3451 archive libraries with no symbols shouldn't require a string table

@@ -103,50 +103,57 @@
                 register size_t n;
 
                 if (is64) {
                         if (sz < 8 || (sz - 8) / 8 < (n = get8(off))) {
                                 _elf_seterr(EFMT_ARSYMSZ, 0);
-                                return (0);
+                                return (NULL);
                         }
                 } else {
                         if (sz < 4 || (sz - 4) / 4 < (n = get4(off))) {
                                 _elf_seterr(EFMT_ARSYMSZ, 0);
-                                return (0);
+                                return (NULL);
                         }
                 }
                 off += eltsize;
                 endoff = off + n * eltsize;
 
                 /*
-                 * string table must be present, null terminated
+                 * If there are symbols in the symbol table, a
+                 * string table must be present and NULL terminated.
+                 *
+                 * The format dictates that the string table must always be
+                 * present, however in the case of an archive containing no
+                 * symbols GNU ar will not create one.  We are permissive for
+                 * the sake of compatibility.
                  */
-
-                if (((str = (char *)endoff) >= endstr) ||
-                    (*(endstr - 1) != '\0')) {
+                if ((n > 0) && (((str = (char *)endoff) >= endstr) ||
+                    (*(endstr - 1) != '\0'))) {
                         _elf_seterr(EFMT_ARSYM, 0);
-                        return (0);
+                        return (NULL);
                 }
 
                 /*
+                 * There is always at least one entry returned if a symtab
+                 * exists since the table's last entry is an artificial one
+                 * with a NULL as_name, but is included in the count.
+                 *
                  * overflow can occur here, but not likely
                  */
-
                 *e = n + 1;
-                n = sizeof (Elf_Arsym) * (n + 1);
-                if ((oas = malloc(n)) == 0) {
+                if ((oas = calloc(n + 1, sizeof (Elf_Arsym))) == NULL) {
                         _elf_seterr(EMEM_ARSYM, errno);
-                        return (0);
+                        return (NULL);
                 }
         }
         {
                 register Elf_Arsym      *as = (Elf_Arsym *)oas;
 
                 while (off < endoff) {
                         if (str >= endstr) {
                                 _elf_seterr(EFMT_ARSYMSTR, 0);
                                 free(oas);
-                                return (0);
+                                return (NULL);
                         }
                         if (is64)
                                 as->as_off = get8(off);
                         else
                                 as->as_off = get4(off);

@@ -156,11 +163,11 @@
                         off += eltsize;
                         while (*str++ != '\0')
                                 /* LINTED */
                                 ;
                 }
-                as->as_name = 0;
+                as->as_name = NULL;
                 as->as_off = 0;
                 as->as_hash = ~(unsigned long)0L;
         }
         return (oas);
 }