diff --git a/cranelift/codegen/src/machinst/buffer.rs b/cranelift/codegen/src/machinst/buffer.rs
index 6a5c06c04e4d..03debd945468 100644
--- a/cranelift/codegen/src/machinst/buffer.rs
+++ b/cranelift/codegen/src/machinst/buffer.rs
@@ -680,10 +680,14 @@ impl<I: VCodeInst> MachBuffer<I> {
         //    (end of buffer)
         self.data.truncate(b.start as usize);
         self.fixup_records.truncate(b.fixup);
-        while let Some(last_srcloc) = self.srclocs.last() {
+        while let Some(mut last_srcloc) = self.srclocs.last_mut() {
             if last_srcloc.end <= b.start {
                 break;
             }
+            if last_srcloc.start < b.start {
+                last_srcloc.end = b.start;
+                break;
+            }
             self.srclocs.pop();
         }
         // State: