *get_stack( CONTEXT86 *context )
@@ -54,7 +54,7 @@ inline static void *get_stack( CONTEXT86 *context )
     if (IS_SELECTOR_SYSTEM(context->SegSs))
         return (void *)context->Esp;
     if (IS_SELECTOR_32BIT(context->SegSs))
-        return MapSL( MAKESEGPTR( context->SegSs, 0 ) ) + context->Esp;
+        return (char *) MapSL( MAKESEGPTR( context->SegSs, 0 ) ) + context->Esp;
     return MapSL( MAKESEGPTR( context->SegSs, LOWORD(context->Esp) ) );
 }
 
@@ -249,7 +249,7 @@ static BYTE *INSTR_GetOperandAddr( CONTEXT86 *context, BYTE *instr,
     if (IS_SELECTOR_SYSTEM(seg)) return (BYTE *)(base + (index << ss));
     if (((seg & 7) != 7) || IS_SELECTOR_FREE(seg)) return NULL;
     if (wine_ldt_copy.limit[seg >> 3] < (base + (index << ss))) return NULL;
-    return MapSL( MAKESEGPTR( seg, 0 ) ) + base + (index << ss);
+    return (char *) MapSL( MAKESEGPTR( seg, 0 ) ) + base + (index << ss);
 #undef GET_VAL
 }