C, add __int64 as a fundamental type

tests/roots/test-domain-c/index.rst

@@ -6,6 +6,12 @@ directives
 
 .. c:function:: int hello(char *name)
 
+   :rtype: int
+
+.. c:function:: MyStruct hello2(char *name)
+
+   :rtype: MyStruct
+
 .. c:member:: float Sphinx.version
 .. c:var:: int version
 

tests/test_domain_c.py

@@ -108,6 +108,8 @@ def test_expressions():
     exprCheck('int *restrict*')
     exprCheck('int *(*)(double)')
     exprCheck('const int*')
+    exprCheck('__int64')
+    exprCheck('unsigned __int64')
 
     # actual expressions
 
@@ -260,6 +262,8 @@ def test_member_definitions():
     check('member', 'double a', {1: 'a'})
 
     check('member', 'unsigned long a', {1: 'a'})
+    check('member', '__int64 a', {1: 'a'})
+    check('member', 'unsigned __int64 a', {1: 'a'})
 
     check('member', 'int .a', {1: 'a'})