Compilation.lowering_jni_main_decls is populated by lowerToIR (iterating
foreign_class_map for is_main && !is_foreign && runtime==jni_class,
deduped by foreign_path); each entry carries the pre-rendered Java source
from jni_java_emit.emitJavaSource.
createApk extended: when the emission list is non-empty, write each
.java under <stage>/java/<pkg>/<Class>.java, javac --release 11 to
<stage>/classes/, d8 --release --lib <android_jar> --output <stage>
to produce <stage>/classes.dex, then zip the .dex into the unaligned
APK at root level. javac discovery: $JAVA_HOME/bin/javac first, then
`which javac`.
Manifest still hardcodes android.app.NativeActivity (slice 3 wires the
user's class name + android:hasCode="true"), so the bundled .dex is
present but unreferenced at runtime. End-to-end verified via dexdump on
the smoke example's APK — Lco/swipelab/sxjnimain/SxApp; extending
NativeActivity shows up in classes.dex. Non-#jni_main APK builds
(99-android-egl-clear.sx) produce the same shape as before.
Cross-compile tuple added for examples/ffi-jni-main-01-emit.sx
(compile-only — APK exercise is manual).