Configure: Fix compilation error on some systems

[khwilliamson]

See #22793

This typo in a printf format causes some C compilations to fail; others to just warn. However stderr is redirected to /dev/null, so we weren't aware of this issue.

When it fails, other issues cause perl to not be usable on the system.

This commit should be added to maint 5.40 and 5.38

• This set of changes requires a perldelta entry, to be furnished

[jkeenan]

See #22793

This typo in a printf format causes some C compilations to fail; others to just warn. However stderr is redirected to /dev/null, so we weren't aware of this issue.

Do you recall which platforms this was a problem on?

[tonycoz]

Do you recall which platforms this was a problem on?

Any system that has the compiler enable -Werror=format by default, though I don't know any that do that. Ubuntu was setting -Werror=format-security but that's different.

In any case it fixes a bug (one that produces undefined behaviour technically).

[jkeenan]

This commit should be added to maint 5.40 and 5.38

If so, then before doing those 2 maintenance releases, we should line up some machines on which we can test this patch. (Passes against blead for me.)

[khwilliamson]

The OP has tested on their machine running 5.38; and I have tested it on my machine running 5.38