Optimize stpcpy's size and speed

test/val/stpcpy.c

@@ -8,10 +8,12 @@
 #define STR_SHORT   "Hello, World!"
 #define STR_LONG    "This is a longer test string for stpcpy."
 
+char dest[512];
+char multi_page[300];
+
 int
 main ()
 {
-    char dest[50];
     const char *src_empty;
     const char *src_short;
     const char *src_long;
@@ -38,7 +40,14 @@ main ()
     assert(end == &dest[sizeof (STR_LONG) - 1]);
     printf ("Test 3 passed.\n");
 
+    memset(multi_page, 'a', sizeof(multi_page)-1);
+    multi_page[sizeof(multi_page)-1] = '\0';
+    end = stpcpy (dest, multi_page);
+    assert(!strcmp (dest, multi_page));
+    assert(!*end);
+    assert(end == &dest[sizeof (multi_page) - 1]);
+    printf ("Test 4 passed.\n");
+
     printf ("All tests passed.\n");
     return EXIT_SUCCESS;
 }
-