diff --git a/lib/libc/file.c b/lib/libc/file.c
index 6cfc4d7..614fc20 100644
--- a/lib/libc/file.c
+++ b/lib/libc/file.c
@@ -47,6 +47,8 @@ _alloc_file()
     }
 
     // XXX: malloc
+
+    return NULL;
 }
 
 void
diff --git a/sbin/sysctl/sysctl.c b/sbin/sysctl/sysctl.c
index 2ab4bc7..818d233 100644
--- a/sbin/sysctl/sysctl.c
+++ b/sbin/sysctl/sysctl.c
@@ -59,7 +59,7 @@ main(int argc, const char *argv[])
 		break;
 	    case SYSCTL_TYPE_INT:
 		OSSysCtl(SYSCTLTable[i].path, &scInt, NULL);
-		printf("%s: %ld\n", SYSCTLTable[i].path, scInt.value);
+		printf("%s: %lld\n", SYSCTLTable[i].path, scInt.value);
 		break;
 	    case SYSCTL_TYPE_BOOL:
 		OSSysCtl(SYSCTLTable[i].path, &scBool, NULL);
diff --git a/sys/amd64/mp.c b/sys/amd64/mp.c
index a60cdae..d0ef06c 100644
--- a/sys/amd64/mp.c
+++ b/sys/amd64/mp.c
@@ -170,14 +170,14 @@ MP_CrossCall(CrossCallCB cb, void *arg)
     volatile CrossCallFrame frame;
 
     // Setup frame
-    memset(&frame, 0, sizeof(frame));
+    memset((void *)&frame, 0, sizeof(frame));
     frame.cb = cb;
     frame.arg = arg;
     frame.count = 1;
 
     Critical_Enter();
 
-    cpus[CPU()].frame = &frame;
+    cpus[CPU()].frame = (CrossCallFrame *)&frame;
     cpuid(0, 0, 0, 0, 0);
 
     if (LAPIC_Broadcast(T_CROSSCALL) < 0)
diff --git a/sys/kern/semaphore.c b/sys/kern/semaphore.c
index ff2c5dd..0acd2f0 100644
--- a/sys/kern/semaphore.c
+++ b/sys/kern/semaphore.c
@@ -12,7 +12,7 @@
 #include <sys/semaphore.h>
 #include <sys/thread.h>
 
-Spinlock semaListLock = { 0, 0, 0, 0, 0, 0, "Semaphore List" };
+Spinlock semaListLock = { 0, 0, 0, 0, 0, 0, 0, 0, "Semaphore List" };
 LIST_HEAD(SemaListHead, Semaphore) semaList = LIST_HEAD_INITIALIZER(semaList);
 
 extern uint64_t ticksPerSecond;
diff --git a/tests/lwiptest.c b/tests/lwiptest.c
index f880902..51dc874 100644
--- a/tests/lwiptest.c
+++ b/tests/lwiptest.c
@@ -1,4 +1,6 @@
 
+#include <unistd.h>
+
 #include <lwip/init.h>
 #include <lwip/ip.h>
 #include <lwip/sockets.h>