Fix bug in spawn and document todo

Author: phischu

libraries/common/io.effekt

@@ -16,7 +16,7 @@ extern async def spawn(task: Task[Unit]): Unit =
   js "$effekt.capture(k => { setTimeout(() => k($effekt.unit), 0); return $effekt.run(${task}) })"
   llvm """
     call void @c_yield(%Stack %stack)
-    call void @run(%Pos %task)
+    call void @run(%Pos ${task})
     ret void
   """
 

libraries/common/io/network.effekt

@@ -53,12 +53,14 @@ namespace internal {
       ret void
     """
 
+  /// The buffer must be kept alive by using it after the call
   extern async def read(handle: Int, buffer: ByteArray, offset: Int, size: Int): Int =
     llvm """
       call void @c_tcp_read(%Int ${handle}, %Pos ${buffer}, %Int ${offset}, %Int ${size}, %Stack %stack)
       ret void
     """
 
+  /// The buffer must be kept alive by using it after the call
   extern async def write(handle: Int, buffer: ByteArray, offset: Int, size: Int): Int =
     llvm """
       call void @c_tcp_write(%Int ${handle}, %Pos ${buffer}, %Int ${offset}, %Int ${size}, %Stack %stack)

libraries/llvm/io.c

@@ -263,6 +263,7 @@ void c_tcp_read(Int handle, struct Pos buffer, Int offset, Int size, Stack stack
 
     char* buffer_ptr = (char*)(c_bytearray_data(buffer) + offset);
     erasePositive(buffer);
+    // TODO panic if this was the last reference
 
     tcp_read_closure_t* read_closure = malloc(sizeof(tcp_read_closure_t));
     read_closure->stack = stack;
@@ -290,6 +291,7 @@ void c_tcp_write(Int handle, struct Pos buffer, Int offset, Int size, Stack stac
 
     uv_buf_t buf = uv_buf_init((char*)(c_bytearray_data(buffer) + offset), size);
     erasePositive(buffer);
+    // TODO panic if this was the last reference
 
     uv_write_t* request = malloc(sizeof(uv_write_t));
     request->data = stack;