Custom Query (1030 matches)

Compiling a file containing:

(defun outer-fun ()
  (defun inner-fun () nil)
  (inner-fun))

gives a warning (undefined function inner-fun) when compiled with (optimize (safety 3)) but not otherwise.

encountered while trying to get test suite to compile cleanly:

? (let ((x 17)) (defvar *foo* x))
;Compiler warnings :
;   In an anonymous lambda form: Undeclared free variable *FOO*

Very occasionally, one sees something like (from memory) :

Error: wrong number of args to FOO:
       2 arguments provided, 2 accepted

(however exactly that's presented/worded.)

A working theory is that that's icache-related and that the comparison of nargs with a constant and the conditional UUO that follows are in different cache lines and some instruction other than the comparison is actually executed instead. (That's a working theory only because this error was a symptom of failure to flush the icache on an iOS system.)

If it happens again, we should try to determine the address of the code vector and see if it's plausible that the first and second instructions are in different cache lines.

(The lisp kernel -may- try to determine the cache line size from information in the ELF aux vector or via sysctl or something like that; I'm not sure if it does, and it's unlikely that the value is used.)