`cfunction` ABI adapters not pre-compiled for CodeInstances from an existing sys/pkgimage

[topolarity]

The logic here:

julia/src/aotcompile.cpp

Lines 607 to 608 in 45f5834

	auto it = compiled_mi.find(mi);
	if (it != compiled_mi.end()) {

expects to be able to find the target code for the cfunc ABI adapter in the current worklist. However, it's also possible for code to be available, e.g., in an external sys/pkgimage, in which case it won't end up in the worklist.

As a result, the ABI adapter does not end up pre-compiled.

This happens when pre-compiling REPL, where it uses Base.Timer functionality (

julia/base/asyncevent.jl

Line 133 in d88369d

this, @cfunction(uv_timercb, Cvoid, (Ptr{Cvoid},)),

). We are unable to pre-compile the ABI adapter for Base.uv_timercb.

We should still be able to AOT-compile this adapter by "linking" to the external CodeInstance via a gvar, similar to what we already do when invoking external CodeInstances.