From 21d05c0f56fa3070ee242fd27702530028a90586 Mon Sep 17 00:00:00 2001
From: Michael Abbott <32575566+mcabbott@users.noreply.github.com>
Date: Sat, 23 Nov 2024 17:39:25 -0500
Subject: [PATCH] add explicit errors for 2nd order

---
 src/gradient.jl | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/src/gradient.jl b/src/gradient.jl
index d970251510..57b08416a0 100644
--- a/src/gradient.jl
+++ b/src/gradient.jl
@@ -35,6 +35,12 @@ function gradient(f, args...; zero::Bool=true)
     for a in args
         _ensure_noenzyme(a)
     end
+    if Zygote.isderiving()
+        error("""`Flux.gradient` does not support use within a Zygote gradient.
+            If what you are doing worked on Flux < 0.14, then calling `Zygote.gradiet` directly should still work.
+            If you are writing new code, then Zygote over Zygote is heavily discouraged.
+            """)
+    end
     Zygote.gradient(f, args...)
 end
 
@@ -167,6 +173,12 @@ function withgradient(f, args...; zero::Bool=true)
     for a in args
         _ensure_noenzyme(a)
     end
+    if Zygote.isderiving()
+        error("""`Flux.withgradient` does not support use within a Zygote gradient.
+            If what you are doing worked on Flux < 0.14, then calling `Zygote.gradiet` directly should still work.
+            If you are writing new code, then Zygote over Zygote is heavily discouraged.
+            """)
+    end
     Zygote.withgradient(f, args...)
 end