For Android, we don't actually want to build programs, but shared libraries

That's what the NativeActivity stuff wants.

For now the name of the produced shared library does not follow the
normal libfoo.so convention, but is the name of the corresponding
program on normal Unixes. To be fixed later. Or then, when
constructing an app .apk, just rename "foo" to
"libnative-foo.so".

solenv/inc/unxandr.mk

@@ -31,3 +31,20 @@ CDEFAULTOPT=-Os
 .INCLUDE : unxgcc.mk
 CDEFS+=-DARM32
 CFLAGS+=-fno-omit-frame-pointer
+
+# Override some macros set by unxgcc.mk
+
+# We don't build any "tool" style programs for non-desktop OSes like
+# Android. Just unit tests and GUI programs. (Well, that is in
+# theory. In reality any actual "app" with a GUI for Android would be
+# written and built in a totally Android-specific way, of course.)
+
+# Thus for Android we never build executable programs, just shared
+# libraries that the NativeActivity Java code will load.
+
+LINKFLAGSAPPGUI=-shared
+LINKFLAGSAPPCUI=-shared
+
+STDLIBGUIMT+=-llog -landroid
+STDLIBCUIMT+=-llog -landroid
+