# define freea free
#endif
-/* Maybe we should also define a variant
- nmalloca (size_t n, size_t s) - behaves like malloca (n * s)
- If this would be useful in your application. please speak up. */
+/* nmalloca(N,S) is an overflow-safe variant of malloca (N * S).
+ It allocates an array of N objects, each with S bytes of memory,
+ on the stack. S must be positive and N must be nonnegative.
+ The array must be freed using freea() before the function returns. */
+#if 1
+/* Cf. the definition of xalloc_oversized. */
+# define nmalloca(n, s) \
+ ((n) > (size_t) (sizeof (ptrdiff_t) <= sizeof (size_t) ? -1 : -2) / (s) \
+ ? NULL \
+ : malloca ((n) * (s)))
+#else
+extern void * nmalloca (size_t n, size_t s);
+#endif
#ifdef __cplusplus