Subject: bug#69533: 30.0.50; Wrong byte compilation of a certain apply syntax

From: Michael Heerdegen <[email-masked]>
Date: Mon, 04 Mar 2024 02:51:42 +0100

Hello,

C-h f apply says:

| ...
| With a single argument, call the argument's first element using the
| other elements as args.

Issue 1:  This doc sentence has to be moved after the following example,
because that example:

| Thus, (apply '+ 1 2 '(3 4)) returns 10.

is an example for the more widespread syntax.

That sentence actually explains a special case: it tells that this is
also allowed:

  (apply '(+ 1 2)) ==> 3

Issue 2: The byte compiler currently miscompiles such expressions:

Expected:

  (funcall (lambda () (apply '(+ 1 2)))) ==> 3

but

  (funcall (byte-compile '(lambda () (apply '(+ 1 2)))))
   ~~> Error: Invalid function: (+ 1 2)

AFAIU this is `byte-optimize-apply's fault:

(byte-optimize-apply '(apply '(+ 1 2)))
 ==> (funcall '(+ 1 2) '+ '1 '2) ; Ouch!

TIA,

Michael.