From 3d2e2bd0b61e498cb8f9fc3ccc029026504dce10 Mon Sep 17 00:00:00 2001
From: Ian Butterworth <i.r.butterworth@gmail.com>
Date: Mon, 29 Jan 2024 21:51:19 -0500
Subject: [PATCH] add warning if cycle detected in extensions

---
 base/loading.jl | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/base/loading.jl b/base/loading.jl
index 5d5b6e69449240..b22e8855b282df 100644
--- a/base/loading.jl
+++ b/base/loading.jl
@@ -1392,6 +1392,10 @@ function run_extension_callbacks(pkgid::PkgId)
     extids = pop!(EXT_DORMITORY, pkgid, nothing)
     extids === nothing && return
     for extid in extids
+        if in(extid.id.name, precompilation_stack) && !isprecompiled(extid.id)
+            @warn "Dependency cycle detected in extension precompilation: $(join(precompilation_stack, " > ")) > $(extid.id.name)"
+            continue
+        end
         if extid.ntriggers > 0
             # indicate pkgid is loaded
             extid.ntriggers -= 1