Merge pull request #231 from GaloisInc/T227-caller-dummy-location

`libs`: Return dummy location in `Location::caller`

Author: RyanGlScott

libs/Patches.md

@@ -255,6 +255,12 @@ into the main commit for that patch, and then the *Update* line can be removed.
   slightly such that we build a `&mut [u8]` slice and then cast it to a `*mut
   u8`, thereby avoiding the need for `u32` altogether.
 
+* 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 +144,13 @@ impl<'a> Location<'a> {
     #[track_caller]
     #[inline]
     pub const fn caller() -> &'static Location<'static> {
-        crate::intrinsics::caller_location()
+        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.