diff --git a/src/fallback.rs b/src/fallback.rs
index fbce9c4..3b1441b 100644
--- a/src/fallback.rs
+++ b/src/fallback.rs
@@ -664,6 +664,13 @@ impl Span {
     }
 }
 
+#[cfg(all(not(wrap_proc_macro), feature = "proc-macro"))]
+impl From<proc_macro::Span> for crate::Span {
+    fn from(_: proc_macro::Span) -> Self {
+        crate::Span::_new(Span::call_site())
+    }
+}
+
 impl Debug for Span {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
         #[cfg(span_locations)]