diff --git a/src/tools/rust-analyzer/crates/proc-macro-srv/src/server_impl/rust_analyzer_span.rs b/src/tools/rust-analyzer/crates/proc-macro-srv/src/server_impl/rust_analyzer_span.rs
index 552d99f51ba..bfc3ea5d03a 100644
--- a/src/tools/rust-analyzer/crates/proc-macro-srv/src/server_impl/rust_analyzer_span.rs
+++ b/src/tools/rust-analyzer/crates/proc-macro-srv/src/server_impl/rust_analyzer_span.rs
@@ -142,7 +142,13 @@ impl server::TokenStream for RaSpanServer {
         stream.is_empty()
     }
     fn from_str(&mut self, src: &str) -> Self::TokenStream {
-        Self::TokenStream::from_str(src, self.call_site).expect("cannot parse string")
+        Self::TokenStream::from_str(src, self.call_site).unwrap_or_else(|e| {
+            Self::TokenStream::from_str(
+                &format!("compile_error!(\"failed to parse str to token stream: {e}\")"),
+                self.call_site,
+            )
+            .unwrap()
+        })
     }
     fn to_string(&mut self, stream: &Self::TokenStream) -> String {
         stream.to_string()
diff --git a/src/tools/rust-analyzer/crates/proc-macro-srv/src/server_impl/token_id.rs b/src/tools/rust-analyzer/crates/proc-macro-srv/src/server_impl/token_id.rs
index 7720c6d83c3..e478b1c853b 100644
--- a/src/tools/rust-analyzer/crates/proc-macro-srv/src/server_impl/token_id.rs
+++ b/src/tools/rust-analyzer/crates/proc-macro-srv/src/server_impl/token_id.rs
@@ -131,7 +131,13 @@ impl server::TokenStream for TokenIdServer {
         stream.is_empty()
     }
     fn from_str(&mut self, src: &str) -> Self::TokenStream {
-        Self::TokenStream::from_str(src, self.call_site).expect("cannot parse string")
+        Self::TokenStream::from_str(src, self.call_site).unwrap_or_else(|e| {
+            Self::TokenStream::from_str(
+                &format!("compile_error!(\"failed to parse str to token stream: {e}\")"),
+                self.call_site,
+            )
+            .unwrap()
+        })
     }
     fn to_string(&mut self, stream: &Self::TokenStream) -> String {
         stream.to_string()
diff --git a/src/tools/rust-analyzer/crates/proc-macro-srv/src/server_impl/token_stream.rs b/src/tools/rust-analyzer/crates/proc-macro-srv/src/server_impl/token_stream.rs
index 4d8d496418b..dbcb5a3143a 100644
--- a/src/tools/rust-analyzer/crates/proc-macro-srv/src/server_impl/token_stream.rs
+++ b/src/tools/rust-analyzer/crates/proc-macro-srv/src/server_impl/token_stream.rs
@@ -131,7 +131,7 @@ pub(super) mod token_stream {
                 call_site,
                 src,
             )
-            .ok_or("lexing error")?;
+            .ok_or_else(|| format!("lexing error: {src}"))?;
 
             Ok(TokenStream::with_subtree(subtree))
         }