From a9de8c0deef5b79ad92391805b8869a04ece63df Mon Sep 17 00:00:00 2001
From: Ori Ziv <oriz@starkware.co>
Date: Tue, 31 Mar 2026 18:10:42 +0300
Subject: [PATCH] fix: return None for macro rule with missing param kind
 instead of panicking

Fixes #9797
---
 .../src/expr/test_data/statements             | 32 +++++++++++++++++++
 .../src/items/macro_declaration.rs            |  5 +--
 2 files changed, 33 insertions(+), 4 deletions(-)

diff --git a/crates/cairo-lang-semantic/src/expr/test_data/statements b/crates/cairo-lang-semantic/src/expr/test_data/statements
index a17045609d3..2f067833691 100644
--- a/crates/cairo-lang-semantic/src/expr/test_data/statements
+++ b/crates/cairo-lang-semantic/src/expr/test_data/statements
@@ -216,3 +216,35 @@ fn unstable_function_with_note() -> felt252 {
 //! > function_body
 
 //! > expected_diagnostics
+
+//! > ==========================================================================
+
+//! > Declarative macro with parameter missing kind specifier.
+
+//! > test_runner_name
+test_function_diagnostics(expect_diagnostics: true)
+
+//! > function_code
+fn foo() {
+    m!(1);
+}
+
+//! > function_name
+foo
+
+//! > module_code
+macro m {
+    ($x) => { 0 };
+}
+
+//! > expected_diagnostics
+error[E1010]: Macro parameter must have a kind.
+ --> lib.cairo:2:7
+    ($x) => { 0 };
+      ^
+
+error[E2158]: No matching rule found in inline macro `m`.
+ --> lib.cairo:5:5
+    m!(1);
+    ^^^^^
+
diff --git a/crates/cairo-lang-semantic/src/items/macro_declaration.rs b/crates/cairo-lang-semantic/src/items/macro_declaration.rs
index 02ceceb8f15..9cdfee16155 100644
--- a/crates/cairo-lang-semantic/src/items/macro_declaration.rs
+++ b/crates/cairo-lang-semantic/src/items/macro_declaration.rs
@@ -295,10 +295,7 @@ fn is_macro_rule_match_ex<'db>(
                     if let ast::OptionParamKind::ParamKind(param_kind) = param.kind(db) {
                         param_kind.kind(db).into()
                     } else {
-                        unreachable!(
-                            "Missing macro rule param kind, should have been handled by the \
-                             parser."
-                        )
+                        return None;
                     };
                 let placeholder_name = param.name(db).as_syntax_node().get_text_without_trivia(db);
                 match placeholder_kind {