Thanks for your reply. Downgrading to Elixir 1.14.5 (compiled with Erlang/OTP 25) on Erlang 26 does not make any difference: argon2_elixir therefore compiles on Erlang 25, but error-loops on Erlang 26.
mix deps.compile argon2_elixir --force
==> argon2_elixir
Microsoft (R) Program Maintenance Utility Version 14.29.30154.0
Copyright (C) Microsoft Corporation. All rights reserved.
del /Q /F priv
erl -noshell -s init stop -eval "io:setopts(standard_io, [{encoding, unicode}]), io:format(\"ERTS_INCLUDE_PATH=~ts/erts-~ts/include/\", [code:root_dir(), erlang:system_info(version)])." > Makefile.auto.win
Error! Failed to eval: io:setopts(standard_io, [{encoding, unicode}]), io:format("ERTS_INCLUDE_PATH=~ts/erts-~ts/include/", [code:root_dir(), erlang:system_info(version)]).
nmake / /F Makefile.win priv\argon2_nif.dll
Microsoft (R) Program Maintenance Utility Version 14.29.30154.0
Copyright (C) Microsoft Corporation. All rights reserved.
BREAK: (a)bort (A)bort with dump (c)ontinue (p)roc info (i)nfo
(l)oaded (v)ersion (k)ill (D)b-tables (d)istribution
Terminate batch job (Y/N)?
The syntax of the command is incorrect.