diff --git a/sortix/include/sortix/kernel/cpu.h b/sortix/include/sortix/kernel/cpu.h
index cd437639..87787fc6 100644
--- a/sortix/include/sortix/kernel/cpu.h
+++ b/sortix/include/sortix/kernel/cpu.h
@@ -119,8 +119,11 @@ const uint64_t URPL = 0x3;
 
 // Portable functions for loading registers.
 namespace CPU {
-extern "C" void load_registers(InterruptRegisters* regs, size_t size) SORTIX_NORETURN;
-SORTIX_NORETURN inline void LoadRegisters(InterruptRegisters* regs)
+extern "C" __attribute__((noreturn))
+void load_registers(InterruptRegisters* regs, size_t size);
+
+__attribute__((noreturn))
+inline void LoadRegisters(InterruptRegisters* regs)
 {
 	load_registers(regs, sizeof(*regs));
 }
diff --git a/sortix/include/sortix/kernel/decl.h b/sortix/include/sortix/kernel/decl.h
index 2f188857..810b8cac 100644
--- a/sortix/include/sortix/kernel/decl.h
+++ b/sortix/include/sortix/kernel/decl.h
@@ -1,6 +1,6 @@
 /*******************************************************************************
 
-    Copyright(C) Jonas 'Sortie' Termansen 2011, 2012.
+    Copyright(C) Jonas 'Sortie' Termansen 2011, 2012, 2013.
 
     This file is part of Sortix.
 
@@ -28,9 +28,6 @@
 
 typedef uintptr_t addr_t;
 
-#define SORTIX_NORETURN __attribute__((noreturn))
-#define SORTIX_MAYALIAS __attribute__((__may_alias__))
-#define SORTIX_PACKED __attribute__((packed))
 #define likely(x) __builtin_expect((x),1)
 #define unlikely(x) __builtin_expect((x),0)
 #define STATIC_ASSERT(condition) static_assert(condition, #condition)
diff --git a/sortix/include/sortix/kernel/kthread.h b/sortix/include/sortix/kernel/kthread.h
index 6c1ec769..efef6642 100644
--- a/sortix/include/sortix/kernel/kthread.h
+++ b/sortix/include/sortix/kernel/kthread.h
@@ -32,7 +32,7 @@ namespace Sortix {
 extern "C" {
 
 inline static void kthread_yield(void) { asm volatile ("int $129"); }
-void kthread_exit(void* param = NULL) SORTIX_NORETURN;
+__attribute__((noreturn)) void kthread_exit(void* param = NULL);
 typedef unsigned kthread_mutex_t;
 const kthread_mutex_t KTHREAD_MUTEX_INITIALIZER = 0;
 unsigned kthread_mutex_trylock(kthread_mutex_t* mutex);
diff --git a/sortix/include/sortix/kernel/panic.h b/sortix/include/sortix/kernel/panic.h
index 85c4eb61..4785d027 100644
--- a/sortix/include/sortix/kernel/panic.h
+++ b/sortix/include/sortix/kernel/panic.h
@@ -29,10 +29,10 @@ namespace Sortix
 {
 	// This function halts the kernel. If you wish to give an error message first,
 	// then you ought to call Panic instead.
-	extern "C" void SORTIX_NORETURN HaltKernel();
+	extern "C" __attribute__((noreturn)) void HaltKernel();
 
-	extern "C" void SORTIX_NORETURN Panic(const char* Error);
-	extern "C" void SORTIX_NORETURN PanicF(const char* Format, ...);
+	extern "C" __attribute__((noreturn)) void Panic(const char* Error);
+	extern "C" __attribute__((noreturn)) void PanicF(const char* Format, ...);
 	extern "C" void WaitForInterrupt();
 }
 
diff --git a/sortix/include/sortix/kernel/thread.h b/sortix/include/sortix/kernel/thread.h
index 1e5c3d74..324d2377 100644
--- a/sortix/include/sortix/kernel/thread.h
+++ b/sortix/include/sortix/kernel/thread.h
@@ -42,11 +42,12 @@ extern "C" void KernelInit(unsigned long magic, multiboot_info_t* bootinfo);
 typedef void (*ThreadEntry)(void* user);
 
 // Simply exits the kernel thread.
-void KernelThreadExit() SORTIX_NORETURN;
+__attribute__((noreturn)) void KernelThreadExit();
 
 // Internally used as a kernel thread entry point that exits the thread
 // upon the actual thread entry returning.
-extern "C" void BootstrapKernelThread(void* user, ThreadEntry entry) SORTIX_NORETURN;
+extern "C" __attribute__((noreturn))
+void BootstrapKernelThread(void* user, ThreadEntry entry);
 
 // These functions create a new kernel process but doesn't start it.
 Thread* CreateKernelThread(Process* process, CPU::InterruptRegisters* regs);
@@ -130,7 +131,7 @@ public:
 
 private:
 	void GotoOnSigKill(CPU::InterruptRegisters* regs);
-	void OnSigKill() SORTIX_NORETURN;
+	__attribute__((noreturn)) void OnSigKill();
 	void LastPrayer();
 	void SetHavePendingSignals();
 	void HandleSignalFixupRegsCPU(CPU::InterruptRegisters* regs);