Better lowering of distinct types. Noreturn function call expr recognized as a "jump" for escape analysis. Preferring "def" in libs. To upper / to lower for ascii. Initial dynlib support.

lib/std/threads/os/thread_none.c3

@@ -1,6 +1,6 @@
 module std::thread;
 
-typedef NativeMutex = distinct int;
-typedef NativeConditionVariable = distinct int;
-typedef NativeOnceFlag = distinct int;
-typedef NativeThread = distinct int;
+def NativeMutex = distinct int;
+def NativeConditionVariable = distinct int;
+def NativeOnceFlag = distinct int;
+def NativeThread = distinct int;

lib/std/threads/os/thread_posix.c3

@@ -7,30 +7,30 @@ const PTHREAD_MUTEX_NORMAL = 0;
 const PTHREAD_MUTEX_ERRORCHECK = 1;
 const PTHREAD_MUTEX_RECURSIVE = 2;
 
-typedef NativeMutex = PthreadMutex;
-typedef NativeConditionVariable = PthreadCond;
-typedef NativeThread = Pthread;
-typedef NativeOnceFlag = PthreadOnce;
+def NativeMutex = PthreadMutex;
+def NativeConditionVariable = PthreadCond;
+def NativeThread = Pthread;
+def NativeOnceFlag = PthreadOnce;
 
-typedef Pthread = distinct void*;
+def Pthread = distinct void*;
 
 $if env::OS_TYPE == LINUX:
-typedef PthreadMutex = distinct ulong[5];
-typedef PthreadAttribute = distinct ulong[7];
-typedef PthreadMutexAttribute = distinct uint;
-typedef PthreadCondAttribute = distinct uint;
-typedef PthreadCond = distinct ulong[6];
-typedef PthreadOnce = distinct uint;
+def PthreadMutex = distinct ulong[5];
+def PthreadAttribute = distinct ulong[7];
+def PthreadMutexAttribute = distinct uint;
+def PthreadCondAttribute = distinct uint;
+def PthreadCond = distinct ulong[6];
+def PthreadOnce = distinct uint;
 $else
-typedef PthreadMutex = distinct ulong[8];
-typedef PthreadMutexAttribute = distinct ulong[2];
-typedef PthreadAttribute = distinct ulong[8];
-typedef PthreadCond = distinct ulong[6];
-typedef PthreadCondAttribute = distinct ulong[8];
-typedef PthreadOnce = distinct ulong[2];
+def PthreadMutex = distinct ulong[8];
+def PthreadMutexAttribute = distinct ulong[2];
+def PthreadAttribute = distinct ulong[8];
+def PthreadCond = distinct ulong[6];
+def PthreadCondAttribute = distinct ulong[8];
+def PthreadOnce = distinct ulong[2];
 $endif
 
-typedef PosixThreadFn = fn void*(void*);
+def PosixThreadFn = fn void*(void*);
 
 extern fn int pthread_attr_destroy(PthreadAttribute*);
 extern fn int pthread_attr_getdetachstate(PthreadAttribute*, int*);

lib/std/threads/thread.c3

@@ -11,19 +11,19 @@ const ThreadModel THREAD_MODEL =  env::COMPILER_LIBC_AVAILABLE
 	? (env::os_is_win32() ? ThreadModel.WIN32 : ThreadModel.POSIX)
 	: ThreadModel.NONE;
 
-typedef MutexType = distinct int;
+def MutexType = distinct int;
 
 const MutexType MUTEX_PLAIN = 0;
 const MutexType MUTEX_TIMED = 1;
 const MutexType MUTEX_RECURSIVE = 2;
 
-typedef Mutex = distinct NativeMutex;
-typedef ConditionVariable = distinct NativeConditionVariable;
-typedef Thread = distinct NativeThread;
-typedef OnceFlag = distinct NativeOnceFlag;
-typedef OnceFn = fn void();
+def Mutex = distinct NativeMutex;
+def ConditionVariable = distinct NativeConditionVariable;
+def Thread = distinct NativeThread;
+def OnceFlag = distinct NativeOnceFlag;
+def OnceFn = fn void();
 
-typedef ThreadFn = fn int(void* arg);
+def ThreadFn = fn int(void* arg);
 
 fault ThreadFault
 {