diff --git a/alloca.c b/alloca.c
index 7020f32c..7061cec2 100644
--- a/alloca.c
+++ b/alloca.c
@@ -209,6 +209,9 @@ alloca (size)
     register pointer new = malloc (sizeof (header) + size);
     /* Address of header.  */
 
+    if (new == 0)
+      abort();
+
     ((header *) new)->h.next = last_alloca_header;
     ((header *) new)->h.deep = depth;