diff --git a/c_headers/stdarg.h b/c_headers/stdarg.h
index f6635105e07d3301d4eae12a904bbc6348f95bf8..d603d353f5fafddfa016bcedfb0f2f786b95123a 100644
--- a/c_headers/stdarg.h
+++ b/c_headers/stdarg.h
@@ -26,10 +26,14 @@
 #ifndef __STDARG_H
 #define __STDARG_H
 
+/* zig: added because macos _va_list.h was duplicately defining va_list
+ */
 #ifndef _VA_LIST
+#ifndef _VA_LIST_T
 typedef __builtin_va_list va_list;
 #define _VA_LIST
 #endif
+#endif
 #define va_start(ap, param) __builtin_va_start(ap, param)
 #define va_end(ap)          __builtin_va_end(ap)
 #define va_arg(ap, type)    __builtin_va_arg(ap, type)