Hello Robert,

i am *assuming* that, in the absence of a compelling reason, the use
of "+=" instead of "=" in this context is harmless, but unnecessary,
correct?

My understanding is that:

meta/recipes-support/libpcre/libpcre_8.43.bb:PROVIDES += "pcre"

means "I provide both "libpcre" as well as "pcre". I am assuming
that PROVIDES = "${PN}" is already set by a core BitBake rule
somewhere. (Didn't check...)

So I think it might be harmful to replace it with "=", as it would
no longer provide libpcre.