fix JuliaLang#46918, unstable jl_binding_type behavior (JuliaLang#4…

…6994)

Now it will return `nothing` before the binding has been resolved,
and afterward fully look up the binding as declared by the owner.

src/module.c

@@ -394,12 +394,11 @@ JL_DLLEXPORT jl_value_t *jl_binding_owner(jl_module_t *m, jl_sym_t *var)
 JL_DLLEXPORT jl_value_t *jl_binding_type(jl_module_t *m, jl_sym_t *var)
 {
  JL_LOCK(&m->lock);
- jl_binding_t *b = (jl_binding_t*)ptrhash_get(&m->bindings, var);
- if (b == HT_NOTFOUND || b->owner == NULL)
- b = using_resolve_binding(m, var, NULL, 0);
+ jl_binding_t *b = _jl_get_module_binding(m, var);
  JL_UNLOCK(&m->lock);
- if (b == NULL)
+ if (b == HT_NOTFOUND || b->owner == NULL)
  return jl_nothing;
+ b = jl_get_binding(m, var);
  jl_value_t *ty = jl_atomic_load_relaxed(&b->ty);
  return ty ? ty : jl_nothing;
 }

test/core.jl

@@ -7845,3 +7845,24 @@ module SpecializeModuleTest
  @specialize
 end
 @test methods(SpecializeModuleTest.f)[1].nospecialize & 0b11 == 0b10
+
+let # https://github.com/JuliaLang/julia/issues/46918
+ # jl_binding_type shouldn't be unstable
+ code = quote
+ res1 = ccall(:jl_binding_type, Any, (Any, Any), Main, :stderr)
+
+ stderr
+
+ res2 = ccall(:jl_binding_type, Any, (Any, Any), Main, :stderr)
+
+ res3 = ccall(:jl_binding_type, Any, (Any, Any), Main, :stderr)
+
+ print(stdout, res1, " ", res2, " ", res3)
+ end |> x->join(x.args, ';')
+ cmd = `$(Base.julia_cmd()) -e $code` # N.B make sure not to pass this code as `:block`
+ stdout = IOBuffer()
+ stderr = IOBuffer()
+ @test success(pipeline(Cmd(cmd); stdout, stderr))
+ @test isempty(String(take!(stderr))) # make sure no error has happened
+ @test String(take!(stdout)) == "nothing IO IO"
+end