Don't throw during auto-precompilation

src/API.jl

@@ -1574,9 +1574,15 @@ function precompile(ctx::Context, pkgs::Vector{PackageSpec}; internal_call::Bool
             pluralde = n_direct_errs == 1 ? "y" : "ies"
             direct = strict ? "" : "direct "
             err_msg = "The following $n_direct_errs $(direct)dependenc$(pluralde) failed to precompile:\n$(err_str[1:end-1])"
-            if internal_call && isinteractive() && !get(ENV, "CI", false)
-                println(io, "  To see a full report use `", color_string("julia>", :green), " err`")
-                setglobal!(Base.MainInclude, :err, PkgError(err_msg))
+            if internal_call # aka. auto-precompilation
+                if isinteractive() && !get(ENV, "CI", false)
+                    println(io, "  To see a full report use `", color_string("julia>", :green), " err`")
+                    setglobal!(Base.MainInclude, :err, PkgError(err_msg))
+                else
+                    # auto-precompilation shouldn't throw but if the user can't easily access the
+                    # error messages, just show them
+                    print(io, err_msg)
+                end
             else
                 println(io, "")
                 pkgerror(err_msg)