1.6.0: `-mode embedded` is passed as a single argv element, so releases boot in interactive mode

[ryanwinchester]

Host

Host OS: macOS 26.5.2
Host CPU: aarch64 (Apple Silicon)

zig version: 0.16.0
elixir -v: Elixir 1.20.3 (compiled with Erlang/OTP 29)
Burrito: 1.6.0 (Hex)

Target

Same as host.

---

src/erlang_launcher.zig passes -mode embedded to the emulator as a single argv element:

"-mode embedded",

erl does not split argv elements, so init never recognizes the flag and the VM boots in interactive mode. #225 fixed exactly this class of bug for "-s elixir start_cli" and "-elixir ansi_enabled true" ("passing them as single strings caused..."), and #229 documents the 1.5.0 consequence of the joined -s — but -mode was missed.

Repro (no project needed)

$ erl "-mode embedded" -noshell -eval 'io:format("~p ~p~n",[code:get_mode(), init:get_argument(mode)]),halt().'
interactive error

$ erl -mode embedded -noshell -eval 'io:format("~p ~p~n",[code:get_mode(), init:get_argument(mode)]),halt().'
embedded {ok,[["embedded"]]}

Inside a Burrito 1.6.0 binary, :init.get_argument(:mode) returns :error and code:get_mode() returns :interactive.

Consequences

Releases silently lose embedded-mode semantics:

• Modules are loaded lazily instead of preloaded at boot, so function_exported?/3 returns false for modules that haven't been called yet. We hit this as real user-visible misbehavior: a framework that gates optional callbacks on function_exported?/3 silently skipped an app's mount callback only inside the Burrito binary.
• The fail-fast guarantee of embedded mode (boot errors on missing modules) is lost.

Fix

Split the element:

"-mode",
"embedded",

Verified locally by patching deps/burrito: the flag is parsed and code:get_mode() returns :embedded.

[ryanwinchester]

PR with the fix: #236 — verified in a wrapped app (code:get_mode() now returns :embedded, flag parsed by init).