diff --git a/compiler/res/prog8lib/diskio.p8 b/compiler/res/prog8lib/diskio.p8
index 2bbbf49a2..612897b0c 100644
--- a/compiler/res/prog8lib/diskio.p8
+++ b/compiler/res/prog8lib/diskio.p8
@@ -438,7 +438,9 @@ io_error:
     ; If you don't give an address_override, the location in memory is taken from the 2-byte file header.
     ; If you specify a custom address_override, the first 2 bytes in the file are ignored
     ; and the rest is loaded at the given location in memory.
-    ; Returns the number of bytes loaded.
+    ; Returns the number of bytes loaded if address_override was given, otherwise the end address.
+    ;  TODO this is stupid - why not always return the number of bytes loaded and let the caller figure out the rest
+    ;
     ; NOTE: when the load is larger than 64Kb and/or spans multiple RAM banks
     ;       (which is possible on the Commander X16), the returned size is not correct,
     ;       because it doesn't take the number of ram banks into account.
diff --git a/docs/source/todo.rst b/docs/source/todo.rst
index af5956e9b..a8593ed95 100644
--- a/docs/source/todo.rst
+++ b/docs/source/todo.rst
@@ -3,6 +3,21 @@ TODO
 
 For next compiler release (7.6)
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+fix compiler crash when trying to concatenate string var and string literal.
+
+fix return value of diskio.load() (see commment) and possibly other routines?
+
+optimization in call convention:
+non-asm subroutines with just a single byte or word parameter:
+    pass the parameter via A or A/Y registers.
+    add code to set the parameter variable in the start of the subroutine itself,
+    rather than requiring the caller to set it there. This is not faster but saves a lot of bytes of code.
+
+rewrite multiple choice if into when:
+    if X==1 or X==2 or X==3 { truepart } else { falsepart }
+    ->  when X  { 1,2,3->truepart   else->falsepart }
+    same with assignment if the lhs is simple var or memaddr
+
 ...