From a11ea95bc3f2eb81af4840c3a6a283a854c0447e Mon Sep 17 00:00:00 2001
From: "Cliff L. Biffle" <cliff@oxide.computer>
Date: Wed, 3 Apr 2024 11:14:32 -0700
Subject: [PATCH] userlib: fail if no-panic and panic-messages are both set

---
 sys/userlib/src/lib.rs | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/sys/userlib/src/lib.rs b/sys/userlib/src/lib.rs
index 3abd3abff..c537e3001 100644
--- a/sys/userlib/src/lib.rs
+++ b/sys/userlib/src/lib.rs
@@ -1288,6 +1288,15 @@ pub unsafe extern "C" fn _start() -> ! {
     }
 }
 
+// Make the no-panic and panic-messages features mutually exclusive.
+#[cfg(all(feature = "no-panic", feature = "panic-messages"))]
+compile_error!(
+    "Both the userlib/panic-messages and userlib/no-panic feature flags \
+     are set! This doesn't make a lot of sense and is probably not what \
+     you wanted. (If you have a use case for this combination, update \
+     this check in userlib.)"
+);
+
 /// Panic handler for user tasks with the `panic-messages` feature enabled. This
 /// handler will try its best to generate a panic message, up to a maximum
 /// buffer size (configured below).