include: Add vadefs.h header.

include/Makefile.in

@@ -527,6 +527,7 @@ SOURCES = \
 	msvcrt/time.h \
 	msvcrt/uchar.h \
 	msvcrt/unistd.h \
+	msvcrt/vadefs.h \
 	msvcrt/wchar.h \
 	msvcrt/wctype.h \
 	mswsock.h \

include/msvcrt/vadefs.h

+/*
+ * Variable argument definitions
+ *
+ * Copyright 2022 Jacek Caban
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
+ */
+
+#ifndef _INC_VADEFS
+#define _INC_VADEFS
+
+#ifdef __cplusplus
+#define _ADDRESSOF(v) (&reinterpret_cast<const char &>(v))
+#else
+#define _ADDRESSOF(v) (&(v))
+#endif
+
+#if defined(__GNUC__) || defined(__clang__)
+
+typedef __builtin_va_list va_list;
+#define _crt_va_start(v,l)  __builtin_va_start(v,l)
+#define _crt_va_arg(v,l)    __builtin_va_arg(v,l)
+#define _crt_va_end(v)      __builtin_va_end(v)
+#define _crt_va_copy(d,s)   __builtin_va_copy(d,s)
+
+#else
+
+typedef char *va_list;
+
+#if defined(__i386__)
+#define _INTSIZEOF(n) ((sizeof(n) + sizeof(int) - 1) & ~(sizeof(int) - 1))
+#define _crt_va_start(v,l)  ((v) = (va_list)_ADDRESSOF(l) + _INTSIZEOF(l))
+#define _crt_va_arg(v,l)    (*(l *)(((v) += _INTSIZEOF(l)) - _INTSIZEOF(l)))
+#define _crt_va_end(v)      ((v) = (va_list)0)
+#define _crt_va_copy(d,s)   ((d) = (s))
+#endif
+
+#endif
+
+#endif /* _INC_VADEFS */