Index: uspace/lib/c/include/stdarg.h
===================================================================
--- uspace/lib/c/include/stdarg.h	(revision a7a7f8c35340d0b14e5d74cb7398920fde63e13e)
+++ uspace/lib/c/include/stdarg.h	(revision 6efb4d2ae69379d91c4fccc34083faf72518fd07)
@@ -43,4 +43,5 @@
 #define va_arg(ap, type)    __builtin_va_arg(ap, type)
 #define va_end(ap)          __builtin_va_end(ap)
+#define va_copy(dst, src)   __builtin_va_copy(dst, src)
 
 #endif