ipxe/src/include/stdarg.h

#ifndef _STDARG_H
#define _STDARG_H

typedef __builtin_va_list va_list;
#define va_start( ap, last ) __builtin_va_start ( ap, last )
#define va_arg( ap, type ) __builtin_va_arg ( ap, type )
#define va_end( ap ) __builtin_va_end ( ap )
#define va_copy( dest, src ) __builtin_va_copy ( dest, src )

#endif /* _STDARG_H */