On Fri, Feb 03, 2023 at 11:28:03AM +0100, Geert Uytterhoeven wrote:

On Fri, Feb 3, 2023 at 11:17 AM Tudor Ambarus [off-list ref] wrote:

quoted

The deciding factor for when a/an should be used is the sound
that begins the word which follows these indefinite articles,
rather than the letter which does. Use "an SPI" (SPI begins
with the consonant letter S, but the S is pronounced with its
letter name, "es.").

While I agree with your pronunciation, I believe the SPI maintainer
(which you forgot to CC) pronounces it in James Bond-style, i.e. rhymes
with "spy" ;-)

Yes, I do.  To the best of my knowledge most people just say "spy"
rather than pronouncing the letters or anything.

In any case as I said in reply to one of the individual patches English
isn't regular enough to go with hard and fast rules on anything, and the
letter rule is much more commonly used where something is needed.  Using
an here looks wrong to me, and the fact that a is so widely used does
suggest that usage has escaped whatever rule there is.