(strdupa): New macro.

diff --git a/string/string.h b/string/string.h
index 0f99531..95dcba0 100644 (file)
--- a/string/string.h
+++ b/string/string.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 1991, 1992, 1993, 1995 Free Software Foundation, Inc.
+/* Copyright (C) 1991, 92, 93, 95, 96 Free Software Foundation, Inc.
 This file is part of the GNU C Library.
 
 The GNU C Library is free software; you can redistribute it and/or
@@ -91,6 +91,16 @@ extern size_t strxfrm __P ((char *__dest, __const char *__src, size_t __n));
 extern char *strdup __P ((__const char *__s));
 #endif
 
+#if defined (__USE_GNU) && defined (__GNUC__)
+/* Duplicate S, returning an identical alloca'd string.  */
+#define strdupa(s)                                                           \
+({                                                                           \
+    const char *__old = (s);                                                 \
+    size_t __len = strlen (__old) + 1;                                       \
+    memcpy (__builtin_alloca (__len), __old, __len);                         \
+})
+#endif
+
 /* Find the first occurrence of C in S.  */
 extern char *strchr __P ((__const char *__s, int __c));
 /* Find the last occurrence of C in S.  */