diff -urN autotrace-0.31.1.old/xstd.h autotrace-0.31.1/xstd.h

--- autotrace-0.31.1.old/xstd.h	2002-10-11 02:14:17.000000000 +0530

+++ autotrace-0.31.1/xstd.h	2021-04-30 15:22:25.853589944 +0530

@@ -20,6 +20,7 @@

 #define XMALLOC(new_mem, size)			\

 do						\

   {						\

+    assert(size);                              \

     new_mem = (at_address) malloc (size);	\

     assert(new_mem);				\

   } while (0)

@@ -28,6 +29,7 @@

 #define XCALLOC(new_mem, size)			\

 do						\

   {						\

+    assert(size);                              \

     new_mem = (at_address) calloc (size, 1);	\

     assert(new_mem);				\

   } while (0)

@@ -55,6 +57,7 @@

 #define XMALLOC(new_mem, size)					\

 do								\

   {								\

+    assert(size);                                              \

     (at_address&)(new_mem) = (at_address) malloc (size);	\

      assert(new_mem);						\

   } while (0) 

@@ -63,6 +66,7 @@

 #define XCALLOC(new_mem, sizex)					\

 do								\

   {								\

+    assert(size);                                              \

     (at_address&)(new_mem) = (void *) calloc (sizex, 1);	\

     assert(new_mem);						\

   } while (0)