Thank you Eddy, Prefix: I reported the issue via email and the issue tracker (didn't find the signup button at first, sent an email, found the signup button) where it's filed as https://savannah.gnu.org/bugs/index.php?64746.
What Dimitry and you Eddy suggested definitely makes makes sense. Yet, I wish there was a "conditional simple expansion" operator. (https://savannah.gnu.org/bugs/index.php?64746#comment2). https://github.com/photoprism/photoprism/blob/eb44d637f3594f328131fdd0e3e987f5ca41e8bd/Makefile is the Makefile in question. (I'm not affiliated with photoprism, I'm just a user.) https://github.com/photoprism/photoprism/discussions/3790 is the discussion I had with the project. Best regards, Till Am Mo., 9. Okt. 2023 um 17:09 Uhr schrieb Edward Welbourne < edward.welbou...@qt.io>: > On Wed, Oct 4, 2023 at 6:09 PM Till Backhaus <t...@backha.us> wrote: > >> This rather short Makefile shows exponential runtime depending on the > number of variables. > >> VAR_1 ?= $(shell echo 1) > > Dmitry Goncharov (6 October 2023 17:35) replied, ending: > > Prefer simply expanded variables with $(shell). > > and if you really need the "only set if not already set" aspects of ?=, > use a suitable if check around the immediate assignments, e.g. > > ifeq($(VAR_1),) > VAR_1 := $(shell echo 1) > endif > > (and, generally, avoid using $(shell ...) for anything that can be > achieved using other make built-in functions, but I assume your real > Makefile has something more complicated as the shell command). > > Eddy. >
