verilator/docs/guide/deprecations.rst

.. SPDX-FileCopyrightText: 2003-2026 Wilson Snyder
.. SPDX-License-Identifier: LGPL-3.0-only OR Artistic-2.0

Deprecations
============

The following deprecated items are scheduled for future removal:

C++14 compiler support
   Verilator currently requires a C++20 or newer compiler for timing, and a
   C++14 or newer compiler for both compiling Verilator and compiling
   Verilated models with --no-timing.

   Verilator will require C++20 or newer compilers for both compiling
   Verilator and compiling all Verilated models no sooner than May 2025.
   (Although this date has expired, this change is currently on hold until
   the Ubuntu LTS versions of GCC and clang use C++20 by default, estimated
   May 2028.)

`--structs-packed` option
   The :vlopt:`--structs-packed` option was introduced when Verilator was
   first implementing unpacked structs. That feature has been stable now
   for multiple years, so :vlopt:`--structs-packed` should no longer be
   used. Thus :vlopt:`--structs-packed` will change to a no-operation flag
   and the related :option:`UNPACKED` warning will never be issued no
   sooner than September 2026.

tcmalloc support
   Verilator currently supports the default malloc, tcmalloc, or jemalloc.
   As jemalloc has better performance, support for tcmalloc may be removed
   no sooner than January 2027.