libs: Return dummy location in Location::caller

Fixes #227.

Author: RyanGlScott

libs/Patches.md

@@ -238,6 +238,12 @@ into the main commit for that patch, and then the *Update* line can be removed.
   This feature was using an `AtomicPtr<()>` with a cast from function
   pointer to `*mut ()` that we don't support in its initializer.
 
+* Return dummy location in `Location::caller` (last applied: January 22, 2026)
+
+  `crucible-mir` does not currently support the `intrinsics::caller_location()`
+  intrinsic. To prevent this function from throwing translation errors, we have
+  it return a constant dummy location.
+
 # Notes
 
 This section contains more detailed notes about why certain patches are written

libs/core/src/panic/location.rs

@@ -144,7 +144,15 @@ impl<'a> Location<'a> {
     #[track_caller]
     #[inline]
     pub const fn caller() -> &'static Location<'static> {
-        crate::intrinsics::caller_location()
+        pub const fn caller() -> &'static Location<'static> {
+            static DUMMY_LOCATION: Location<'static> = Location {
+                filename: NonNull::from_ref("dummy.rs"),
+                line: 0,
+                col: 0,
+                _filename: PhantomData,
+            };
+            &DUMMY_LOCATION
+        }
     }
 
     /// Returns the name of the source file from which the panic originated.