diff --git a/src/c/compiler.d b/src/c/compiler.d
index d4c68f2d8..7534228ec 100644
--- a/src/c/compiler.d
+++ b/src/c/compiler.d
@@ -3110,8 +3110,7 @@ init_compiler()
 		cl_core.compiler_dispatch =
 		cl__make_hash_table(@'eq', MAKE_FIXNUM(128), /* size */
                                     cl_core.rehash_size,
-                                    cl_core.rehash_threshold,
-				    Cnil); /* thread-safe */
+                                    cl_core.rehash_threshold);
 	int i;
 	for (i = 0; database[i].symbol; i++) {
 		ecl_sethash(database[i].symbol, dispatch_table, MAKE_FIXNUM(i));
diff --git a/src/c/main.d b/src/c/main.d
index cb6871a87..54c7c6955 100644
--- a/src/c/main.d
+++ b/src/c/main.d
@@ -585,8 +585,7 @@ cl_boot(int argc, char **argv)
 	cl_core.char_names = aux =
 	    cl__make_hash_table(@'equalp', MAKE_FIXNUM(128), /* size */
 				cl_core.rehash_size,
-                                cl_core.rehash_threshold,
-				Cnil); /* thread-safe */
+                                cl_core.rehash_threshold);
 	for (i = 0; char_names[i].elt.self; i++) {
                 cl_object name = (cl_object)(char_names + i);
 		cl_object code = MAKE_FIXNUM(i);
@@ -616,8 +615,7 @@ cl_boot(int argc, char **argv)
 	cl_core.system_properties =
 	    cl__make_hash_table(@'equal', MAKE_FIXNUM(1024), /* size */
 				cl_core.rehash_size,
-                                cl_core.rehash_threshold,
-				Ct); /* thread-safe */
+                                cl_core.rehash_threshold);
 
 	ECL_SET(@'*random-state*', ecl_make_random_state(Ct));
 
@@ -678,8 +676,7 @@ cl_boot(int argc, char **argv)
 	ECL_SET(@'si::*class-name-hash-table*',
 		cl__make_hash_table(@'eq', MAKE_FIXNUM(1024), /* size */
                                     cl_core.rehash_size,
-                                    cl_core.rehash_threshold,
-				    Ct)); /* thread safe */
+                                    cl_core.rehash_threshold));
 #endif
 
 	/*
diff --git a/src/c/package.d b/src/c/package.d
index 9c0da30aa..597aab804 100644
--- a/src/c/package.d
+++ b/src/c/package.d
@@ -113,8 +113,7 @@ make_package_hashtable()
 	return cl__make_hash_table(@'package', /* package hash table */
 				   MAKE_FIXNUM(128), /* initial size */
                                    cl_core.rehash_size,
-                                   cl_core.rehash_threshold,
-				   Cnil); /* lockable */
+                                   cl_core.rehash_threshold);
 }
 
 static cl_object
diff --git a/src/c/printer/write_object.d b/src/c/printer/write_object.d
index 0359a33e9..4ebd56a65 100644
--- a/src/c/printer/write_object.d
+++ b/src/c/printer/write_object.d
@@ -110,7 +110,7 @@ si_write_object(cl_object x, cl_object stream)
 				cl__make_hash_table(@'eq',
 						    MAKE_FIXNUM(1024),
                                                     cl_core.rehash_size,
-                                                    cl_core.rehash_threshold, Cnil);
+                                                    cl_core.rehash_threshold);
 			ecl_bds_bind(env, @'si::*circle-counter*', Ct);
 			ecl_bds_bind(env, @'si::*circle-stack*', hash);
 			si_write_object(x, cl_core.null_stream);
diff --git a/src/c/read.d b/src/c/read.d
index 6849f6b51..ff6a8264f 100644
--- a/src/c/read.d
+++ b/src/c/read.d
@@ -1172,8 +1172,7 @@ patch_sharp(cl_object x)
         cl_object table = 
                 cl__make_hash_table(@'eq', MAKE_FIXNUM(20), /* size */
                                     cl_core.rehash_size,
-                                    cl_core.rehash_threshold,
-                                    Cnil); /* thread-safe */
+                                    cl_core.rehash_threshold);
 
         pairs = ECL_SYM_VAL(the_env, @'si::*sharp-eq-context*');
         loop_for_in(pairs) {
@@ -1771,8 +1770,7 @@ ecl_readtable_set(cl_object readtable, int c, enum ecl_chattrib cat,
 		if (Null(hash)) {
 			hash = cl__make_hash_table(@'eql', MAKE_FIXNUM(128),
                                                    cl_core.rehash_size,
-                                                   cl_core.rehash_threshold,
-						   Ct);
+                                                   cl_core.rehash_threshold);
 			readtable->readtable.hash = hash;
 		}
 		_ecl_sethash(CODE_CHAR(c), hash,
@@ -1850,8 +1848,7 @@ ecl_invalid_character_p(int c)
 	cat = Null(non_terminating_p)? cat_terminating : cat_non_terminating;
 	table = cl__make_hash_table(@'eql', MAKE_FIXNUM(128),
                                     cl_core.rehash_size,
-                                    cl_core.rehash_threshold,
-				    Ct);
+                                    cl_core.rehash_threshold);
 	ecl_readtable_set(readtable, c, cat, table);
 	@(return Ct)
 @)