diff --git a/gcc/adjust-alignment.cc b/gcc/adjust-alignment.cc
index 2db41e8b4c8..5c5f8f4e5c0 100644
--- a/gcc/adjust-alignment.cc
+++ b/gcc/adjust-alignment.cc
@@ -50,7 +50,7 @@ public:
     : gimple_opt_pass (pass_data_adjust_alignment, ctxt)
   {}
 
-  virtual unsigned int execute (function *);
+  unsigned int execute (function *) final override;
 }; // class pass_adjust_alignment
 
 } // anon namespace
diff --git a/gcc/asan.cc b/gcc/asan.cc
index 4b583e54efd..5df333555ea 100644
--- a/gcc/asan.cc
+++ b/gcc/asan.cc
@@ -4209,9 +4209,15 @@ public:
   {}
 
   /* opt_pass methods: */
-  opt_pass * clone () { return new pass_asan (m_ctxt); }
-  virtual bool gate (function *) { return gate_asan () || gate_hwasan (); }
-  virtual unsigned int execute (function *) { return asan_instrument (); }
+  opt_pass * clone () final override { return new pass_asan (m_ctxt); }
+  bool gate (function *) final override
+  {
+    return gate_asan () || gate_hwasan ();
+  }
+  unsigned int execute (function *) final override
+  {
+    return asan_instrument ();
+  }
 
 }; // class pass_asan
 
@@ -4246,11 +4252,14 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *)
+  bool gate (function *) final override
     {
       return !optimize && (gate_asan () || gate_hwasan ());
     }
-  virtual unsigned int execute (function *) { return asan_instrument (); }
+  unsigned int execute (function *) final override
+  {
+    return asan_instrument ();
+  }
 
 }; // class pass_asan_O0
 
diff --git a/gcc/auto-inc-dec.cc b/gcc/auto-inc-dec.cc
index 85fe9d14950..481e7af6895 100644
--- a/gcc/auto-inc-dec.cc
+++ b/gcc/auto-inc-dec.cc
@@ -1692,7 +1692,7 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *)
+  bool gate (function *) final override
     {
       if (!AUTO_INC_DEC)
 	return false;
@@ -1701,7 +1701,7 @@ public:
     }
 
 
-  unsigned int execute (function *);
+  unsigned int execute (function *) final override;
 
 }; // class pass_inc_dec
 
diff --git a/gcc/auto-profile.cc b/gcc/auto-profile.cc
index 2b34b80b82d..6533722817f 100644
--- a/gcc/auto-profile.cc
+++ b/gcc/auto-profile.cc
@@ -1752,13 +1752,13 @@ public:
   }
 
   /* opt_pass methods: */
-  virtual bool
-  gate (function *)
+  bool
+  gate (function *) final override
   {
     return flag_auto_profile;
   }
-  virtual unsigned int
-  execute (function *)
+  unsigned int
+  execute (function *) final override
   {
     return autofdo::auto_profile ();
   }
diff --git a/gcc/bb-reorder.cc b/gcc/bb-reorder.cc
index d20ccb83aa6..bdbe2e9ea7a 100644
--- a/gcc/bb-reorder.cc
+++ b/gcc/bb-reorder.cc
@@ -2633,7 +2633,7 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *)
+  bool gate (function *) final override
     {
       if (targetm.cannot_modify_jumps_p ())
 	return false;
@@ -2641,7 +2641,7 @@ public:
 	      && (flag_reorder_blocks || flag_reorder_blocks_and_partition));
     }
 
-  virtual unsigned int execute (function *);
+  unsigned int execute (function *) final override;
 
 }; // class pass_reorder_blocks
 
@@ -2794,8 +2794,8 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *);
-  virtual unsigned int execute (function *);
+  bool gate (function *) final override;
+  unsigned int execute (function *) final override;
 
 }; // class pass_duplicate_computed_gotos
 
@@ -2937,8 +2937,8 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *);
-  virtual unsigned int execute (function *);
+  bool gate (function *) final override;
+  unsigned int execute (function *) final override;
 
 }; // class pass_partition_blocks
 
diff --git a/gcc/cfgcleanup.cc b/gcc/cfgcleanup.cc
index 335af4911bb..18047da7b24 100644
--- a/gcc/cfgcleanup.cc
+++ b/gcc/cfgcleanup.cc
@@ -3227,7 +3227,7 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual unsigned int execute (function *);
+  unsigned int execute (function *) final override;
 
 }; // class pass_jump
 
@@ -3274,11 +3274,11 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *)
+  bool gate (function *) final override
   {
     return flag_thread_jumps && flag_expensive_optimizations;
   }
-  virtual unsigned int execute (function *);
+  unsigned int execute (function *) final override;
 
 }; // class pass_jump_after_combine
 
@@ -3322,7 +3322,7 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual unsigned int execute (function *)
+  unsigned int execute (function *) final override
     {
       cleanup_cfg (flag_crossjumping ? CLEANUP_CROSSJUMP : 0);
       return 0;
diff --git a/gcc/cfgexpand.cc b/gcc/cfgexpand.cc
index bb33c1b939e..1d7f6b260d0 100644
--- a/gcc/cfgexpand.cc
+++ b/gcc/cfgexpand.cc
@@ -6573,7 +6573,7 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual unsigned int execute (function *);
+  unsigned int execute (function *) final override;
 
 }; // class pass_expand
 
diff --git a/gcc/cfgrtl.cc b/gcc/cfgrtl.cc
index 06be46d75df..9a4651f61a3 100644
--- a/gcc/cfgrtl.cc
+++ b/gcc/cfgrtl.cc
@@ -483,7 +483,7 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual unsigned int execute (function *);
+  unsigned int execute (function *) final override;
 
 }; // class pass_free_cfg
 
@@ -3698,7 +3698,7 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual unsigned int execute (function *)
+  unsigned int execute (function *) final override
     {
       cfg_layout_initialize (0);
       return 0;
@@ -3737,7 +3737,7 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual unsigned int execute (function *);
+  unsigned int execute (function *) final override;
 
 }; // class pass_outof_cfg_layout_mode
 
diff --git a/gcc/cgraphbuild.cc b/gcc/cgraphbuild.cc
index fdd17aa5a2d..bae44591a29 100644
--- a/gcc/cgraphbuild.cc
+++ b/gcc/cgraphbuild.cc
@@ -290,7 +290,7 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual unsigned int execute (function *);
+  unsigned int execute (function *) final override;
 
 }; // class pass_build_cgraph_edges
 
@@ -484,8 +484,11 @@ public:
   {}
 
   /* opt_pass methods: */
-  opt_pass * clone () { return new pass_rebuild_cgraph_edges (m_ctxt); }
-  virtual unsigned int execute (function *)
+  opt_pass * clone () final override
+  {
+    return new pass_rebuild_cgraph_edges (m_ctxt);
+  }
+  unsigned int execute (function *) final override
   {
     return cgraph_edge::rebuild_edges ();
   }
@@ -524,10 +527,10 @@ public:
   {}
 
   /* opt_pass methods: */
-  opt_pass * clone () {
+  opt_pass * clone () final override {
     return new pass_remove_cgraph_callee_edges (m_ctxt);
   }
-  virtual unsigned int execute (function *);
+  unsigned int execute (function *) final override;
 
 }; // class pass_remove_cgraph_callee_edges
 
diff --git a/gcc/combine-stack-adj.cc b/gcc/combine-stack-adj.cc
index e8ba2717063..e76d60a8f7e 100644
--- a/gcc/combine-stack-adj.cc
+++ b/gcc/combine-stack-adj.cc
@@ -823,8 +823,8 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *);
-  virtual unsigned int execute (function *)
+  bool gate (function *) final override;
+  unsigned int execute (function *) final override
     {
       return rest_of_handle_stack_adjustments ();
     }
diff --git a/gcc/combine.cc b/gcc/combine.cc
index 9a34ef847aa..a8305273e44 100644
--- a/gcc/combine.cc
+++ b/gcc/combine.cc
@@ -15015,8 +15015,8 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *) { return (optimize > 0); }
-  virtual unsigned int execute (function *)
+  bool gate (function *) final override { return (optimize > 0); }
+  unsigned int execute (function *) final override
     {
       return rest_of_handle_combine ();
     }
diff --git a/gcc/compare-elim.cc b/gcc/compare-elim.cc
index 985c0c92182..e869d9d3249 100644
--- a/gcc/compare-elim.cc
+++ b/gcc/compare-elim.cc
@@ -954,7 +954,7 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *)
+  bool gate (function *) final override
     {
       /* Setting this target hook value is how a backend indicates the need.  */
       if (targetm.flags_regnum == INVALID_REGNUM)
@@ -962,7 +962,7 @@ public:
       return flag_compare_elim_after_reload;
     }
 
-  virtual unsigned int execute (function *)
+  unsigned int execute (function *) final override
     {
       return execute_compare_elim_after_reload ();
     }
diff --git a/gcc/config/i386/i386-features.cc b/gcc/config/i386/i386-features.cc
index 6fe41c3c24f..24e8336689c 100644
--- a/gcc/config/i386/i386-features.cc
+++ b/gcc/config/i386/i386-features.cc
@@ -1873,13 +1873,13 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *)
+  bool gate (function *) final override
     {
       return TARGET_AVX && TARGET_VZEROUPPER
 	&& flag_expensive_optimizations && !optimize_size;
     }
 
-  virtual unsigned int execute (function *)
+  unsigned int execute (function *) final override
     {
       return rest_of_handle_insert_vzeroupper ();
     }
@@ -1908,23 +1908,23 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *)
+  bool gate (function *) final override
     {
       return ((!timode_p || TARGET_64BIT)
 	      && TARGET_STV && TARGET_SSE2 && optimize > 1);
     }
 
-  virtual unsigned int execute (function *)
+  unsigned int execute (function *) final override
     {
       return convert_scalars_to_vector (timode_p);
     }
 
-  opt_pass *clone ()
+  opt_pass *clone () final override
     {
       return new pass_stv (m_ctxt);
     }
 
-  void set_pass_param (unsigned int n, bool param)
+  void set_pass_param (unsigned int n, bool param) final override
     {
       gcc_assert (n == 0);
       timode_p = param;
@@ -2135,14 +2135,14 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *)
+  bool gate (function *) final override
     {
       need_endbr = (flag_cf_protection & CF_BRANCH) != 0;
       patchable_area_size = crtl->patch_area_size - crtl->patch_area_entry;
       return need_endbr || patchable_area_size;
     }
 
-  virtual unsigned int execute (function *)
+  unsigned int execute (function *) final override
     {
       timevar_push (TV_MACH_DEP);
       rest_of_insert_endbr_and_patchable_area (need_endbr,
@@ -2399,7 +2399,7 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *)
+  bool gate (function *) final override
     {
       return (TARGET_AVX
 	      && TARGET_SSE_PARTIAL_REG_DEPENDENCY
@@ -2408,7 +2408,7 @@ public:
 	      && optimize_function_for_speed_p (cfun));
     }
 
-  virtual unsigned int execute (function *)
+  unsigned int execute (function *) final override
     {
       return remove_partial_avx_dependency ();
     }
diff --git a/gcc/coroutine-passes.cc b/gcc/coroutine-passes.cc
index 7b9a97af5a2..21ac9469805 100644
--- a/gcc/coroutine-passes.cc
+++ b/gcc/coroutine-passes.cc
@@ -213,9 +213,9 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *) { return flag_coroutines; };
+  bool gate (function *) final override { return flag_coroutines; };
 
-  virtual unsigned int execute (function *f ATTRIBUTE_UNUSED)
+  unsigned int execute (function *f ATTRIBUTE_UNUSED) final override
   {
     return execute_lower_coro_builtins ();
   }
@@ -511,12 +511,12 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *f)
+  bool gate (function *f) final override
     {
       return flag_coroutines && f->coroutine_component;
     }
 
-  virtual unsigned int execute (function *f ATTRIBUTE_UNUSED)
+  unsigned int execute (function *f ATTRIBUTE_UNUSED) final override
   {
     return execute_early_expand_coro_ifns ();
   }
diff --git a/gcc/cprop.cc b/gcc/cprop.cc
index cf01c2d79a9..580f811545d 100644
--- a/gcc/cprop.cc
+++ b/gcc/cprop.cc
@@ -1953,15 +1953,18 @@ public:
   {}
 
   /* opt_pass methods: */
-  opt_pass * clone () { return new pass_rtl_cprop (m_ctxt); }
-  virtual bool gate (function *fun)
+  opt_pass * clone () final override { return new pass_rtl_cprop (m_ctxt); }
+  bool gate (function *fun) final override
     {
       return optimize > 0 && flag_gcse
 	&& !fun->calls_setjmp
 	&& dbg_cnt (cprop);
     }
 
-  virtual unsigned int execute (function *) { return execute_rtl_cprop (); }
+  unsigned int execute (function *) final override
+  {
+    return execute_rtl_cprop ();
+  }
 
 }; // class pass_rtl_cprop
 
diff --git a/gcc/cse.cc b/gcc/cse.cc
index a18b599d324..b13afd4ba72 100644
--- a/gcc/cse.cc
+++ b/gcc/cse.cc
@@ -7571,8 +7571,11 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *) { return optimize > 0; }
-  virtual unsigned int execute (function *) { return rest_of_handle_cse (); }
+  bool gate (function *) final override { return optimize > 0; }
+  unsigned int execute (function *) final override
+  {
+    return rest_of_handle_cse ();
+  }
 
 }; // class pass_cse
 
@@ -7642,12 +7645,15 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *)
+  bool gate (function *) final override
     {
       return optimize > 0 && flag_rerun_cse_after_loop;
     }
 
-  virtual unsigned int execute (function *) { return rest_of_handle_cse2 (); }
+  unsigned int execute (function *) final override
+  {
+    return rest_of_handle_cse2 ();
+  }
 
 }; // class pass_cse2
 
@@ -7715,12 +7721,12 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *)
+  bool gate (function *) final override
     {
       return optimize > 0 && flag_rerun_cse_after_global_opts;
     }
 
-  virtual unsigned int execute (function *)
+  unsigned int execute (function *) final override
     {
       return rest_of_handle_cse_after_global_opts ();
     }
diff --git a/gcc/dce.cc b/gcc/dce.cc
index 6676cbcd429..64aa0aa471d 100644
--- a/gcc/dce.cc
+++ b/gcc/dce.cc
@@ -849,12 +849,12 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *)
+  bool gate (function *) final override
     {
       return optimize > 1 && flag_dce && dbg_cnt (dce_ud);
     }
 
-  virtual unsigned int execute (function *)
+  unsigned int execute (function *) final override
     {
       return rest_of_handle_ud_dce ();
     }
@@ -1280,12 +1280,12 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *)
+  bool gate (function *) final override
     {
       return optimize > 0 && flag_dce && dbg_cnt (dce_fast);
     }
 
-  virtual unsigned int execute (function *)
+  unsigned int execute (function *) final override
     {
       return rest_of_handle_fast_dce ();
     }
diff --git a/gcc/df-core.cc b/gcc/df-core.cc
index a901b84878f..97b2bbf6d2b 100644
--- a/gcc/df-core.cc
+++ b/gcc/df-core.cc
@@ -741,8 +741,8 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *) { return optimize > 0; }
-  virtual unsigned int execute (function *)
+  bool gate (function *) final override { return optimize > 0; }
+  unsigned int execute (function *) final override
     {
       return rest_of_handle_df_initialize ();
     }
@@ -781,8 +781,8 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *) { return optimize == 0; }
-  virtual unsigned int execute (function *)
+  bool gate (function *) final override { return optimize == 0; }
+  unsigned int execute (function *) final override
     {
       return rest_of_handle_df_initialize ();
     }
@@ -848,7 +848,7 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual unsigned int execute (function *)
+  unsigned int execute (function *) final override
     {
       return rest_of_handle_df_finish ();
     }
diff --git a/gcc/dse.cc b/gcc/dse.cc
index 30c11cee034..83c572f6220 100644
--- a/gcc/dse.cc
+++ b/gcc/dse.cc
@@ -3747,12 +3747,15 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *)
+  bool gate (function *) final override
     {
       return optimize > 0 && flag_dse && dbg_cnt (dse1);
     }
 
-  virtual unsigned int execute (function *) { return rest_of_handle_dse (); }
+  unsigned int execute (function *) final override
+  {
+    return rest_of_handle_dse ();
+  }
 
 }; // class pass_rtl_dse1
 
@@ -3787,12 +3790,15 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *)
+  bool gate (function *) final override
     {
       return optimize > 0 && flag_dse && dbg_cnt (dse2);
     }
 
-  virtual unsigned int execute (function *) { return rest_of_handle_dse (); }
+  unsigned int execute (function *) final override
+  {
+    return rest_of_handle_dse ();
+  }
 
 }; // class pass_rtl_dse2
 
diff --git a/gcc/dwarf2cfi.cc b/gcc/dwarf2cfi.cc
index ab7c5cc5b27..bef3165e691 100644
--- a/gcc/dwarf2cfi.cc
+++ b/gcc/dwarf2cfi.cc
@@ -3788,8 +3788,11 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *);
-  virtual unsigned int execute (function *) { return execute_dwarf2_frame (); }
+  bool gate (function *) final override;
+  unsigned int execute (function *) final override
+  {
+    return execute_dwarf2_frame ();
+  }
 
 }; // class pass_dwarf2_frame
 
diff --git a/gcc/early-remat.cc b/gcc/early-remat.cc
index 2738892b4e7..5c368293c35 100644
--- a/gcc/early-remat.cc
+++ b/gcc/early-remat.cc
@@ -2615,12 +2615,12 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *)
+  bool gate (function *) final override
   {
     return optimize > 1 && NUM_POLY_INT_COEFFS > 1;
   }
 
-  virtual unsigned int execute (function *f)
+  unsigned int execute (function *f) final override
   {
     auto_sbitmap selected_modes (NUM_MACHINE_MODES);
     bitmap_clear (selected_modes);
diff --git a/gcc/except.cc b/gcc/except.cc
index b94de425557..7d7ce40c846 100644
--- a/gcc/except.cc
+++ b/gcc/except.cc
@@ -2047,7 +2047,7 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual unsigned int execute (function *)
+  unsigned int execute (function *) final override
     {
       return set_nothrow_function_flags ();
     }
@@ -2722,8 +2722,8 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *);
-  virtual unsigned int execute (function *)
+  bool gate (function *) final override;
+  unsigned int execute (function *) final override
     {
       int ret = convert_to_eh_region_ranges ();
       maybe_add_nop_after_section_switch ();
diff --git a/gcc/final.cc b/gcc/final.cc
index a9868861bd2..81e21cb8db6 100644
--- a/gcc/final.cc
+++ b/gcc/final.cc
@@ -808,7 +808,10 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual unsigned int execute (function *) { return compute_alignments (); }
+  unsigned int execute (function *) final override
+  {
+    return compute_alignments ();
+  }
 
 }; // class pass_compute_alignments
 
@@ -4360,7 +4363,10 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual unsigned int execute (function *) { return rest_of_handle_final (); }
+  unsigned int execute (function *) final override
+  {
+    return rest_of_handle_final ();
+  }
 
 }; // class pass_final
 
@@ -4404,7 +4410,7 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual unsigned int execute (function *)
+  unsigned int execute (function *) final override
     {
       return rest_of_handle_shorten_branches ();
     }
@@ -4579,7 +4585,7 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual unsigned int execute (function *)
+  unsigned int execute (function *) final override
     {
       return rest_of_clean_state ();
     }
diff --git a/gcc/function.cc b/gcc/function.cc
index ad0096a43ef..0c3e4fffb05 100644
--- a/gcc/function.cc
+++ b/gcc/function.cc
@@ -2029,7 +2029,7 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual unsigned int execute (function *)
+  unsigned int execute (function *) final override
     {
       return instantiate_virtual_regs ();
     }
@@ -6516,7 +6516,7 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual unsigned int execute (function *)
+  unsigned int execute (function *) final override
     {
       return rest_of_handle_check_leaf_regs ();
     }
@@ -6617,7 +6617,7 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual unsigned int execute (function *)
+  unsigned int execute (function *) final override
     {
       return rest_of_handle_thread_prologue_and_epilogue ();
     }
@@ -6655,7 +6655,7 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual unsigned int execute (function *);
+  unsigned int execute (function *) final override;
 
 }; // class pass_zero_call_used_regs
 
@@ -6926,7 +6926,7 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual unsigned int execute (function *);
+  unsigned int execute (function *) final override;
 
 }; // class pass_match_asm_constraints
 
diff --git a/gcc/fwprop.cc b/gcc/fwprop.cc
index d12fc2f34ac..fc652ab9a1f 100644
--- a/gcc/fwprop.cc
+++ b/gcc/fwprop.cc
@@ -1029,8 +1029,8 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *) { return gate_fwprop (); }
-  virtual unsigned int execute (function *) { return fwprop (false); }
+  bool gate (function *) final override { return gate_fwprop (); }
+  unsigned int execute (function *) final override { return fwprop (false); }
 
 }; // class pass_rtl_fwprop
 
@@ -1065,8 +1065,8 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *) { return gate_fwprop (); }
-  virtual unsigned int execute (function *) { return fwprop (true); }
+  bool gate (function *) final override { return gate_fwprop (); }
+  unsigned int execute (function *) final override { return fwprop (true); }
 
 }; // class pass_rtl_fwprop_addr
 
diff --git a/gcc/gcse.cc b/gcc/gcse.cc
index b67353143a2..f06278a5534 100644
--- a/gcc/gcse.cc
+++ b/gcc/gcse.cc
@@ -4049,8 +4049,11 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *);
-  virtual unsigned int execute (function *) { return execute_rtl_pre (); }
+  bool gate (function *) final override;
+  unsigned int execute (function *)  final override
+  {
+    return execute_rtl_pre ();
+  }
 
 }; // class pass_rtl_pre
 
@@ -4099,8 +4102,11 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *);
-  virtual unsigned int execute (function *) { return execute_rtl_hoist (); }
+  bool gate (function *) final override;
+  unsigned int execute (function *) final override
+  {
+    return execute_rtl_hoist ();
+  }
 
 }; // class pass_rtl_hoist
 
diff --git a/gcc/gimple-harden-conditionals.cc b/gcc/gimple-harden-conditionals.cc
index 79c0a5784ba..4ca6776fca7 100644
--- a/gcc/gimple-harden-conditionals.cc
+++ b/gcc/gimple-harden-conditionals.cc
@@ -71,11 +71,15 @@ public:
   pass_harden_compares (gcc::context *ctxt)
     : gimple_opt_pass (pass_data_harden_compares, ctxt)
   {}
-  opt_pass *clone () { return new pass_harden_compares (m_ctxt); }
-  virtual bool gate (function *) {
+  opt_pass *clone ()  final override
+  {
+    return new pass_harden_compares (m_ctxt);
+  }
+  bool gate (function *) final override
+  {
     return flag_harden_compares;
   }
-  virtual unsigned int execute (function *);
+  unsigned int execute (function *) final override;
 };
 
 /* Define a pass to harden conditionals in branches.  This pass must
@@ -102,11 +106,15 @@ public:
   pass_harden_conditional_branches (gcc::context *ctxt)
     : gimple_opt_pass (pass_data_harden_conditional_branches, ctxt)
   {}
-  opt_pass *clone () { return new pass_harden_conditional_branches (m_ctxt); }
-  virtual bool gate (function *) {
+  opt_pass *clone () final override
+  {
+    return new pass_harden_conditional_branches (m_ctxt);
+  }
+  bool gate (function *) final override
+  {
     return flag_harden_conditional_branches;
   }
-  virtual unsigned int execute (function *);
+  unsigned int execute (function *) final override;
 };
 
 }
diff --git a/gcc/gimple-if-to-switch.cc b/gcc/gimple-if-to-switch.cc
index 5dcfe5b77e0..c89aef34381 100644
--- a/gcc/gimple-if-to-switch.cc
+++ b/gcc/gimple-if-to-switch.cc
@@ -478,13 +478,13 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *)
+  bool gate (function *) final override
   {
     return (jump_table_cluster::is_enabled ()
 	    || bit_test_cluster::is_enabled ());
   }
 
-  virtual unsigned int execute (function *);
+  unsigned int execute (function *) final override;
 
 }; // class pass_if_to_switch
 
diff --git a/gcc/gimple-isel.cc b/gcc/gimple-isel.cc
index 44d086d8b28..aa9c1290735 100644
--- a/gcc/gimple-isel.cc
+++ b/gcc/gimple-isel.cc
@@ -355,12 +355,12 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *)
+  bool gate (function *) final override
     {
       return true;
     }
 
-  virtual unsigned int execute (function *fun)
+  unsigned int execute (function *fun) final override
     {
       return gimple_expand_vec_exprs (fun);
     }
diff --git a/gcc/gimple-laddress.cc b/gcc/gimple-laddress.cc
index 13c7858e161..11754dac5c3 100644
--- a/gcc/gimple-laddress.cc
+++ b/gcc/gimple-laddress.cc
@@ -66,9 +66,9 @@ public:
   {}
 
   /* opt_pass methods: */
-  opt_pass * clone () { return new pass_laddress (m_ctxt); }
-  virtual bool gate (function *) { return optimize != 0; }
-  virtual unsigned int execute (function *);
+  opt_pass * clone () final override { return new pass_laddress (m_ctxt); }
+  bool gate (function *) final override { return optimize != 0; }
+  unsigned int execute (function *) final override;
 
 }; // class pass_laddress
 
diff --git a/gcc/gimple-loop-interchange.cc b/gcc/gimple-loop-interchange.cc
index 53adc02acc2..5f59730be4c 100644
--- a/gcc/gimple-loop-interchange.cc
+++ b/gcc/gimple-loop-interchange.cc
@@ -1703,9 +1703,9 @@ public:
   {}
 
   /* opt_pass methods: */
-  opt_pass * clone () { return new pass_linterchange (m_ctxt); }
-  virtual bool gate (function *) { return flag_loop_interchange; }
-  virtual unsigned int execute (function *);
+  opt_pass * clone () final override { return new pass_linterchange (m_ctxt); }
+  bool gate (function *) final override { return flag_loop_interchange; }
+  unsigned int execute (function *) final override;
 
 }; // class pass_linterchange
 
diff --git a/gcc/gimple-loop-jam.cc b/gcc/gimple-loop-jam.cc
index e33dd9091df..9b18b52a54c 100644
--- a/gcc/gimple-loop-jam.cc
+++ b/gcc/gimple-loop-jam.cc
@@ -641,8 +641,8 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *) { return flag_unroll_jam != 0; }
-  virtual unsigned int execute (function *);
+  bool gate (function *) final override { return flag_unroll_jam != 0; }
+  unsigned int execute (function *) final override;
 
 };
 
diff --git a/gcc/gimple-loop-versioning.cc b/gcc/gimple-loop-versioning.cc
index ab02bdd4b15..6bcf6eba691 100644
--- a/gcc/gimple-loop-versioning.cc
+++ b/gcc/gimple-loop-versioning.cc
@@ -1782,8 +1782,11 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *) { return flag_version_loops_for_strides; }
-  virtual unsigned int execute (function *);
+  bool gate (function *) final override
+  {
+    return flag_version_loops_for_strides;
+  }
+  unsigned int execute (function *) final override;
 };
 
 unsigned int
diff --git a/gcc/gimple-low.cc b/gcc/gimple-low.cc
index 2ec19d5657d..4cd27dd19b0 100644
--- a/gcc/gimple-low.cc
+++ b/gcc/gimple-low.cc
@@ -192,7 +192,10 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual unsigned int execute (function *) { return lower_function_body (); }
+  unsigned int execute (function *) final override
+  {
+    return lower_function_body ();
+  }
 
 }; // class pass_lower_cf
 
diff --git a/gcc/gimple-ssa-backprop.cc b/gcc/gimple-ssa-backprop.cc
index 74f98111256..55986ddbfe3 100644
--- a/gcc/gimple-ssa-backprop.cc
+++ b/gcc/gimple-ssa-backprop.cc
@@ -945,9 +945,9 @@ public:
   {}
 
   /* opt_pass methods: */
-  opt_pass * clone () { return new pass_backprop (m_ctxt); }
-  virtual bool gate (function *) { return flag_ssa_backprop; }
-  virtual unsigned int execute (function *);
+  opt_pass * clone () final override { return new pass_backprop (m_ctxt); }
+  bool gate (function *) final override { return flag_ssa_backprop; }
+  unsigned int execute (function *) final override;
 
 }; // class pass_backprop
 
diff --git a/gcc/gimple-ssa-evrp.cc b/gcc/gimple-ssa-evrp.cc
index 20388ed5431..793a3ea1f19 100644
--- a/gcc/gimple-ssa-evrp.cc
+++ b/gcc/gimple-ssa-evrp.cc
@@ -377,12 +377,12 @@ public:
     {}
 
   /* opt_pass methods: */
-  opt_pass * clone () { return new pass_early_vrp (m_ctxt); }
-  virtual bool gate (function *)
+  opt_pass * clone () final override { return new pass_early_vrp (m_ctxt); }
+  bool gate (function *) final override
     {
       return flag_tree_vrp != 0;
     }
-  virtual unsigned int execute (function *)
+  unsigned int execute (function *) final override
     { return execute_early_vrp (); }
 
 }; // class pass_vrp
diff --git a/gcc/gimple-ssa-isolate-paths.cc b/gcc/gimple-ssa-isolate-paths.cc
index cc0ed9760a0..87ecd19ef4a 100644
--- a/gcc/gimple-ssa-isolate-paths.cc
+++ b/gcc/gimple-ssa-isolate-paths.cc
@@ -969,8 +969,11 @@ public:
   {}
 
   /* opt_pass methods: */
-  opt_pass * clone () { return new pass_isolate_erroneous_paths (m_ctxt); }
-  virtual bool gate (function *)
+  opt_pass * clone () final override
+  {
+    return new pass_isolate_erroneous_paths (m_ctxt);
+  }
+  bool gate (function *) final override
     {
       /* If we do not have a suitable builtin function for the trap statement,
 	 then do not perform the optimization.  */
@@ -979,7 +982,7 @@ public:
 	      || warn_null_dereference);
     }
 
-  virtual unsigned int execute (function *)
+  unsigned int execute (function *) final override
     {
       return gimple_ssa_isolate_erroneous_paths ();
     }
diff --git a/gcc/gimple-ssa-nonnull-compare.cc b/gcc/gimple-ssa-nonnull-compare.cc
index cc52b914258..f9ce8c7a083 100644
--- a/gcc/gimple-ssa-nonnull-compare.cc
+++ b/gcc/gimple-ssa-nonnull-compare.cc
@@ -126,9 +126,9 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *) { return warn_nonnull_compare; }
+  bool gate (function *) final override { return warn_nonnull_compare; }
 
-  virtual unsigned int execute (function *);
+  unsigned int execute (function *) final override;
 
 }; // class pass_warn_nonnull_compare
 
diff --git a/gcc/gimple-ssa-split-paths.cc b/gcc/gimple-ssa-split-paths.cc
index 6abe1d51400..f2e43e52c95 100644
--- a/gcc/gimple-ssa-split-paths.cc
+++ b/gcc/gimple-ssa-split-paths.cc
@@ -579,9 +579,12 @@ class pass_split_paths : public gimple_opt_pass
       : gimple_opt_pass (pass_data_split_paths, ctxt)
     {}
    /* opt_pass methods: */
-   opt_pass * clone () { return new pass_split_paths (m_ctxt); }
-   virtual bool gate (function *) { return gate_split_paths (); }
-   virtual unsigned int execute (function *) { return execute_split_paths (); }
+  opt_pass * clone () final override { return new pass_split_paths (m_ctxt); }
+  bool gate (function *) final override { return gate_split_paths (); }
+  unsigned int execute (function *) final override
+  {
+    return execute_split_paths ();
+  }
 
 }; // class pass_split_paths
 
diff --git a/gcc/gimple-ssa-store-merging.cc b/gcc/gimple-ssa-store-merging.cc
index b952ce57917..0640168bcc4 100644
--- a/gcc/gimple-ssa-store-merging.cc
+++ b/gcc/gimple-ssa-store-merging.cc
@@ -1037,12 +1037,12 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *)
+  bool gate (function *) final override
     {
       return flag_expensive_optimizations && optimize && BITS_PER_UNIT == 8;
     }
 
-  virtual unsigned int execute (function *);
+  unsigned int execute (function *) final override;
 
 }; // class pass_optimize_bswap
 
@@ -2433,8 +2433,8 @@ public:
   /* Pass not supported for PDP-endian, nor for insane hosts or
      target character sizes where native_{encode,interpret}_expr
      doesn't work properly.  */
-  virtual bool
-  gate (function *)
+  bool
+  gate (function *) final override
   {
     return flag_store_merging
 	   && BYTES_BIG_ENDIAN == WORDS_BIG_ENDIAN
@@ -2442,7 +2442,7 @@ public:
 	   && BITS_PER_UNIT == 8;
   }
 
-  virtual unsigned int execute (function *);
+  unsigned int execute (function *) final override;
 
 private:
   hash_map<tree_operand_hash, class imm_store_chain_info *> m_stores;
diff --git a/gcc/gimple-ssa-strength-reduction.cc b/gcc/gimple-ssa-strength-reduction.cc
index dad73d31874..2b559e96fc8 100644
--- a/gcc/gimple-ssa-strength-reduction.cc
+++ b/gcc/gimple-ssa-strength-reduction.cc
@@ -4002,8 +4002,8 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *) { return flag_tree_slsr; }
-  virtual unsigned int execute (function *);
+  bool gate (function *) final override { return flag_tree_slsr; }
+  unsigned int execute (function *) final override;
 
 }; // class pass_strength_reduction
 
diff --git a/gcc/gimple-ssa-warn-access.cc b/gcc/gimple-ssa-warn-access.cc
index 9357a4e576a..1f70cbdb884 100644
--- a/gcc/gimple-ssa-warn-access.cc
+++ b/gcc/gimple-ssa-warn-access.cc
@@ -2069,13 +2069,13 @@ class pass_waccess : public gimple_opt_pass
 
   ~pass_waccess ();
 
-  opt_pass *clone ();
+  opt_pass *clone () final override;
 
-  virtual bool gate (function *);
+  bool gate (function *) final override;
 
-  void set_pass_param (unsigned, bool);
+  void set_pass_param (unsigned, bool) final override;
 
-  virtual unsigned int execute (function *);
+  unsigned int execute (function *) final override;
 
 private:
   /* Not copyable or assignable.  */
diff --git a/gcc/gimple-ssa-warn-alloca.cc b/gcc/gimple-ssa-warn-alloca.cc
index 273b88ec141..83a241a3a4b 100644
--- a/gcc/gimple-ssa-warn-alloca.cc
+++ b/gcc/gimple-ssa-warn-alloca.cc
@@ -58,8 +58,8 @@ public:
   pass_walloca (gcc::context *ctxt)
     : gimple_opt_pass(pass_data_walloca, ctxt), xlimit_certain_p (false)
   {}
-  opt_pass *clone () { return new pass_walloca (m_ctxt); }
-  void set_pass_param (unsigned int n, bool param)
+  opt_pass *clone () final override { return new pass_walloca (m_ctxt); }
+  void set_pass_param (unsigned int n, bool param) final override
     {
       gcc_assert (n == 0);
       // Set to true to enable only warnings for alloca calls that
@@ -69,8 +69,8 @@ public:
       // the "may be too large" kind.
       xlimit_certain_p = param;
     }
-  virtual bool gate (function *);
-  virtual unsigned int execute (function *);
+  bool gate (function *) final override;
+  unsigned int execute (function *) final override;
 
  private:
   // Set to TRUE the first time we run this pass on a function.
diff --git a/gcc/gimple-ssa-warn-restrict.cc b/gcc/gimple-ssa-warn-restrict.cc
index b678e806da3..2a1afcbb0fc 100644
--- a/gcc/gimple-ssa-warn-restrict.cc
+++ b/gcc/gimple-ssa-warn-restrict.cc
@@ -64,8 +64,8 @@ class pass_wrestrict : public gimple_opt_pass
  public:
   pass_wrestrict (gcc::context *);
 
-  virtual bool gate (function *);
-  virtual unsigned int execute (function *);
+  bool gate (function *) final override;
+  unsigned int execute (function *) final override;
 
   void check_call (gimple *);
 
diff --git a/gcc/gimple-warn-recursion.cc b/gcc/gimple-warn-recursion.cc
index 91a3cdbacd4..9b04899cf78 100644
--- a/gcc/gimple-warn-recursion.cc
+++ b/gcc/gimple-warn-recursion.cc
@@ -52,9 +52,9 @@ public:
   pass_warn_recursion (gcc::context *);
 
 private:
-  virtual bool gate (function *) { return warn_infinite_recursion; }
+  bool gate (function *) final override { return warn_infinite_recursion; }
 
-  virtual unsigned int execute (function *);
+  unsigned int execute (function *) final override;
 
   bool find_function_exit (basic_block);
 
diff --git a/gcc/graphite.cc b/gcc/graphite.cc
index ab8683b5b41..a88b13c0219 100644
--- a/gcc/graphite.cc
+++ b/gcc/graphite.cc
@@ -574,7 +574,7 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *) { return gate_graphite_transforms (); }
+  bool gate (function *) final override { return gate_graphite_transforms (); }
 
 }; // class pass_graphite
 
@@ -609,8 +609,11 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *) { return gate_graphite_transforms (); }
-  virtual unsigned int execute (function *fun) { return graphite_transforms (fun); }
+  bool gate (function *) final override { return gate_graphite_transforms (); }
+  unsigned int execute (function *fun) final override
+  {
+    return graphite_transforms (fun);
+  }
 
 }; // class pass_graphite_transforms
 
diff --git a/gcc/ifcvt.cc b/gcc/ifcvt.cc
index b983e87389f..28b153cf2ae 100644
--- a/gcc/ifcvt.cc
+++ b/gcc/ifcvt.cc
@@ -5933,12 +5933,12 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *)
+  bool gate (function *) final override
     {
       return (optimize > 0) && dbg_cnt (if_conversion);
     }
 
-  virtual unsigned int execute (function *)
+  unsigned int execute (function *) final override
     {
       return rest_of_handle_if_conversion ();
     }
@@ -5980,13 +5980,13 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *)
+  bool gate (function *) final override
     {
       return optimize > 0 && flag_if_conversion
 	&& dbg_cnt (if_after_combine);
     }
 
-  virtual unsigned int execute (function *)
+  unsigned int execute (function *) final override
     {
       if_convert (true);
       return 0;
@@ -6026,13 +6026,13 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *)
+  bool gate (function *) final override
     {
       return optimize > 0 && flag_if_conversion2
 	&& dbg_cnt (if_after_reload);
     }
 
-  virtual unsigned int execute (function *)
+  unsigned int execute (function *) final override
     {
       if_convert (true);
       return 0;
diff --git a/gcc/init-regs.cc b/gcc/init-regs.cc
index 220ef705997..652befefdaa 100644
--- a/gcc/init-regs.cc
+++ b/gcc/init-regs.cc
@@ -153,8 +153,8 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *) { return optimize > 0; }
-  virtual unsigned int execute (function *)
+  bool gate (function *) final override { return optimize > 0; }
+  unsigned int execute (function *) final override
     {
       initialize_uninitialized_regs ();
       return 0;
diff --git a/gcc/ipa-comdats.cc b/gcc/ipa-comdats.cc
index 566faf3cc1f..da792065ed3 100644
--- a/gcc/ipa-comdats.cc
+++ b/gcc/ipa-comdats.cc
@@ -420,8 +420,8 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *);
-  virtual unsigned int execute (function *) { return ipa_comdats (); }
+  bool gate (function *) final override;
+  unsigned int execute (function *) final override { return ipa_comdats (); }
 
 }; // class pass_ipa_comdats
 
diff --git a/gcc/ipa-cp.cc b/gcc/ipa-cp.cc
index 152fe7244f7..38a21b17e39 100644
--- a/gcc/ipa-cp.cc
+++ b/gcc/ipa-cp.cc
@@ -6659,14 +6659,14 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *)
+  bool gate (function *) final override
     {
       /* FIXME: We should remove the optimize check after we ensure we never run
 	 IPA passes when not optimizing.  */
       return (flag_ipa_cp && optimize) || in_lto_p;
     }
 
-  virtual unsigned int execute (function *) { return ipcp_driver (); }
+  unsigned int execute (function *) final override { return ipcp_driver (); }
 
 }; // class pass_ipa_cp
 
diff --git a/gcc/ipa-devirt.cc b/gcc/ipa-devirt.cc
index 9f1442dc3cc..412ca14f66b 100644
--- a/gcc/ipa-devirt.cc
+++ b/gcc/ipa-devirt.cc
@@ -3969,7 +3969,7 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *)
+  bool gate (function *) final override
     {
       /* In LTO, always run the IPA passes and decide on function basis if the
 	 pass is enabled.  */
@@ -3982,7 +3982,7 @@ public:
 	      && optimize);
     }
 
-  virtual unsigned int execute (function *) { return ipa_devirt (); }
+  unsigned int execute (function *) final override { return ipa_devirt (); }
 
 }; // class pass_ipa_devirt
 
@@ -4361,12 +4361,12 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *)
+  bool gate (function *) final override
     {
       return (in_lto_p || flag_lto);
     }
 
-  virtual unsigned int execute (function *)
+  unsigned int execute (function *) final override
     {
       return 0;
     }
diff --git a/gcc/ipa-fnsummary.cc b/gcc/ipa-fnsummary.cc
index b12e7a1124d..832794fd5dc 100644
--- a/gcc/ipa-fnsummary.cc
+++ b/gcc/ipa-fnsummary.cc
@@ -4846,8 +4846,11 @@ public:
   {}
 
   /* opt_pass methods: */
-  opt_pass * clone () { return new pass_local_fn_summary (m_ctxt); }
-  virtual unsigned int execute (function *)
+  opt_pass * clone () final override
+  {
+    return new pass_local_fn_summary (m_ctxt);
+  }
+  unsigned int execute (function *) final override
     {
       return compute_fn_summary_for_current ();
     }
@@ -4889,14 +4892,17 @@ public:
   {}
 
   /* opt_pass methods: */
-  opt_pass *clone () { return new pass_ipa_free_fn_summary (m_ctxt); }
-  void set_pass_param (unsigned int n, bool param)
+  opt_pass *clone () final override
+  {
+    return new pass_ipa_free_fn_summary (m_ctxt);
+  }
+  void set_pass_param (unsigned int n, bool param) final override
     {
       gcc_assert (n == 0);
       small_p = param;
     }
-  virtual bool gate (function *) { return true; }
-  virtual unsigned int execute (function *)
+  bool gate (function *) final override { return true; }
+  unsigned int execute (function *) final override
     {
       ipa_free_fn_summary ();
       /* Free ipa-prop structures if they are no longer needed.  */
@@ -4950,7 +4956,7 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual unsigned int execute (function *) { return 0; }
+  unsigned int execute (function *) final override { return 0; }
 
 }; // class pass_ipa_fn_summary
 
diff --git a/gcc/ipa-free-lang-data.cc b/gcc/ipa-free-lang-data.cc
index f99f7be1c58..ccdbf849c25 100644
--- a/gcc/ipa-free-lang-data.cc
+++ b/gcc/ipa-free-lang-data.cc
@@ -1173,7 +1173,7 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual unsigned int execute (function *) { return free_lang_data (); }
+  unsigned int execute (function *) final override { return free_lang_data (); }
 
 }; // class pass_ipa_free_lang_data
 
diff --git a/gcc/ipa-icf.cc b/gcc/ipa-icf.cc
index 765ae746745..a8a162268ee 100644
--- a/gcc/ipa-icf.cc
+++ b/gcc/ipa-icf.cc
@@ -3637,12 +3637,12 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *)
+  bool gate (function *) final override
   {
     return in_lto_p || flag_ipa_icf_variables || flag_ipa_icf_functions;
   }
 
-  virtual unsigned int execute (function *)
+  unsigned int execute (function *) final override
   {
     return ipa_icf_driver();
   }
diff --git a/gcc/ipa-inline.cc b/gcc/ipa-inline.cc
index 22a009b7435..14969198cde 100644
--- a/gcc/ipa-inline.cc
+++ b/gcc/ipa-inline.cc
@@ -3100,7 +3100,7 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual unsigned int execute (function *);
+  unsigned int execute (function *) final override;
 
 }; // class pass_early_inline
 
@@ -3150,7 +3150,7 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual unsigned int execute (function *) { return ipa_inline (); }
+  unsigned int execute (function *) final override { return ipa_inline (); }
 
 }; // class pass_ipa_inline
 
diff --git a/gcc/ipa-modref.cc b/gcc/ipa-modref.cc
index 556816ab429..7c1f974bc7a 100644
--- a/gcc/ipa-modref.cc
+++ b/gcc/ipa-modref.cc
@@ -3508,15 +3508,15 @@ class pass_modref : public gimple_opt_pass
 	: gimple_opt_pass (pass_data_modref, ctxt) {}
 
     /* opt_pass methods: */
-    opt_pass *clone ()
+    opt_pass *clone () final override
     {
       return new pass_modref (m_ctxt);
     }
-    virtual bool gate (function *)
+    bool gate (function *) final override
     {
       return flag_ipa_modref;
     }
-    virtual unsigned int execute (function *);
+    unsigned int execute (function *) final override;
 };
 
 /* Encode TT to the output block OB using the summary streaming API.  */
@@ -4170,12 +4170,12 @@ public:
   {}
 
   /* opt_pass methods: */
-  opt_pass *clone () { return new pass_ipa_modref (m_ctxt); }
-  virtual bool gate (function *)
+  opt_pass *clone () final override { return new pass_ipa_modref (m_ctxt); }
+  bool gate (function *) final override
   {
     return true;
   }
-  virtual unsigned int execute (function *);
+  unsigned int execute (function *) final override;
 
 };
 
diff --git a/gcc/ipa-profile.cc b/gcc/ipa-profile.cc
index b74d77f2c95..496f292acba 100644
--- a/gcc/ipa-profile.cc
+++ b/gcc/ipa-profile.cc
@@ -1053,8 +1053,8 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *) { return flag_ipa_profile || in_lto_p; }
-  virtual unsigned int execute (function *) { return ipa_profile (); }
+  bool gate (function *) final override { return flag_ipa_profile || in_lto_p; }
+  unsigned int execute (function *) final override { return ipa_profile (); }
 
 }; // class pass_ipa_profile
 
diff --git a/gcc/ipa-pure-const.cc b/gcc/ipa-pure-const.cc
index 2b4950a5969..0e55fc4bfc5 100644
--- a/gcc/ipa-pure-const.cc
+++ b/gcc/ipa-pure-const.cc
@@ -168,8 +168,8 @@ public:
   pass_ipa_pure_const(gcc::context *ctxt);
 
   /* opt_pass methods: */
-  bool gate (function *) { return gate_pure_const (); }
-  unsigned int execute (function *fun);
+  bool gate (function *) final override { return gate_pure_const (); }
+  unsigned int execute (function *fun) final override;
 
   void register_hooks (void);
 
@@ -2154,9 +2154,12 @@ public:
   {}
 
   /* opt_pass methods: */
-  opt_pass * clone () { return new pass_local_pure_const (m_ctxt); }
-  virtual bool gate (function *) { return gate_pure_const (); }
-  virtual unsigned int execute (function *);
+  opt_pass * clone () final override
+  {
+    return new pass_local_pure_const (m_ctxt);
+  }
+  bool gate (function *) final override { return gate_pure_const (); }
+  unsigned int execute (function *) final override;
 
 }; // class pass_local_pure_const
 
@@ -2270,8 +2273,11 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *) { return warn_suggest_attribute_noreturn; }
-  virtual unsigned int execute (function *fun)
+  bool gate (function *) final override
+  {
+    return warn_suggest_attribute_noreturn;
+  }
+  unsigned int execute (function *fun) final override
     {
       if (!TREE_THIS_VOLATILE (current_function_decl)
 	  && EDGE_COUNT (EXIT_BLOCK_PTR_FOR_FN (fun)->preds) == 0)
@@ -2316,9 +2322,9 @@ public:
   {}
 
   /* opt_pass methods: */
-  opt_pass * clone () { return new pass_nothrow (m_ctxt); }
-  virtual bool gate (function *) { return optimize; }
-  virtual unsigned int execute (function *);
+  opt_pass * clone () final override { return new pass_nothrow (m_ctxt); }
+  bool gate (function *) final override { return optimize; }
+  unsigned int execute (function *) final override;
 
 }; // class pass_nothrow
 
diff --git a/gcc/ipa-reference.cc b/gcc/ipa-reference.cc
index 67e0c85a95e..b5a2350ce72 100644
--- a/gcc/ipa-reference.cc
+++ b/gcc/ipa-reference.cc
@@ -1299,14 +1299,14 @@ public:
     {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *)
+  bool gate (function *) final override
     {
       return ((in_lto_p || flag_ipa_reference)
 	      /* Don't bother doing anything if the program has errors.  */
 	      && !seen_error ());
     }
 
-  virtual unsigned int execute (function *) { return propagate (); }
+  unsigned int execute (function *) final override { return propagate (); }
 
 }; // class pass_ipa_reference
 
diff --git a/gcc/ipa-split.cc b/gcc/ipa-split.cc
index 60021bad13c..16734617d03 100644
--- a/gcc/ipa-split.cc
+++ b/gcc/ipa-split.cc
@@ -1915,8 +1915,8 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *);
-  virtual unsigned int execute (function *)
+  bool gate (function *) final override;
+  unsigned int execute (function *) final override
     {
       return execute_split_functions ();
     }
@@ -1974,8 +1974,8 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *);
-  virtual unsigned int execute (function *)
+  bool gate (function *) final override;
+  unsigned int execute (function *) final override
     {
       return execute_feedback_split_functions ();
     }
diff --git a/gcc/ipa-sra.cc b/gcc/ipa-sra.cc
index 261a720858f..4f705a3febf 100644
--- a/gcc/ipa-sra.cc
+++ b/gcc/ipa-sra.cc
@@ -4049,14 +4049,17 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *)
+  bool gate (function *) final override
     {
       /* TODO: We should remove the optimize check after we ensure we never run
 	 IPA passes when not optimizing.  */
       return (flag_ipa_sra && optimize);
     }
 
-  virtual unsigned int execute (function *) { return ipa_sra_analysis (); }
+  unsigned int execute (function *)  final override
+  {
+    return ipa_sra_analysis ();
+  }
 
 }; // class pass_ipa_sra
 
diff --git a/gcc/ipa-visibility.cc b/gcc/ipa-visibility.cc
index e95a0dd252f..8a27e7bcdfd 100644
--- a/gcc/ipa-visibility.cc
+++ b/gcc/ipa-visibility.cc
@@ -959,12 +959,12 @@ public:
 
   /* opt_pass methods: */
 
-  virtual bool gate (function *)
+  bool gate (function *) final override
     {
       /* Do not re-run on ltrans stage.  */
       return !flag_ltrans;
     }
-  virtual unsigned int execute (function *)
+  unsigned int execute (function *) final override
     {
       return whole_program_function_and_variable_visibility ();
     }
@@ -988,7 +988,7 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual unsigned int execute (function *)
+  unsigned int execute (function *) final override
     {
       return function_and_variable_visibility (flag_whole_program && !flag_lto);
     }
diff --git a/gcc/ipa.cc b/gcc/ipa.cc
index f53f15f5f0a..c01dca17bec 100644
--- a/gcc/ipa.cc
+++ b/gcc/ipa.cc
@@ -1343,8 +1343,11 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *);
-  virtual unsigned int execute (function *) { return ipa_cdtor_merge (); }
+  bool gate (function *) final override;
+  unsigned int execute (function *) final override
+  {
+    return ipa_cdtor_merge ();
+  }
 
 }; // class pass_ipa_cdtor_merge
 
@@ -1566,7 +1569,7 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual unsigned int execute (function *) { return ipa_single_use (); }
+  unsigned int execute (function *) final override { return ipa_single_use (); }
 
 }; // class pass_ipa_single_use
 
diff --git a/gcc/ira.cc b/gcc/ira.cc
index e3b3c549120..42c9cead9f8 100644
--- a/gcc/ira.cc
+++ b/gcc/ira.cc
@@ -6074,11 +6074,11 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *)
+  bool gate (function *) final override
     {
       return !targetm.no_register_allocation;
     }
-  virtual unsigned int execute (function *)
+  unsigned int execute (function *) final override
     {
       ira (dump_file);
       return 0;
@@ -6117,11 +6117,11 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *)
+  bool gate (function *) final override
     {
       return !targetm.no_register_allocation;
     }
-  virtual unsigned int execute (function *)
+  unsigned int execute (function *) final override
     {
       do_reload ();
       return 0;
diff --git a/gcc/jump.cc b/gcc/jump.cc
index 332f86878e1..e6207169be0 100644
--- a/gcc/jump.cc
+++ b/gcc/jump.cc
@@ -182,7 +182,10 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual unsigned int execute (function *) { return cleanup_barriers (); }
+  unsigned int execute (function *) final override
+  {
+    return cleanup_barriers ();
+  }
 
 }; // class pass_cleanup_barriers
 
diff --git a/gcc/loop-init.cc b/gcc/loop-init.cc
index 1e4f6cfd7fb..648aa290916 100644
--- a/gcc/loop-init.cc
+++ b/gcc/loop-init.cc
@@ -357,7 +357,7 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *);
+  bool gate (function *) final override;
 
 }; // class pass_loop2
 
@@ -429,7 +429,7 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual unsigned int execute (function *) { return rtl_loop_init (); }
+  unsigned int execute (function *) final override { return rtl_loop_init (); }
 
 }; // class pass_rtl_loop_init
 
@@ -467,7 +467,7 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual unsigned int execute (function *);
+  unsigned int execute (function *) final override;
 
 }; // class pass_rtl_loop_done
 
@@ -523,8 +523,8 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *) { return flag_move_loop_invariants; }
-  virtual unsigned int execute (function *fun)
+  bool gate (function *) final override { return flag_move_loop_invariants; }
+  unsigned int execute (function *fun) final override
     {
       if (number_of_loops (fun) > 1)
 	move_loop_invariants ();
@@ -565,12 +565,12 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *)
+  bool gate (function *) final override
     {
       return (flag_unroll_loops || flag_unroll_all_loops || cfun->has_unroll);
     }
 
-  virtual unsigned int execute (function *);
+  unsigned int execute (function *) final override;
 
 }; // class pass_rtl_unroll_loops
 
@@ -625,8 +625,8 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *);
-  virtual unsigned int execute (function *);
+  bool gate (function *) final override;
+  unsigned int execute (function *) final override;
 
 }; // class pass_rtl_doloop
 
diff --git a/gcc/lower-subreg.cc b/gcc/lower-subreg.cc
index d30bbeeabda..03e9326c663 100644
--- a/gcc/lower-subreg.cc
+++ b/gcc/lower-subreg.cc
@@ -1769,8 +1769,8 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *) { return flag_split_wide_types != 0; }
-  virtual unsigned int execute (function *)
+  bool gate (function *) final override { return flag_split_wide_types != 0; }
+  unsigned int execute (function *) final override
     {
       decompose_multiword_subregs (false);
       return 0;
@@ -1811,9 +1811,11 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *) { return flag_split_wide_types
-					  && flag_split_wide_types_early; }
-  virtual unsigned int execute (function *)
+  bool gate (function *) final override
+  {
+    return flag_split_wide_types && flag_split_wide_types_early;
+  }
+  unsigned int execute (function *) final override
     {
       decompose_multiword_subregs (true);
       return 0;
@@ -1854,8 +1856,8 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *) { return flag_split_wide_types; }
-  virtual unsigned int execute (function *)
+  bool gate (function *) final override { return flag_split_wide_types; }
+  unsigned int execute (function *) final override
     {
       decompose_multiword_subregs (true);
       return 0;
diff --git a/gcc/mode-switching.cc b/gcc/mode-switching.cc
index 6e3f1dc65e2..b0f6e7cedd4 100644
--- a/gcc/mode-switching.cc
+++ b/gcc/mode-switching.cc
@@ -893,8 +893,8 @@ public:
   /* opt_pass methods: */
   /* The epiphany backend creates a second instance of this pass, so we need
      a clone method.  */
-  opt_pass * clone () { return new pass_mode_switching (m_ctxt); }
-  virtual bool gate (function *)
+  opt_pass * clone () final override { return new pass_mode_switching (m_ctxt); }
+  bool gate (function *) final override
     {
 #ifdef OPTIMIZE_MODE_SWITCHING
       return true;
@@ -903,7 +903,7 @@ public:
 #endif
     }
 
-  virtual unsigned int execute (function *)
+  unsigned int execute (function *) final override
     {
 #ifdef OPTIMIZE_MODE_SWITCHING
       optimize_mode_switching ();
diff --git a/gcc/modulo-sched.cc b/gcc/modulo-sched.cc
index 1e1fa7055a2..f78d791cb01 100644
--- a/gcc/modulo-sched.cc
+++ b/gcc/modulo-sched.cc
@@ -3338,12 +3338,12 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *)
+  bool gate (function *) final override
 {
   return (optimize > 0 && flag_modulo_sched);
 }
 
-  virtual unsigned int execute (function *);
+  unsigned int execute (function *) final override;
 
 }; // class pass_sms
 
diff --git a/gcc/multiple_target.cc b/gcc/multiple_target.cc
index 7fe02fb55c8..3e2d26882c8 100644
--- a/gcc/multiple_target.cc
+++ b/gcc/multiple_target.cc
@@ -526,8 +526,11 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *);
-  virtual unsigned int execute (function *) { return ipa_target_clone (); }
+  bool gate (function *) final override;
+  unsigned int execute (function *) final override
+  {
+    return ipa_target_clone ();
+  }
 };
 
 bool
diff --git a/gcc/omp-expand.cc b/gcc/omp-expand.cc
index 9fcc67a3448..3d48e1df175 100644
--- a/gcc/omp-expand.cc
+++ b/gcc/omp-expand.cc
@@ -10574,7 +10574,7 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual unsigned int execute (function *)
+  unsigned int execute (function *) final override
     {
       bool gate = ((flag_openacc != 0 || flag_openmp != 0
 		    || flag_openmp_simd != 0)
@@ -10621,12 +10621,18 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *fun)
+  bool gate (function *fun) final override
     {
       return !(fun->curr_properties & PROP_gimple_eomp);
     }
-  virtual unsigned int execute (function *) { return execute_expand_omp (); }
-  opt_pass * clone () { return new pass_expand_omp_ssa (m_ctxt); }
+  unsigned int execute (function *) final override
+  {
+    return execute_expand_omp ();
+  }
+  opt_pass * clone () final override
+  {
+    return new pass_expand_omp_ssa (m_ctxt);
+  }
 
 }; // class pass_expand_omp_ssa
 
diff --git a/gcc/omp-low.cc b/gcc/omp-low.cc
index c83af6c3865..e00788f0ea1 100644
--- a/gcc/omp-low.cc
+++ b/gcc/omp-low.cc
@@ -14594,7 +14594,10 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual unsigned int execute (function *) { return execute_lower_omp (); }
+  unsigned int execute (function *) final override
+  {
+    return execute_lower_omp ();
+  }
 
 }; // class pass_lower_omp
 
@@ -14902,11 +14905,11 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *)
+  bool gate (function *) final override
   {
     return flag_openacc || flag_openmp || flag_openmp_simd;
   }
-  virtual unsigned int execute (function *)
+  unsigned int execute (function *) final override
     {
       return diagnose_omp_structured_block_errors ();
     }
diff --git a/gcc/omp-oacc-kernels-decompose.cc b/gcc/omp-oacc-kernels-decompose.cc
index ec9b0faab0a..524060e2fca 100644
--- a/gcc/omp-oacc-kernels-decompose.cc
+++ b/gcc/omp-oacc-kernels-decompose.cc
@@ -1615,12 +1615,12 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *)
+  bool gate (function *) final override
   {
     return (flag_openacc
 	    && param_openacc_kernels == OPENACC_KERNELS_DECOMPOSE);
   }
-  virtual unsigned int execute (function *)
+  unsigned int execute (function *) final override
   {
     return omp_oacc_kernels_decompose ();
   }
diff --git a/gcc/omp-oacc-neuter-broadcast.cc b/gcc/omp-oacc-neuter-broadcast.cc
index 81e3223a94c..b6177794cde 100644
--- a/gcc/omp-oacc-neuter-broadcast.cc
+++ b/gcc/omp-oacc-neuter-broadcast.cc
@@ -1945,7 +1945,7 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *fun)
+  bool gate (function *fun) final override
   {
     if (!flag_openacc)
       return false;
@@ -1961,7 +1961,7 @@ public:
     return true;
   }
 
-  virtual unsigned int execute (function *)
+  unsigned int execute (function *) final override
     {
       return execute_omp_oacc_neuter_broadcast ();
     }
diff --git a/gcc/omp-offload.cc b/gcc/omp-offload.cc
index ad4e772015e..9de04fc520c 100644
--- a/gcc/omp-offload.cc
+++ b/gcc/omp-offload.cc
@@ -2449,9 +2449,9 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *) { return flag_openacc; };
+  bool gate (function *) final override { return flag_openacc; };
 
-  virtual unsigned int execute (function *)
+  unsigned int execute (function *) final override
     {
       return execute_oacc_loop_designation ();
     }
@@ -2479,9 +2479,9 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *) { return flag_openacc; };
+  bool gate (function *) final override { return flag_openacc; };
 
-  virtual unsigned int execute (function *)
+  unsigned int execute (function *) final override
     {
       return execute_oacc_device_lower ();
     }
@@ -2713,13 +2713,13 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *fun)
+  bool gate (function *fun) final override
     {
       return (!(fun->curr_properties & PROP_gimple_lomp_dev)
 	      || (flag_openmp
 		  && cgraph_node::get (fun->decl)->calls_declare_variant_alt));
     }
-  virtual unsigned int execute (function *)
+  unsigned int execute (function *) final override
     {
       return execute_omp_device_lower ();
     }
@@ -2759,7 +2759,7 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *fun)
+  bool gate (function *fun) final override
     {
 #ifdef ACCEL_COMPILER
       return offloading_function_p (fun->decl);
@@ -2769,7 +2769,7 @@ public:
 #endif
     }
 
-  virtual unsigned execute (function *);
+  unsigned execute (function *) final override;
 };
 
 /* Callback for walk_gimple_stmt used to scan for link var operands.  */
diff --git a/gcc/omp-simd-clone.cc b/gcc/omp-simd-clone.cc
index 04fe03cde5f..32649bc3f9a 100644
--- a/gcc/omp-simd-clone.cc
+++ b/gcc/omp-simd-clone.cc
@@ -1819,8 +1819,11 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *);
-  virtual unsigned int execute (function *) { return ipa_omp_simd_clone (); }
+  bool gate (function *) final override;
+  unsigned int execute (function *) final override
+  {
+    return ipa_omp_simd_clone ();
+  }
 };
 
 bool
diff --git a/gcc/passes.cc b/gcc/passes.cc
index 36e5b4ac45f..78a07f8691a 100644
--- a/gcc/passes.cc
+++ b/gcc/passes.cc
@@ -417,13 +417,13 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *)
+  bool gate (function *) final override
     {
       /* Don't bother doing anything if the program has errors.  */
       return (!seen_error () && !in_lto_p);
     }
 
-  virtual unsigned int execute (function *)
+  unsigned int execute (function *) final override
     {
       return execute_build_ssa_passes ();
     }
@@ -451,7 +451,7 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *)
+  bool gate (function *) final override
     {
       /* Don't bother doing anything if the program has errors.  */
       return (!seen_error () && !in_lto_p);
@@ -480,7 +480,7 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *)
+  bool gate (function *) final override
     {
       /* Don't bother doing anything if the program has errors.  */
       return (!seen_error () && !in_lto_p);
@@ -531,7 +531,7 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *)
+  bool gate (function *) final override
     {
       return (optimize >= 1
 	      /* Don't bother doing anything if the program has errors.  */
@@ -571,7 +571,10 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *) { return optimize >= 1 && !optimize_debug; }
+  bool gate (function *) final override
+  {
+    return optimize >= 1 && !optimize_debug;
+  }
 
 }; // class pass_all_optimizations
 
@@ -606,7 +609,10 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *) { return optimize >= 1 && optimize_debug; }
+  bool gate (function *) final override
+  {
+    return optimize >= 1 && optimize_debug;
+  }
 
 }; // class pass_all_optimizations_g
 
@@ -641,7 +647,7 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *)
+  bool gate (function *) final override
     {
       /* Early return if there were errors.  We can run afoul of our
 	 consistency checks, and there's not really much point in fixing them.  */
@@ -681,7 +687,7 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *) { return reload_completed; }
+  bool gate (function *) final override { return reload_completed; }
 
 }; // class pass_postreload
 
@@ -716,7 +722,7 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *)
+  bool gate (function *) final override
   {
     return reload_completed || targetm.no_register_allocation;
   }
@@ -756,15 +762,15 @@ public:
   {
   }
 
-  virtual bool
-  gate (function *fun)
+  bool
+  gate (function *fun) final override
   {
     return flag_tree_slp_vectorize
 	   && (fun->pending_TODOs & PENDING_TODO_force_next_scalar_cleanup);
   }
 
-  virtual unsigned int
-  execute (function *fun)
+  unsigned int
+  execute (function *fun) final override
   {
     fun->pending_TODOs &= ~PENDING_TODO_force_next_scalar_cleanup;
     return 0;
diff --git a/gcc/postreload-gcse.cc b/gcc/postreload-gcse.cc
index fc63f0b5c77..1c795b43ca3 100644
--- a/gcc/postreload-gcse.cc
+++ b/gcc/postreload-gcse.cc
@@ -1447,13 +1447,16 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *fun)
+  bool gate (function *fun) final override
     {
       return (optimize > 0 && flag_gcse_after_reload
 	      && optimize_function_for_speed_p (fun));
     }
 
-  virtual unsigned int execute (function *) { return rest_of_handle_gcse2 (); }
+  unsigned int execute (function *) final override
+  {
+    return rest_of_handle_gcse2 ();
+  }
 
 }; // class pass_gcse2
 
diff --git a/gcc/postreload.cc b/gcc/postreload.cc
index 4a67d0d437a..d1c99fe6dc9 100644
--- a/gcc/postreload.cc
+++ b/gcc/postreload.cc
@@ -2339,9 +2339,12 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *) { return (optimize > 0 && reload_completed); }
+  bool gate (function *) final override
+  {
+    return (optimize > 0 && reload_completed);
+  }
 
-  virtual unsigned int execute (function *);
+  unsigned int execute (function *) final override;
 
 }; // class pass_postreload_cse
 
diff --git a/gcc/predict.cc b/gcc/predict.cc
index 5734e4c8516..fb9fa514fbc 100644
--- a/gcc/predict.cc
+++ b/gcc/predict.cc
@@ -4079,8 +4079,8 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *) { return flag_guess_branch_prob; }
-  virtual unsigned int execute (function *);
+  bool gate (function *) final override { return flag_guess_branch_prob; }
+  unsigned int execute (function *) final override;
 
 }; // class pass_profile
 
@@ -4233,14 +4233,17 @@ public:
   {}
 
   /* opt_pass methods: */
-  opt_pass * clone () { return new pass_strip_predict_hints (m_ctxt); }
-  void set_pass_param (unsigned int n, bool param)
+  opt_pass * clone () final override
+  {
+    return new pass_strip_predict_hints (m_ctxt);
+  }
+  void set_pass_param (unsigned int n, bool param) final override
     {
       gcc_assert (n == 0);
       early_p = param;
     }
 
-  virtual unsigned int execute (function *);
+  unsigned int execute (function *) final override;
 
 private:
   bool early_p;
diff --git a/gcc/recog.cc b/gcc/recog.cc
index cd2410ab2ae..dac172bc7c0 100644
--- a/gcc/recog.cc
+++ b/gcc/recog.cc
@@ -4358,9 +4358,12 @@ public:
   /* opt_pass methods: */
   /* The epiphany backend creates a second instance of this pass, so we need
      a clone method.  */
-  opt_pass * clone () { return new pass_peephole2 (m_ctxt); }
-  virtual bool gate (function *) { return (optimize > 0 && flag_peephole2); }
-  virtual unsigned int execute (function *)
+  opt_pass * clone () final override { return new pass_peephole2 (m_ctxt); }
+  bool gate (function *) final override
+  {
+    return (optimize > 0 && flag_peephole2);
+  }
+  unsigned int execute (function *) final override
     {
       return rest_of_handle_peephole2 ();
     }
@@ -4400,8 +4403,11 @@ public:
   /* opt_pass methods: */
   /* The epiphany backend creates a second instance of this pass, so
      we need a clone method.  */
-  opt_pass * clone () { return new pass_split_all_insns (m_ctxt); }
-  virtual unsigned int execute (function *)
+  opt_pass * clone () final override
+  {
+    return new pass_split_all_insns (m_ctxt);
+  }
+  unsigned int execute (function *) final override
     {
       split_all_insns ();
       return 0;
@@ -4440,13 +4446,13 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *)
+  bool gate (function *) final override
     {
       /* If optimizing, then go ahead and split insns now.  */
       return optimize > 0;
     }
 
-  virtual unsigned int execute (function *)
+  unsigned int execute (function *) final override
     {
       split_all_insns ();
       return 0;
@@ -4495,12 +4501,12 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *)
+  bool gate (function *) final override
     {
       return enable_split_before_sched2 ();
     }
 
-  virtual unsigned int execute (function *)
+  unsigned int execute (function *) final override
     {
       split_all_insns ();
       return 0;
@@ -4539,8 +4545,8 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *);
-  virtual unsigned int execute (function *)
+  bool gate (function *) final override;
+  unsigned int execute (function *) final override
     {
       split_all_insns ();
       return 0;
@@ -4598,7 +4604,7 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *)
+  bool gate (function *) final override
     {
       /* The placement of the splitting that we do for shorten_branches
 	 depends on whether regstack is used by the target or not.  */
@@ -4609,7 +4615,7 @@ public:
 #endif
     }
 
-  virtual unsigned int execute (function *)
+  unsigned int execute (function *) final override
     {
       return split_all_insns_noflow ();
     }
diff --git a/gcc/ree.cc b/gcc/ree.cc
index de4f18e8a4d..da64ef679b7 100644
--- a/gcc/ree.cc
+++ b/gcc/ree.cc
@@ -1403,8 +1403,11 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *) { return (optimize > 0 && flag_ree); }
-  virtual unsigned int execute (function *) { return rest_of_handle_ree (); }
+  bool gate (function *) final override { return (optimize > 0 && flag_ree); }
+  unsigned int execute (function *) final override
+  {
+    return rest_of_handle_ree ();
+  }
 
 }; // class pass_ree
 
diff --git a/gcc/reg-stack.cc b/gcc/reg-stack.cc
index 5afeadf8c49..fd032501ad9 100644
--- a/gcc/reg-stack.cc
+++ b/gcc/reg-stack.cc
@@ -3413,7 +3413,7 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *)
+  bool gate (function *) final override
     {
 #ifdef STACK_REGS
       return true;
@@ -3468,7 +3468,7 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual unsigned int execute (function *)
+  unsigned int execute (function *) final override
     {
       return rest_of_handle_stack_regs ();
     }
diff --git a/gcc/regcprop.cc b/gcc/regcprop.cc
index 1fdc36713cd..8fcf9d529dd 100644
--- a/gcc/regcprop.cc
+++ b/gcc/regcprop.cc
@@ -1293,12 +1293,12 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *)
+  bool gate (function *) final override
     {
       return (optimize > 0 && (flag_cprop_registers));
     }
 
-  virtual unsigned int execute (function *);
+  unsigned int execute (function *) final override;
 
 }; // class pass_cprop_hardreg
 
diff --git a/gcc/reginfo.cc b/gcc/reginfo.cc
index 2ab7bbb7353..705779d5c18 100644
--- a/gcc/reginfo.cc
+++ b/gcc/reginfo.cc
@@ -953,7 +953,7 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual unsigned int execute (function *) { return reginfo_init (); }
+  unsigned int execute (function *) final override { return reginfo_init (); }
 
 }; // class pass_reginfo_init
 
diff --git a/gcc/regrename.cc b/gcc/regrename.cc
index 10271e1b17d..021a822cb79 100644
--- a/gcc/regrename.cc
+++ b/gcc/regrename.cc
@@ -2013,12 +2013,15 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *)
+  bool gate (function *) final override
     {
       return (optimize > 0 && (flag_rename_registers));
     }
 
-  virtual unsigned int execute (function *) { return regrename_optimize (); }
+  unsigned int execute (function *) final override
+  {
+    return regrename_optimize ();
+  }
 
 }; // class pass_regrename
 
diff --git a/gcc/reorg.cc b/gcc/reorg.cc
index 7624f514906..07b2045986c 100644
--- a/gcc/reorg.cc
+++ b/gcc/reorg.cc
@@ -3866,8 +3866,8 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *);
-  virtual unsigned int execute (function *)
+  bool gate (function *) final override;
+  unsigned int execute (function *) final override
     {
       return rest_of_handle_delay_slots ();
     }
@@ -3917,12 +3917,12 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *)
+  bool gate (function *) final override
     {
       return targetm.machine_dependent_reorg != 0;
     }
 
-  virtual unsigned int execute (function *)
+  unsigned int execute (function *) final override
     {
       targetm.machine_dependent_reorg ();
       return 0;
diff --git a/gcc/sancov.cc b/gcc/sancov.cc
index 9c1025200b4..052fa4ef881 100644
--- a/gcc/sancov.cc
+++ b/gcc/sancov.cc
@@ -308,17 +308,17 @@ public:
 
   static const pass_data data;
   opt_pass *
-  clone ()
+  clone () final override
   {
     return new pass_sancov<O0> (m_ctxt);
   }
-  virtual bool
-  gate (function *fun)
+  bool
+  gate (function *fun) final override
   {
     return sanitize_coverage_p (fun->decl) && (!O0 || !optimize);
   }
-  virtual unsigned int
-  execute (function *fun)
+  unsigned int
+  execute (function *fun) final override
   {
     return sancov_pass (fun);
   }
diff --git a/gcc/sanopt.cc b/gcc/sanopt.cc
index 125e0c936e7..7aebc6f39dc 100644
--- a/gcc/sanopt.cc
+++ b/gcc/sanopt.cc
@@ -942,8 +942,8 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *) { return flag_sanitize; }
-  virtual unsigned int execute (function *);
+  bool gate (function *) final override { return flag_sanitize; }
+  unsigned int execute (function *) final override;
 
 }; // class pass_sanopt
 
diff --git a/gcc/sched-rgn.cc b/gcc/sched-rgn.cc
index a0dfdb7881f..0dc2a8f2851 100644
--- a/gcc/sched-rgn.cc
+++ b/gcc/sched-rgn.cc
@@ -3779,7 +3779,7 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *)
+  bool gate (function *) final override
     {
 #ifdef INSN_SCHEDULING
       return flag_live_range_shrinkage;
@@ -3788,7 +3788,7 @@ public:
 #endif
     }
 
-  virtual unsigned int execute (function *)
+  unsigned int execute (function *) final override
     {
       return rest_of_handle_live_range_shrinkage ();
     }
@@ -3826,8 +3826,11 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *);
-  virtual unsigned int execute (function *) { return rest_of_handle_sched (); }
+  bool gate (function *) final override;
+  unsigned int execute (function *) final override
+  {
+    return rest_of_handle_sched ();
+  }
 
 }; // class pass_sched
 
@@ -3872,8 +3875,8 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *);
-  virtual unsigned int execute (function *)
+  bool gate (function *) final override;
+  unsigned int execute (function *) final override
     {
       return rest_of_handle_sched2 ();
     }
@@ -3922,8 +3925,8 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *);
-  virtual unsigned int execute (function *)
+  bool gate (function *) final override;
+  unsigned int execute (function *) final override
     {
       return rest_of_handle_sched_fusion ();
     }
diff --git a/gcc/stack-ptr-mod.cc b/gcc/stack-ptr-mod.cc
index b14bef98c49..4ccbb1cace3 100644
--- a/gcc/stack-ptr-mod.cc
+++ b/gcc/stack-ptr-mod.cc
@@ -71,7 +71,7 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual unsigned int execute (function *);
+  unsigned int execute (function *) final override;
 
 }; // class pass_stack_ptr_mod
 
diff --git a/gcc/store-motion.cc b/gcc/store-motion.cc
index 0f708700a14..b61c0686844 100644
--- a/gcc/store-motion.cc
+++ b/gcc/store-motion.cc
@@ -1243,8 +1243,8 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *);
-  virtual unsigned int execute (function *)
+  bool gate (function *) final override;
+  unsigned int execute (function *) final override
     {
       return execute_rtl_store_motion ();
     }
diff --git a/gcc/tracer.cc b/gcc/tracer.cc
index 4d054fe8fc8..64517846dc4 100644
--- a/gcc/tracer.cc
+++ b/gcc/tracer.cc
@@ -424,12 +424,12 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *)
+  bool gate (function *) final override
     {
       return (optimize > 0 && flag_tracer && flag_reorder_blocks);
     }
 
-  virtual unsigned int execute (function *);
+  unsigned int execute (function *) final override;
 
 }; // class pass_tracer
 
diff --git a/gcc/trans-mem.cc b/gcc/trans-mem.cc
index ae2921f808e..131dce05476 100644
--- a/gcc/trans-mem.cc
+++ b/gcc/trans-mem.cc
@@ -864,8 +864,11 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *) { return flag_tm; }
-  virtual unsigned int execute (function *) { return diagnose_tm_blocks (); }
+  bool gate (function *) final override { return flag_tm; }
+  unsigned int execute (function *) final override
+  {
+    return diagnose_tm_blocks ();
+  }
 
 }; // class pass_diagnose_tm_blocks
 
@@ -1850,8 +1853,11 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *) { return flag_tm; }
-  virtual unsigned int execute (function *) { return execute_lower_tm (); }
+  bool gate (function *) final override { return flag_tm; }
+  unsigned int execute (function *) final override
+  {
+    return execute_lower_tm ();
+  }
 
 }; // class pass_lower_tm
 
@@ -2144,7 +2150,7 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *) { return gate_tm_init (); }
+  bool gate (function *) final override { return gate_tm_init (); }
 
 }; // class pass_tm_init
 
@@ -3162,7 +3168,10 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual unsigned int execute (function *) { return execute_tm_mark (); }
+  unsigned int execute (function *) final override
+  {
+    return execute_tm_mark ();
+  }
 
 }; // class pass_tm_mark
 
@@ -3324,7 +3333,7 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual unsigned int execute (function *);
+  unsigned int execute (function *) final override;
 
 }; // class pass_tm_edges
 
@@ -4085,8 +4094,11 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *) { return flag_tm && optimize > 0; }
-  virtual unsigned int execute (function *) { return execute_tm_memopt (); }
+  bool gate (function *) final override { return flag_tm && optimize > 0; }
+  unsigned int execute (function *) final override
+  {
+    return execute_tm_memopt ();
+  }
 
 }; // class pass_tm_memopt
 
@@ -5667,8 +5679,8 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *) { return flag_tm; }
-  virtual unsigned int execute (function *) { return ipa_tm_execute (); }
+  bool gate (function *) final override { return flag_tm; }
+  unsigned int execute (function *) final override { return ipa_tm_execute (); }
 
 }; // class pass_ipa_tm
 
diff --git a/gcc/tree-call-cdce.cc b/gcc/tree-call-cdce.cc
index 83991fe373e..feb61f362cf 100644
--- a/gcc/tree-call-cdce.cc
+++ b/gcc/tree-call-cdce.cc
@@ -1171,7 +1171,7 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *)
+  bool gate (function *) final override
     {
       /* The limit constants used in the implementation
 	 assume IEEE floating point format.  Other formats
@@ -1179,7 +1179,7 @@ public:
       return flag_tree_builtin_call_dce != 0;
     }
 
-  virtual unsigned int execute (function *);
+  unsigned int execute (function *) final override;
 
 }; // class pass_call_cdce
 
diff --git a/gcc/tree-cfg.cc b/gcc/tree-cfg.cc
index 19ba09facce..37e89adf10e 100644
--- a/gcc/tree-cfg.cc
+++ b/gcc/tree-cfg.cc
@@ -407,7 +407,10 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual unsigned int execute (function *) { return execute_build_cfg (); }
+  unsigned int execute (function *) final override
+  {
+    return execute_build_cfg ();
+  }
 
 }; // class pass_build_cfg
 
@@ -9200,9 +9203,15 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual unsigned int execute (function *) { return split_critical_edges (); }
+  unsigned int execute (function *)  final override
+  {
+    return split_critical_edges ();
+  }
 
-  opt_pass * clone () { return new pass_split_crit_edges (m_ctxt); }
+  opt_pass * clone () final override
+  {
+    return new pass_split_crit_edges (m_ctxt);
+  }
 }; // class pass_split_crit_edges
 
 } // anon namespace
@@ -9459,7 +9468,7 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual unsigned int execute (function *);
+  unsigned int execute (function *) final override;
 
 }; // class pass_warn_function_return
 
@@ -9665,8 +9674,8 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *) { return flag_warn_unused_result; }
-  virtual unsigned int execute (function *)
+  bool gate (function *)  final override { return flag_warn_unused_result; }
+  unsigned int execute (function *) final override
     {
       do_warn_unused_result (gimple_body (current_function_decl));
       return 0;
@@ -9875,8 +9884,11 @@ public:
   {}
 
   /* opt_pass methods: */
-  opt_pass * clone () { return new pass_fixup_cfg (m_ctxt); }
-  virtual unsigned int execute (function *) { return execute_fixup_cfg (); }
+  opt_pass * clone () final override { return new pass_fixup_cfg (m_ctxt); }
+  unsigned int execute (function *) final override
+  {
+    return execute_fixup_cfg ();
+  }
 
 }; // class pass_fixup_cfg
 
diff --git a/gcc/tree-cfgcleanup.cc b/gcc/tree-cfgcleanup.cc
index 893619eaaa4..a6d0bf2c40a 100644
--- a/gcc/tree-cfgcleanup.cc
+++ b/gcc/tree-cfgcleanup.cc
@@ -1406,8 +1406,8 @@ public:
   {}
 
   /* opt_pass methods: */
-  opt_pass * clone () { return new pass_merge_phi (m_ctxt); }
-  virtual unsigned int execute (function *);
+  opt_pass * clone () final override { return new pass_merge_phi (m_ctxt); }
+  unsigned int execute (function *) final override;
 
 }; // class pass_merge_phi
 
@@ -1584,7 +1584,7 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual unsigned int execute (function *)
+  unsigned int execute (function *) final override
     {
       return execute_cleanup_cfg_post_optimizing ();
     }
diff --git a/gcc/tree-complex.cc b/gcc/tree-complex.cc
index f722057bfec..61950a0f099 100644
--- a/gcc/tree-complex.cc
+++ b/gcc/tree-complex.cc
@@ -1915,8 +1915,11 @@ public:
   {}
 
   /* opt_pass methods: */
-  opt_pass * clone () { return new pass_lower_complex (m_ctxt); }
-  virtual unsigned int execute (function *) { return tree_lower_complex (); }
+  opt_pass * clone () final override { return new pass_lower_complex (m_ctxt); }
+  unsigned int execute (function *) final override
+  {
+    return tree_lower_complex ();
+  }
 
 }; // class pass_lower_complex
 
@@ -1952,14 +1955,17 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *fun)
+  bool gate (function *fun) final override
     {
       /* With errors, normal optimization passes are not run.  If we don't
 	 lower complex operations at all, rtl expansion will abort.  */
       return !(fun->curr_properties & PROP_gimple_lcx);
     }
 
-  virtual unsigned int execute (function *) { return tree_lower_complex (); }
+  unsigned int execute (function *) final override
+  {
+    return tree_lower_complex ();
+  }
 
 }; // class pass_lower_complex_O0
 
diff --git a/gcc/tree-eh.cc b/gcc/tree-eh.cc
index c37a5845343..076ecd3ec9a 100644
--- a/gcc/tree-eh.cc
+++ b/gcc/tree-eh.cc
@@ -2176,7 +2176,7 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual unsigned int execute (function *);
+  unsigned int execute (function *) final override;
 
 }; // class pass_lower_eh
 
@@ -3295,8 +3295,8 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *) { return flag_exceptions != 0; }
-  virtual unsigned int execute (function *)
+  bool gate (function *) final override { return flag_exceptions != 0; }
+  unsigned int execute (function *) final override
     {
       refactor_eh_r (gimple_body (current_function_decl));
       return 0;
@@ -3497,8 +3497,8 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *) { return flag_exceptions != 0; }
-  virtual unsigned int execute (function *);
+  bool gate (function *) final override { return flag_exceptions != 0; }
+  unsigned int execute (function *) final override;
 
 }; // class pass_lower_resx
 
@@ -3922,8 +3922,11 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *fun) { return fun->eh->region_tree != NULL; }
-  virtual unsigned int execute (function *);
+  bool gate (function *fun) final override
+  {
+    return fun->eh->region_tree != NULL;
+  }
+  unsigned int execute (function *) final override;
 
 }; // class pass_lower_eh_dispatch
 
@@ -4859,13 +4862,13 @@ public:
   {}
 
   /* opt_pass methods: */
-  opt_pass * clone () { return new pass_cleanup_eh (m_ctxt); }
-  virtual bool gate (function *fun)
+  opt_pass * clone () final override { return new pass_cleanup_eh (m_ctxt); }
+  bool gate (function *fun) final override
     {
       return fun->eh != NULL && fun->eh->region_tree != NULL;
     }
 
-  virtual unsigned int execute (function *);
+  unsigned int execute (function *) final override;
 
 }; // class pass_cleanup_eh
 
diff --git a/gcc/tree-emutls.cc b/gcc/tree-emutls.cc
index 5f68703822c..b5aa307f60d 100644
--- a/gcc/tree-emutls.cc
+++ b/gcc/tree-emutls.cc
@@ -838,13 +838,16 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *)
+  bool gate (function *) final override
     {
       /* If the target supports TLS natively, we need do nothing here.  */
       return !targetm.have_tls;
     }
 
-  virtual unsigned int execute (function *) { return ipa_lower_emutls (); }
+  unsigned int execute (function *) final override
+  {
+    return ipa_lower_emutls ();
+  }
 
 }; // class pass_ipa_lower_emutls
 
diff --git a/gcc/tree-if-conv.cc b/gcc/tree-if-conv.cc
index 4531ca58bdf..480fea0e7c2 100644
--- a/gcc/tree-if-conv.cc
+++ b/gcc/tree-if-conv.cc
@@ -3408,8 +3408,8 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *);
-  virtual unsigned int execute (function *);
+  bool gate (function *) final override;
+  unsigned int execute (function *) final override;
 
 }; // class pass_if_conversion
 
diff --git a/gcc/tree-into-ssa.cc b/gcc/tree-into-ssa.cc
index 22c2e5b7982..46df57ae0e1 100644
--- a/gcc/tree-into-ssa.cc
+++ b/gcc/tree-into-ssa.cc
@@ -2403,13 +2403,13 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *fun)
+  bool gate (function *fun) final override
     {
       /* Do nothing for funcions that was produced already in SSA form.  */
       return !(fun->curr_properties & PROP_ssa);
     }
 
-  virtual unsigned int execute (function *);
+  unsigned int execute (function *) final override;
 
 }; // class pass_build_ssa
 
diff --git a/gcc/tree-loop-distribution.cc b/gcc/tree-loop-distribution.cc
index db6e9096a86..ec44c450cae 100644
--- a/gcc/tree-loop-distribution.cc
+++ b/gcc/tree-loop-distribution.cc
@@ -3896,13 +3896,13 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *)
+  bool gate (function *) final override
     {
       return flag_tree_loop_distribution
 	|| flag_tree_loop_distribute_patterns;
     }
 
-  virtual unsigned int execute (function *);
+  unsigned int execute (function *) final override;
 
 }; // class pass_loop_distribution
 
diff --git a/gcc/tree-nrv.cc b/gcc/tree-nrv.cc
index b96d5b86f27..1faa481a8c9 100644
--- a/gcc/tree-nrv.cc
+++ b/gcc/tree-nrv.cc
@@ -125,9 +125,9 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *) { return optimize > 0; }
+  bool gate (function *) final override { return optimize > 0; }
 
-  virtual unsigned int execute (function *);
+  unsigned int execute (function *) final override;
 
 }; // class pass_nrv
 
@@ -344,7 +344,7 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual unsigned int execute (function *);
+  unsigned int execute (function *) final override;
 
 }; // class pass_return_slot
 
diff --git a/gcc/tree-object-size.cc b/gcc/tree-object-size.cc
index 5ca87ae3504..bc3d7dd9bfa 100644
--- a/gcc/tree-object-size.cc
+++ b/gcc/tree-object-size.cc
@@ -2122,8 +2122,8 @@ public:
   {}
 
   /* opt_pass methods: */
-  opt_pass * clone () { return new pass_object_sizes (m_ctxt); }
-  virtual unsigned int execute (function *fun)
+  opt_pass * clone () final override { return new pass_object_sizes (m_ctxt); }
+  unsigned int execute (function *fun) final override
   {
     return object_sizes_execute (fun, false);
   }
@@ -2162,7 +2162,7 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual unsigned int execute (function *fun)
+  unsigned int execute (function *fun) final override
   {
     return object_sizes_execute (fun, true);
   }
diff --git a/gcc/tree-parloops.cc b/gcc/tree-parloops.cc
index da1069683a3..2c3ef436ab7 100644
--- a/gcc/tree-parloops.cc
+++ b/gcc/tree-parloops.cc
@@ -4173,16 +4173,19 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *)
+  bool gate (function *) final override
   {
     if (oacc_kernels_p)
       return flag_openacc;
     else
       return flag_tree_parallelize_loops > 1;
   }
-  virtual unsigned int execute (function *);
-  opt_pass * clone () { return new pass_parallelize_loops (m_ctxt); }
-  void set_pass_param (unsigned int n, bool param)
+  unsigned int execute (function *) final override;
+  opt_pass * clone () final override
+  {
+    return new pass_parallelize_loops (m_ctxt);
+  }
+  void set_pass_param (unsigned int n, bool param) final override
     {
       gcc_assert (n == 0);
       oacc_kernels_p = param;
diff --git a/gcc/tree-predcom.cc b/gcc/tree-predcom.cc
index fb457250bbd..5d923fba170 100644
--- a/gcc/tree-predcom.cc
+++ b/gcc/tree-predcom.cc
@@ -3514,8 +3514,8 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool
-  gate (function *)
+  bool
+  gate (function *) final override
   {
     if (flag_predictive_commoning != 0)
       return true;
@@ -3529,8 +3529,8 @@ public:
     return false;
   }
 
-  virtual unsigned int
-  execute (function *fun)
+  unsigned int
+  execute (function *fun) final override
   {
     bool allow_unroll_p = flag_predictive_commoning != 0;
     return run_tree_predictive_commoning (fun, allow_unroll_p);
diff --git a/gcc/tree-profile.cc b/gcc/tree-profile.cc
index 97aab8801d0..2beb49241f2 100644
--- a/gcc/tree-profile.cc
+++ b/gcc/tree-profile.cc
@@ -884,8 +884,8 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *);
-  virtual unsigned int execute (function *) { return tree_profiling (); }
+  bool gate (function *) final override;
+  unsigned int execute (function *) final override { return tree_profiling (); }
 
 }; // class pass_ipa_tree_profile
 
diff --git a/gcc/tree-sra.cc b/gcc/tree-sra.cc
index 081c51b58a4..461c8e0b0f4 100644
--- a/gcc/tree-sra.cc
+++ b/gcc/tree-sra.cc
@@ -4743,8 +4743,11 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *) { return gate_intra_sra (); }
-  virtual unsigned int execute (function *) { return early_intra_sra (); }
+  bool gate (function *) final override { return gate_intra_sra (); }
+  unsigned int execute (function *) final override
+  {
+    return early_intra_sra ();
+  }
 
 }; // class pass_sra_early
 
@@ -4779,8 +4782,8 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *) { return gate_intra_sra (); }
-  virtual unsigned int execute (function *) { return late_intra_sra (); }
+  bool gate (function *) final override { return gate_intra_sra (); }
+  unsigned int execute (function *) final override { return late_intra_sra (); }
 
 }; // class pass_sra
 
diff --git a/gcc/tree-ssa-ccp.cc b/gcc/tree-ssa-ccp.cc
index 81c97676625..579a966cc9b 100644
--- a/gcc/tree-ssa-ccp.cc
+++ b/gcc/tree-ssa-ccp.cc
@@ -2994,14 +2994,17 @@ public:
   {}
 
   /* opt_pass methods: */
-  opt_pass * clone () { return new pass_ccp (m_ctxt); }
-  void set_pass_param (unsigned int n, bool param)
+  opt_pass * clone () final override { return new pass_ccp (m_ctxt); }
+  void set_pass_param (unsigned int n, bool param) final override
     {
       gcc_assert (n == 0);
       nonzero_p = param;
     }
-  virtual bool gate (function *) { return flag_tree_ccp != 0; }
-  virtual unsigned int execute (function *) { return do_ssa_ccp (nonzero_p); }
+  bool gate (function *) final override { return flag_tree_ccp != 0; }
+  unsigned int execute (function *) final override
+  {
+    return do_ssa_ccp (nonzero_p);
+  }
 
  private:
   /* Determines whether the pass instance records nonzero bits.  */
@@ -4199,8 +4202,8 @@ public:
   {}
 
   /* opt_pass methods: */
-  opt_pass * clone () { return new pass_fold_builtins (m_ctxt); }
-  virtual unsigned int execute (function *);
+  opt_pass * clone () final override { return new pass_fold_builtins (m_ctxt); }
+  unsigned int execute (function *) final override;
 
 }; // class pass_fold_builtins
 
@@ -4550,9 +4553,9 @@ public:
   {}
 
   /* opt_pass methods: */
-  opt_pass * clone () { return new pass_post_ipa_warn (m_ctxt); }
-  virtual bool gate (function *) { return warn_nonnull != 0; }
-  virtual unsigned int execute (function *);
+  opt_pass * clone () final override { return new pass_post_ipa_warn (m_ctxt); }
+  bool gate (function *) final override { return warn_nonnull != 0; }
+  unsigned int execute (function *) final override;
 
 }; // class pass_fold_builtins
 
diff --git a/gcc/tree-ssa-copy.cc b/gcc/tree-ssa-copy.cc
index 050a6d11434..782ceb500cc 100644
--- a/gcc/tree-ssa-copy.cc
+++ b/gcc/tree-ssa-copy.cc
@@ -642,9 +642,12 @@ public:
   {}
 
   /* opt_pass methods: */
-  opt_pass * clone () { return new pass_copy_prop (m_ctxt); }
-  virtual bool gate (function *) { return flag_tree_copy_prop != 0; }
-  virtual unsigned int execute (function *) { return execute_copy_prop (); }
+  opt_pass * clone () final override { return new pass_copy_prop (m_ctxt); }
+  bool gate (function *) final override { return flag_tree_copy_prop != 0; }
+  unsigned int execute (function *) final override
+  {
+    return execute_copy_prop ();
+  }
 
 }; // class pass_copy_prop
 
diff --git a/gcc/tree-ssa-dce.cc b/gcc/tree-ssa-dce.cc
index a6b284018d4..5df64922594 100644
--- a/gcc/tree-ssa-dce.cc
+++ b/gcc/tree-ssa-dce.cc
@@ -1974,9 +1974,9 @@ public:
   {}
 
   /* opt_pass methods: */
-  opt_pass * clone () { return new pass_dce (m_ctxt); }
-  virtual bool gate (function *) { return flag_tree_dce != 0; }
-  virtual unsigned int execute (function *) { return tree_ssa_dce (); }
+  opt_pass * clone () final override { return new pass_dce (m_ctxt); }
+  bool gate (function *) final override { return flag_tree_dce != 0; }
+  unsigned int execute (function *) final override { return tree_ssa_dce (); }
 
 }; // class pass_dce
 
@@ -2011,14 +2011,14 @@ public:
   {}
 
   /* opt_pass methods: */
-  opt_pass * clone () { return new pass_cd_dce (m_ctxt); }
-  void set_pass_param (unsigned n, bool param)
+  opt_pass * clone () final override { return new pass_cd_dce (m_ctxt); }
+  void set_pass_param (unsigned n, bool param) final override
     {
       gcc_assert (n == 0);
       update_address_taken_p = param;
     }
-  virtual bool gate (function *) { return flag_tree_dce != 0; }
-  virtual unsigned int execute (function *)
+  bool gate (function *) final override { return flag_tree_dce != 0; }
+  unsigned int execute (function *) final override
     {
       return (tree_ssa_cd_dce ()
 	      | (update_address_taken_p ? TODO_update_address_taken : 0));
diff --git a/gcc/tree-ssa-dom.cc b/gcc/tree-ssa-dom.cc
index 9a843217553..97e17ca68e4 100644
--- a/gcc/tree-ssa-dom.cc
+++ b/gcc/tree-ssa-dom.cc
@@ -793,14 +793,14 @@ public:
   {}
 
   /* opt_pass methods: */
-  opt_pass * clone () { return new pass_dominator (m_ctxt); }
-  void set_pass_param (unsigned int n, bool param)
+  opt_pass * clone () final override { return new pass_dominator (m_ctxt); }
+  void set_pass_param (unsigned int n, bool param) final override
     {
       gcc_assert (n == 0);
       may_peel_loop_headers_p = param;
     }
-  virtual bool gate (function *) { return flag_tree_dom != 0; }
-  virtual unsigned int execute (function *);
+  bool gate (function *) final override { return flag_tree_dom != 0; }
+  unsigned int execute (function *) final override;
 
  private:
   /* This flag is used to prevent loops from being peeled repeatedly in jump
diff --git a/gcc/tree-ssa-dse.cc b/gcc/tree-ssa-dse.cc
index 881a2d0f98d..1c1fdb7e75b 100644
--- a/gcc/tree-ssa-dse.cc
+++ b/gcc/tree-ssa-dse.cc
@@ -1455,9 +1455,9 @@ public:
   {}
 
   /* opt_pass methods: */
-  opt_pass * clone () { return new pass_dse (m_ctxt); }
-  virtual bool gate (function *) { return flag_tree_dse != 0; }
-  virtual unsigned int execute (function *);
+  opt_pass * clone () final override { return new pass_dse (m_ctxt); }
+  bool gate (function *) final override { return flag_tree_dse != 0; }
+  unsigned int execute (function *) final override;
 
 }; // class pass_dse
 
diff --git a/gcc/tree-ssa-forwprop.cc b/gcc/tree-ssa-forwprop.cc
index 0917202b74c..6f09642172d 100644
--- a/gcc/tree-ssa-forwprop.cc
+++ b/gcc/tree-ssa-forwprop.cc
@@ -3330,9 +3330,9 @@ public:
   {}
 
   /* opt_pass methods: */
-  opt_pass * clone () { return new pass_forwprop (m_ctxt); }
-  virtual bool gate (function *) { return flag_tree_forwprop; }
-  virtual unsigned int execute (function *);
+  opt_pass * clone () final override { return new pass_forwprop (m_ctxt); }
+  bool gate (function *) final override { return flag_tree_forwprop; }
+  unsigned int execute (function *) final override;
 
 }; // class pass_forwprop
 
diff --git a/gcc/tree-ssa-ifcombine.cc b/gcc/tree-ssa-ifcombine.cc
index 88a9f062dcd..80c41c45489 100644
--- a/gcc/tree-ssa-ifcombine.cc
+++ b/gcc/tree-ssa-ifcombine.cc
@@ -829,7 +829,7 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual unsigned int execute (function *);
+  unsigned int execute (function *) final override;
 
 }; // class pass_tree_ifcombine
 
diff --git a/gcc/tree-ssa-loop-ch.cc b/gcc/tree-ssa-loop-ch.cc
index 2f5a390404c..9ab63d1fa0c 100644
--- a/gcc/tree-ssa-loop-ch.cc
+++ b/gcc/tree-ssa-loop-ch.cc
@@ -311,12 +311,12 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *) { return flag_tree_ch != 0; }
+  bool gate (function *) final override { return flag_tree_ch != 0; }
   
   /* Initialize and finalize loop structures, copying headers inbetween.  */
-  virtual unsigned int execute (function *);
+  unsigned int execute (function *) final override;
 
-  opt_pass * clone () { return new pass_ch (m_ctxt); }
+  opt_pass * clone () final override { return new pass_ch (m_ctxt); }
 
 protected:
   /* ch_base method: */
@@ -347,14 +347,14 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *fun)
+  bool gate (function *fun) final override
   {
     return flag_tree_ch != 0
 	   && (flag_tree_loop_vectorize != 0 || fun->has_force_vectorize_loops);
   }
   
   /* Just copy headers, no initialization/finalization of loop structures.  */
-  virtual unsigned int execute (function *);
+  unsigned int execute (function *) final override;
 
 protected:
   /* ch_base method: */
diff --git a/gcc/tree-ssa-loop-im.cc b/gcc/tree-ssa-loop-im.cc
index 6d9316eed1f..c0893f1927c 100644
--- a/gcc/tree-ssa-loop-im.cc
+++ b/gcc/tree-ssa-loop-im.cc
@@ -3597,9 +3597,9 @@ public:
   {}
 
   /* opt_pass methods: */
-  opt_pass * clone () { return new pass_lim (m_ctxt); }
-  virtual bool gate (function *) { return flag_tree_loop_im != 0; }
-  virtual unsigned int execute (function *);
+  opt_pass * clone () final override { return new pass_lim (m_ctxt); }
+  bool gate (function *) final override { return flag_tree_loop_im != 0; }
+  unsigned int execute (function *) final override;
 
 }; // class pass_lim
 
diff --git a/gcc/tree-ssa-loop-ivcanon.cc b/gcc/tree-ssa-loop-ivcanon.cc
index 2ee00a3f843..e52397235a1 100644
--- a/gcc/tree-ssa-loop-ivcanon.cc
+++ b/gcc/tree-ssa-loop-ivcanon.cc
@@ -1539,8 +1539,8 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *) { return flag_tree_loop_ivcanon != 0; }
-  virtual unsigned int execute (function *fun);
+  bool gate (function *) final override { return flag_tree_loop_ivcanon != 0; }
+  unsigned int execute (function *fun) final override;
 
 }; // class pass_iv_canon
 
@@ -1586,7 +1586,7 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual unsigned int execute (function *);
+  unsigned int execute (function *) final override;
 
 }; // class pass_complete_unroll
 
@@ -1644,8 +1644,8 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *) { return optimize >= 2; }
-  virtual unsigned int execute (function *);
+  bool gate (function *) final override { return optimize >= 2; }
+  unsigned int execute (function *) final override;
 
 }; // class pass_complete_unrolli
 
diff --git a/gcc/tree-ssa-loop-prefetch.cc b/gcc/tree-ssa-loop-prefetch.cc
index aebd7c9206f..8f190ae469b 100644
--- a/gcc/tree-ssa-loop-prefetch.cc
+++ b/gcc/tree-ssa-loop-prefetch.cc
@@ -2069,8 +2069,11 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *) { return flag_prefetch_loop_arrays > 0; }
-  virtual unsigned int execute (function *);
+  bool gate (function *) final override
+  {
+    return flag_prefetch_loop_arrays > 0;
+  }
+  unsigned int execute (function *) final override;
 
 }; // class pass_loop_prefetch
 
diff --git a/gcc/tree-ssa-loop-split.cc b/gcc/tree-ssa-loop-split.cc
index b93ee4c8769..d61bad5ba47 100644
--- a/gcc/tree-ssa-loop-split.cc
+++ b/gcc/tree-ssa-loop-split.cc
@@ -1724,8 +1724,8 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *) { return flag_split_loops != 0; }
-  virtual unsigned int execute (function *);
+  bool gate (function *) final override { return flag_split_loops != 0; }
+  unsigned int execute (function *) final override;
 
 }; // class pass_loop_split
 
diff --git a/gcc/tree-ssa-loop-unswitch.cc b/gcc/tree-ssa-loop-unswitch.cc
index 2927f308234..3b6486f305a 100644
--- a/gcc/tree-ssa-loop-unswitch.cc
+++ b/gcc/tree-ssa-loop-unswitch.cc
@@ -1035,8 +1035,8 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *) { return flag_unswitch_loops != 0; }
-  virtual unsigned int execute (function *);
+  bool gate (function *) final override { return flag_unswitch_loops != 0; }
+  unsigned int execute (function *) final override;
 
 }; // class pass_tree_unswitch
 
diff --git a/gcc/tree-ssa-loop.cc b/gcc/tree-ssa-loop.cc
index 73aa46627b4..1c058b08c2f 100644
--- a/gcc/tree-ssa-loop.cc
+++ b/gcc/tree-ssa-loop.cc
@@ -67,9 +67,9 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *) { return flag_tree_loop_optimize; }
+  bool gate (function *) final override { return flag_tree_loop_optimize; }
 
-  virtual unsigned int execute (function *fn);
+  unsigned int execute (function *fn) final override;
 }; // class pass_fix_loops
 
 unsigned int
@@ -134,7 +134,7 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *fn) { return gate_loop (fn); }
+  bool gate (function *fn) final override { return gate_loop (fn); }
 
 }; // class pass_tree_loop
 
@@ -189,7 +189,7 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *fn) { return gate_oacc_kernels (fn); }
+  bool gate (function *fn) final override { return gate_oacc_kernels (fn); }
 
 }; // class pass_oacc_kernels
 
@@ -226,7 +226,7 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *)
+  bool gate (function *) final override
   {
     return (optimize
 	    && flag_openacc
@@ -303,7 +303,7 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *fn) { return !gate_loop (fn); }
+  bool gate (function *fn) final override { return !gate_loop (fn); }
 
 }; // class pass_tree_no_loop
 
@@ -341,7 +341,7 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual unsigned int execute (function *);
+  unsigned int execute (function *) final override;
 
 }; // class pass_tree_loop_init
 
@@ -395,8 +395,8 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *) { return flag_tree_scev_cprop; }
-  virtual unsigned int execute (function *);
+  bool gate (function *) final override { return flag_tree_scev_cprop; }
+  unsigned int execute (function *) final override;
 
 }; // class pass_scev_cprop
 
@@ -446,8 +446,8 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *) { return flag_ivopts != 0; }
-  virtual unsigned int execute (function *);
+  bool gate (function *) final override { return flag_ivopts != 0; }
+  unsigned int execute (function *) final override;
 
 }; // class pass_iv_optimize
 
@@ -503,7 +503,10 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual unsigned int execute (function *) { return tree_ssa_loop_done (); }
+  unsigned int execute (function *) final override
+  {
+    return tree_ssa_loop_done ();
+  }
 
 }; // class pass_tree_loop_done
 
diff --git a/gcc/tree-ssa-math-opts.cc b/gcc/tree-ssa-math-opts.cc
index ce1df01f629..fe9f37b4cd4 100644
--- a/gcc/tree-ssa-math-opts.cc
+++ b/gcc/tree-ssa-math-opts.cc
@@ -920,8 +920,11 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *) { return optimize && flag_reciprocal_math; }
-  virtual unsigned int execute (function *);
+  bool gate (function *) final override
+  {
+    return optimize && flag_reciprocal_math;
+  }
+  unsigned int execute (function *) final override;
 
 }; // class pass_cse_reciprocals
 
@@ -2249,14 +2252,14 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *)
+  bool gate (function *) final override
     {
       /* We no longer require either sincos or cexp, since powi expansion
 	 piggybacks on this pass.  */
       return optimize;
     }
 
-  virtual unsigned int execute (function *);
+  unsigned int execute (function *) final override;
 
 }; // class pass_cse_sincos
 
@@ -4892,12 +4895,12 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *)
+  bool gate (function *) final override
     {
       return flag_expensive_optimizations && optimize;
     }
 
-  virtual unsigned int execute (function *);
+  unsigned int execute (function *) final override;
 
 }; // class pass_optimize_widening_mul
 
diff --git a/gcc/tree-ssa-phiopt.cc b/gcc/tree-ssa-phiopt.cc
index 8c9c46d41f1..162ca7098cd 100644
--- a/gcc/tree-ssa-phiopt.cc
+++ b/gcc/tree-ssa-phiopt.cc
@@ -3960,14 +3960,14 @@ public:
   {}
 
   /* opt_pass methods: */
-  opt_pass * clone () { return new pass_phiopt (m_ctxt); }
-  void set_pass_param (unsigned n, bool param)
+  opt_pass * clone () final override { return new pass_phiopt (m_ctxt); }
+  void set_pass_param (unsigned n, bool param) final override
     {
       gcc_assert (n == 0);
       early_p = param;
     }
-  virtual bool gate (function *) { return flag_ssa_phiopt; }
-  virtual unsigned int execute (function *)
+  bool gate (function *) final override { return flag_ssa_phiopt; }
+  unsigned int execute (function *) final override
     {
       return tree_ssa_phiopt_worker (false,
 				     !early_p ? gate_hoist_loads () : false,
@@ -4009,8 +4009,11 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *) { return flag_tree_cselim; }
-  virtual unsigned int execute (function *) { return tree_ssa_cs_elim (); }
+  bool gate (function *) final override { return flag_tree_cselim; }
+  unsigned int execute (function *) final override
+  {
+    return tree_ssa_cs_elim ();
+  }
 
 }; // class pass_cselim
 
diff --git a/gcc/tree-ssa-phiprop.cc b/gcc/tree-ssa-phiprop.cc
index 7bbfc8c002a..965f1d1c4eb 100644
--- a/gcc/tree-ssa-phiprop.cc
+++ b/gcc/tree-ssa-phiprop.cc
@@ -476,8 +476,8 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *) { return flag_tree_phiprop; }
-  virtual unsigned int execute (function *);
+  bool gate (function *) final override { return flag_tree_phiprop; }
+  unsigned int execute (function *) final override;
 
 }; // class pass_phiprop
 
diff --git a/gcc/tree-ssa-pre.cc b/gcc/tree-ssa-pre.cc
index 09a5e2055ca..e029bd36da3 100644
--- a/gcc/tree-ssa-pre.cc
+++ b/gcc/tree-ssa-pre.cc
@@ -4339,9 +4339,9 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *)
+  bool gate (function *) final override
     { return flag_tree_pre != 0 || flag_code_hoisting != 0; }
-  virtual unsigned int execute (function *);
+  unsigned int execute (function *) final override;
 
 }; // class pass_pre
 
diff --git a/gcc/tree-ssa-reassoc.cc b/gcc/tree-ssa-reassoc.cc
index 406523b5d2f..e13e2cb308d 100644
--- a/gcc/tree-ssa-reassoc.cc
+++ b/gcc/tree-ssa-reassoc.cc
@@ -7132,15 +7132,15 @@ public:
   {}
 
   /* opt_pass methods: */
-  opt_pass * clone () { return new pass_reassoc (m_ctxt); }
-  void set_pass_param (unsigned int n, bool param)
+  opt_pass * clone () final override { return new pass_reassoc (m_ctxt); }
+  void set_pass_param (unsigned int n, bool param) final override
     {
       gcc_assert (n == 0);
       insert_powi_p = param;
       bias_loop_carried_phi_ranks_p = !param;
     }
-  virtual bool gate (function *) { return flag_tree_reassoc != 0; }
-  virtual unsigned int execute (function *)
+  bool gate (function *) final override { return flag_tree_reassoc != 0; }
+  unsigned int execute (function *) final override
   {
     return execute_reassoc (insert_powi_p, bias_loop_carried_phi_ranks_p);
   }
diff --git a/gcc/tree-ssa-sccvn.cc b/gcc/tree-ssa-sccvn.cc
index ed68557f0b2..18392e031b8 100644
--- a/gcc/tree-ssa-sccvn.cc
+++ b/gcc/tree-ssa-sccvn.cc
@@ -8295,17 +8295,17 @@ public:
   {}
 
   /* opt_pass methods: */
-  opt_pass * clone () { return new pass_fre (m_ctxt); }
-  void set_pass_param (unsigned int n, bool param)
+  opt_pass * clone () final override { return new pass_fre (m_ctxt); }
+  void set_pass_param (unsigned int n, bool param) final override
     {
       gcc_assert (n == 0);
       may_iterate = param;
     }
-  virtual bool gate (function *)
+  bool gate (function *) final override
     {
       return flag_tree_fre != 0 && (may_iterate || optimize > 1);
     }
-  virtual unsigned int execute (function *);
+  unsigned int execute (function *) final override;
 
 private:
   bool may_iterate;
diff --git a/gcc/tree-ssa-sink.cc b/gcc/tree-ssa-sink.cc
index 8ce4403ddc8..7f653a988f4 100644
--- a/gcc/tree-ssa-sink.cc
+++ b/gcc/tree-ssa-sink.cc
@@ -829,10 +829,10 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *) { return flag_tree_sink != 0; }
-  virtual unsigned int execute (function *);
-  opt_pass *clone (void) { return new pass_sink_code (m_ctxt); }
-  void set_pass_param (unsigned n, bool param)
+  bool gate (function *) final override { return flag_tree_sink != 0; }
+  unsigned int execute (function *) final override;
+  opt_pass *clone (void) final override { return new pass_sink_code (m_ctxt); }
+  void set_pass_param (unsigned n, bool param) final override
     {
       gcc_assert (n == 0);
       unsplit_edges = param;
diff --git a/gcc/tree-ssa-strlen.cc b/gcc/tree-ssa-strlen.cc
index 1d4c0f78fbf..2cceba6f7af 100644
--- a/gcc/tree-ssa-strlen.cc
+++ b/gcc/tree-ssa-strlen.cc
@@ -5962,8 +5962,8 @@ public:
     : gimple_opt_pass (pass_data_warn_printf, ctxt)
   {}
 
-  virtual bool gate (function *);
-  virtual unsigned int execute (function *fun)
+  bool gate (function *) final override;
+  unsigned int execute (function *fun) final override
   {
     return printf_strlen_execute (fun, true);
   }
@@ -5999,10 +5999,10 @@ public:
     : gimple_opt_pass (pass_data_strlen, ctxt)
   {}
 
-  opt_pass * clone () { return new pass_strlen (m_ctxt); }
+  opt_pass * clone () final override { return new pass_strlen (m_ctxt); }
 
-  virtual bool gate (function *);
-  virtual unsigned int execute (function *fun)
+  bool gate (function *) final override;
+  unsigned int execute (function *fun) final override
   {
     return printf_strlen_execute (fun, false);
   }
diff --git a/gcc/tree-ssa-structalias.cc b/gcc/tree-ssa-structalias.cc
index 581bdcf5652..dcf13d939bd 100644
--- a/gcc/tree-ssa-structalias.cc
+++ b/gcc/tree-ssa-structalias.cc
@@ -8085,7 +8085,7 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *) { return flag_tree_pta; }
+  bool gate (function *) final override { return flag_tree_pta; }
 
 }; // class pass_build_alias
 
@@ -8123,7 +8123,7 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *) { return flag_tree_pta; }
+  bool gate (function *) final override { return flag_tree_pta; }
 
 }; // class pass_build_ealias
 
@@ -8737,7 +8737,7 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *)
+  bool gate (function *) final override
     {
       return (optimize
 	      && flag_ipa_pta
@@ -8745,9 +8745,12 @@ public:
 	      && !seen_error ());
     }
 
-  opt_pass * clone () { return new pass_ipa_pta (m_ctxt); }
+  opt_pass * clone () final override { return new pass_ipa_pta (m_ctxt); }
 
-  virtual unsigned int execute (function *) { return ipa_pta_execute (); }
+  unsigned int execute (function *) final override
+  {
+    return ipa_pta_execute ();
+  }
 
 }; // class pass_ipa_pta
 
diff --git a/gcc/tree-ssa-uncprop.cc b/gcc/tree-ssa-uncprop.cc
index aea7d69584f..510f8319d8c 100644
--- a/gcc/tree-ssa-uncprop.cc
+++ b/gcc/tree-ssa-uncprop.cc
@@ -453,9 +453,9 @@ public:
   {}
 
   /* opt_pass methods: */
-  opt_pass * clone () { return new pass_uncprop (m_ctxt); }
-  virtual bool gate (function *) { return flag_tree_dom != 0; }
-  virtual unsigned int execute (function *);
+  opt_pass * clone () final override { return new pass_uncprop (m_ctxt); }
+  bool gate (function *) final override { return flag_tree_dom != 0; }
+  unsigned int execute (function *) final override;
 
 }; // class pass_uncprop
 
diff --git a/gcc/tree-ssa-uninit.cc b/gcc/tree-ssa-uninit.cc
index b48fcf1a8ba..087f0dc965d 100644
--- a/gcc/tree-ssa-uninit.cc
+++ b/gcc/tree-ssa-uninit.cc
@@ -1317,9 +1317,12 @@ public:
   {}
 
   /* opt_pass methods: */
-  opt_pass *clone () { return new pass_late_warn_uninitialized (m_ctxt); }
-  virtual bool gate (function *) { return gate_warn_uninitialized (); }
-  virtual unsigned int execute (function *);
+  opt_pass *clone () final override
+  {
+    return new pass_late_warn_uninitialized (m_ctxt);
+  }
+  bool gate (function *) final override { return gate_warn_uninitialized (); }
+  unsigned int execute (function *) final override;
 
 }; // class pass_late_warn_uninitialized
 
@@ -1459,8 +1462,8 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *) { return gate_warn_uninitialized (); }
-  virtual unsigned int execute (function *fun)
+  bool gate (function *) final override { return gate_warn_uninitialized (); }
+  unsigned int execute (function *fun) final override
   {
     return execute_early_warn_uninitialized (fun);
   }
diff --git a/gcc/tree-ssanames.cc b/gcc/tree-ssanames.cc
index 05536cd2f74..bc22ece636a 100644
--- a/gcc/tree-ssanames.cc
+++ b/gcc/tree-ssanames.cc
@@ -920,7 +920,7 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual unsigned int execute (function *);
+  unsigned int execute (function *) final override;
 
 }; // class pass_release_ssa_names
 
diff --git a/gcc/tree-stdarg.cc b/gcc/tree-stdarg.cc
index 9038cd43aaa..ed4c8d8c775 100644
--- a/gcc/tree-stdarg.cc
+++ b/gcc/tree-stdarg.cc
@@ -1126,7 +1126,7 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *)
+  bool gate (function *) final override
     {
       /* Always run this pass, in order to expand va_arg internal_fns.  We
 	 also need to do that if fun->stdarg == 0, because a va_arg may also
@@ -1135,7 +1135,7 @@ public:
       return true;
     }
 
-  virtual unsigned int execute (function *);
+  unsigned int execute (function *) final override;
 
 }; // class pass_stdarg
 
@@ -1185,12 +1185,12 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *)
+  bool gate (function *) final override
     {
       return (cfun->curr_properties & PROP_gimple_lva) == 0;
     }
 
-  virtual unsigned int execute (function *);
+  unsigned int execute (function *) final override;
 
 }; // class pass_lower_vaarg
 
diff --git a/gcc/tree-switch-conversion.cc b/gcc/tree-switch-conversion.cc
index 50a17927f39..17a31f7a63c 100644
--- a/gcc/tree-switch-conversion.cc
+++ b/gcc/tree-switch-conversion.cc
@@ -2428,8 +2428,11 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *) { return flag_tree_switch_conversion != 0; }
-  virtual unsigned int execute (function *);
+  bool gate (function *) final override
+  {
+    return flag_tree_switch_conversion != 0;
+  }
+  unsigned int execute (function *) final override;
 
 }; // class pass_convert_switch
 
@@ -2507,18 +2510,18 @@ public:
 
   static const pass_data data;
   opt_pass *
-  clone ()
+  clone () final override
   {
     return new pass_lower_switch<O0> (m_ctxt);
   }
 
-  virtual bool
-  gate (function *)
+  bool
+  gate (function *) final override
   {
     return !O0 || !optimize;
   }
 
-  virtual unsigned int execute (function *fun);
+  unsigned int execute (function *fun) final override;
 }; // class pass_lower_switch
 
 template <bool O0>
diff --git a/gcc/tree-tailcall.cc b/gcc/tree-tailcall.cc
index 5a3466e5d53..6745d57580b 100644
--- a/gcc/tree-tailcall.cc
+++ b/gcc/tree-tailcall.cc
@@ -1261,9 +1261,12 @@ public:
   {}
 
   /* opt_pass methods: */
-  opt_pass * clone () { return new pass_tail_recursion (m_ctxt); }
-  virtual bool gate (function *) { return gate_tail_calls (); }
-  virtual unsigned int execute (function *)
+  opt_pass * clone () final override
+  {
+    return new pass_tail_recursion (m_ctxt);
+  }
+  bool gate (function *) final override { return gate_tail_calls (); }
+  unsigned int execute (function *) final override
     {
       return tree_optimize_tail_calls_1 (false);
     }
@@ -1301,8 +1304,11 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *) { return gate_tail_calls (); }
-  virtual unsigned int execute (function *) { return execute_tail_calls (); }
+  bool gate (function *) final override { return gate_tail_calls (); }
+  unsigned int execute (function *) final override
+  {
+    return execute_tail_calls ();
+  }
 
 }; // class pass_tail_calls
 
diff --git a/gcc/tree-vect-generic.cc b/gcc/tree-vect-generic.cc
index d99e3207fbe..d974fd1b7fe 100644
--- a/gcc/tree-vect-generic.cc
+++ b/gcc/tree-vect-generic.cc
@@ -2415,12 +2415,12 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *fun)
+  bool gate (function *fun) final override
     {
       return !(fun->curr_properties & PROP_gimple_lvec);
     }
 
-  virtual unsigned int execute (function *)
+  unsigned int execute (function *) final override
     {
       return expand_vector_operations ();
     }
@@ -2459,8 +2459,11 @@ public:
   {}
 
   /* opt_pass methods: */
-  opt_pass * clone () { return new pass_lower_vector_ssa (m_ctxt); }
-  virtual unsigned int execute (function *)
+  opt_pass * clone () final override
+  {
+    return new pass_lower_vector_ssa (m_ctxt);
+  }
+  unsigned int execute (function *) final override
     {
       return expand_vector_operations ();
     }
diff --git a/gcc/tree-vectorizer.cc b/gcc/tree-vectorizer.cc
index a63fa391273..53dc4520963 100644
--- a/gcc/tree-vectorizer.cc
+++ b/gcc/tree-vectorizer.cc
@@ -1193,12 +1193,12 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *fun)
+  bool gate (function *fun) final override
     {
       return flag_tree_loop_vectorize || fun->has_force_vectorize_loops;
     }
 
-  virtual unsigned int execute (function *);
+  unsigned int execute (function *) final override;
 
 }; // class pass_vectorize
 
@@ -1405,9 +1405,12 @@ public:
   {}
 
   /* opt_pass methods: */
-  opt_pass * clone () { return new pass_simduid_cleanup (m_ctxt); }
-  virtual bool gate (function *fun) { return fun->has_simduid_loops; }
-  virtual unsigned int execute (function *);
+  opt_pass * clone () final override
+  {
+    return new pass_simduid_cleanup (m_ctxt);
+  }
+  bool gate (function *fun) final override { return fun->has_simduid_loops; }
+  unsigned int execute (function *) final override;
 
 }; // class pass_simduid_cleanup
 
@@ -1463,9 +1466,9 @@ public:
   {}
 
   /* opt_pass methods: */
-  opt_pass * clone () { return new pass_slp_vectorize (m_ctxt); }
-  virtual bool gate (function *) { return flag_tree_slp_vectorize != 0; }
-  virtual unsigned int execute (function *);
+  opt_pass * clone () final override { return new pass_slp_vectorize (m_ctxt); }
+  bool gate (function *) final override { return flag_tree_slp_vectorize != 0; }
+  unsigned int execute (function *) final override;
 
 }; // class pass_slp_vectorize
 
@@ -1696,12 +1699,15 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *)
+  bool gate (function *) final override
     {
       return flag_section_anchors && flag_tree_loop_vectorize;
     }
 
-  virtual unsigned int execute (function *) { return increase_alignment (); }
+  unsigned int execute (function *) final override
+  {
+    return increase_alignment ();
+  }
 
 }; // class pass_ipa_increase_alignment
 
diff --git a/gcc/tree-vrp.cc b/gcc/tree-vrp.cc
index 0784d658567..da0a6d5a8b6 100644
--- a/gcc/tree-vrp.cc
+++ b/gcc/tree-vrp.cc
@@ -4402,14 +4402,14 @@ public:
   {}
 
   /* opt_pass methods: */
-  opt_pass * clone () { return new pass_vrp (m_ctxt); }
-  void set_pass_param (unsigned int n, bool param)
+  opt_pass * clone () final override { return new pass_vrp (m_ctxt); }
+  void set_pass_param (unsigned int n, bool param) final override
     {
       gcc_assert (n == 0);
       warn_array_bounds_p = param;
     }
-  virtual bool gate (function *) { return flag_tree_vrp != 0; }
-  virtual unsigned int execute (function *fun)
+  bool gate (function *) final override { return flag_tree_vrp != 0; }
+  unsigned int execute (function *fun) final override
     {
       if ((my_pass == 1 && param_vrp1_mode == VRP_MODE_RANGER)
 	  || (my_pass == 2 && param_vrp2_mode == VRP_MODE_RANGER))
diff --git a/gcc/tsan.cc b/gcc/tsan.cc
index 02e8ac7cf79..79d4582acd1 100644
--- a/gcc/tsan.cc
+++ b/gcc/tsan.cc
@@ -909,13 +909,13 @@ public:
   {}
 
   /* opt_pass methods: */
-  opt_pass * clone () { return new pass_tsan (m_ctxt); }
-  virtual bool gate (function *)
+  opt_pass * clone () final override { return new pass_tsan (m_ctxt); }
+  bool gate (function *) final override
 {
   return sanitize_flags_p (SANITIZE_THREAD);
 }
 
-  virtual unsigned int execute (function *) { return tsan_pass (); }
+  unsigned int execute (function *) final override { return tsan_pass (); }
 
 }; // class pass_tsan
 
@@ -950,12 +950,12 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *)
+  bool gate (function *) final override
     {
       return (sanitize_flags_p (SANITIZE_THREAD) && !optimize);
     }
 
-  virtual unsigned int execute (function *) { return tsan_pass (); }
+  unsigned int execute (function *) final override { return tsan_pass (); }
 
 }; // class pass_tsan_O0
 
diff --git a/gcc/ubsan.cc b/gcc/ubsan.cc
index 6c058142c37..18c75b471f4 100644
--- a/gcc/ubsan.cc
+++ b/gcc/ubsan.cc
@@ -2329,7 +2329,7 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *)
+  bool gate (function *) final override
     {
       return sanitize_flags_p ((SANITIZE_NULL | SANITIZE_SI_OVERFLOW
 				| SANITIZE_BOOL | SANITIZE_ENUM
@@ -2341,7 +2341,7 @@ public:
 				| SANITIZE_BUILTIN));
     }
 
-  virtual unsigned int execute (function *);
+  unsigned int execute (function *) final override;
 
 }; // class pass_ubsan
 
diff --git a/gcc/var-tracking.cc b/gcc/var-tracking.cc
index 7c3ad0a55bd..235981d100f 100644
--- a/gcc/var-tracking.cc
+++ b/gcc/var-tracking.cc
@@ -10592,12 +10592,12 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *)
+  bool gate (function *) final override
     {
       return (flag_var_tracking && !targetm.delay_vartrack);
     }
 
-  virtual unsigned int execute (function *)
+  unsigned int execute (function *) final override
     {
       return variable_tracking_main ();
     }
diff --git a/gcc/vtable-verify.cc b/gcc/vtable-verify.cc
index 48f9987082e..24894e7f108 100644
--- a/gcc/vtable-verify.cc
+++ b/gcc/vtable-verify.cc
@@ -818,8 +818,8 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *) { return (flag_vtable_verify); }
-  virtual unsigned int execute (function *);
+  bool gate (function *) final override { return (flag_vtable_verify); }
+  unsigned int execute (function *) final override;
 
 }; // class pass_vtable_verify
 
diff --git a/gcc/web.cc b/gcc/web.cc
index a5874a98825..bd0ec94f1f4 100644
--- a/gcc/web.cc
+++ b/gcc/web.cc
@@ -323,8 +323,8 @@ public:
   {}
 
   /* opt_pass methods: */
-  virtual bool gate (function *) { return (optimize > 0 && flag_web); }
-  virtual unsigned int execute (function *);
+  bool gate (function *) final override { return (optimize > 0 && flag_web); }
+  unsigned int execute (function *) final override;
 
 }; // class pass_web
 
