Get parallel sweeping working on 32-bit

Author: luke-gruber

configure.ac

@@ -4298,12 +4298,9 @@ AC_ARG_ENABLE(debug-env,
 
 AC_ARG_ENABLE(parallel-sweep,
        AS_HELP_STRING([--enable-parallel-sweep],
-                      [enable background sweep thread in the default GC (requires 64-bit pthread target, [[disabled by default]])]),
+                      [enable background sweep thread in the default GC (requires pthread target, [[disabled by default]])]),
        [parallel_sweep=$enableval], [parallel_sweep=no])
 AS_IF([test "x$parallel_sweep" = xyes], [
-    AS_IF([test "$ac_cv_sizeof_voidp" -lt 8], [
-        AC_MSG_ERROR([--enable-parallel-sweep requires a 64-bit target (sizeof(void*) >= 8)])
-    ])
     AS_IF([test "x$THREAD_MODEL" != xpthread], [
         AC_MSG_ERROR([--enable-parallel-sweep requires the pthread thread model (got: $THREAD_MODEL)])
     ])