guard HAVE_LONG_LONG definition to prevent redefinition (#28898)
diff --git a/Include/pyport.h b/Include/pyport.h
index 20f3db7..28bf4b2 100644
--- a/Include/pyport.h
+++ b/Include/pyport.h
@@ -37,9 +37,10 @@
* integral synonyms. Only define the ones we actually need.
*/
-// long long is required now. Define HAVE_LONG_LONG unconditionally for
-// compatibility.
+// long long is required. Ensure HAVE_LONG_LONG is defined for compatibility.
+#ifndef HAVE_LONG_LONG
#define HAVE_LONG_LONG
+#endif
#ifndef PY_LONG_LONG
#define PY_LONG_LONG long long
/* If LLONG_MAX is defined in limits.h, use that. */