[embind] Fix signature for 64 bit types.

Long longs were incorrectly being mapped to int for the signature.

Fixes #22928

Author: brendandahl

system/include/emscripten/bind.h

@@ -607,6 +607,13 @@ struct SignatureCode<size_t> {
     }
 };
 
+template<>
+struct SignatureCode<long long> {
+    static constexpr char get() {
+        return 'j';
+    }
+};
+
 #ifdef __wasm64__
 template<>
 struct SignatureCode<long> {
@@ -629,6 +636,8 @@ template<> struct SignatureTranslator<double> { using type = double; };
 #ifdef __wasm64__
 template<> struct SignatureTranslator<long> { using type = long; };
 #endif
+template<> struct SignatureTranslator<long long> { using type = long long; };
+template<> struct SignatureTranslator<unsigned long long> { using type = long long; };
 template<> struct SignatureTranslator<size_t> { using type = size_t; };
 template<typename PtrType>
 struct SignatureTranslator<PtrType*> { using type = void*; };

test/test_other.py

@@ -3296,6 +3296,14 @@ def test_embind_return_value_policy(self):
 
     self.do_runf('embind/test_return_value_policy.cpp')
 
+  @parameterized({
+    '': [[]],
+    'asyncify': [['-sASYNCIFY=1']]
+  })
+  def test_embind_bigint(self, args):
+    self.do_runf('embind/test_bigint.cpp', '1000000000000n\n-1000000000000n',
+                 emcc_args=['-lembind', '-sWASM_BIGINT'] + args)
+
   @requires_jspi
   @parameterized({
     '': [['-sJSPI_EXPORTS=async*']],