From 832f67e91c8b01614a1e08e4e7039e82d541af5d Mon Sep 17 00:00:00 2001
From: Tim Wojtulewicz <timwoj@gmail.com>
Date: Thu, 10 Jul 2025 21:28:54 -0700
Subject: [PATCH 1/2] Disable a few new modernize clang-tidy checkers, enabled
 by C++20

---
 .clang-tidy | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/.clang-tidy b/.clang-tidy
index f4b83da5f5..9bc2fc61ac 100644
--- a/.clang-tidy
+++ b/.clang-tidy
@@ -16,6 +16,7 @@ Checks: [-*,
          -bugprone-unchecked-optional-access,
          -performance-unnecessary-value-param,
          -modernize-use-equals-default,
+         -modernize-use-integer-sign-comparison,
 
          # The following cause either lots of pointless or advisory warnings
          -bugprone-easily-swappable-parameters,
@@ -43,6 +44,7 @@ Checks: [-*,
          -modernize-use-nodiscard,
          -modernize-use-ranges,
          -modernize-use-trailing-return-type,
+         -modernize-use-designated-initializers,
 
          # This one returns a bunch of findings in DFA and the sqlite library.
          # We're unlikely to fix either of them.
@@ -64,6 +66,10 @@ Checks: [-*,
          -modernize-use-std-format,
          -modernize-use-std-numbers,
          -modernize-use-std-print,
+
+         # C++20 supports constraints but until Spicy supports building with C++20
+         # this one has to stay disabled.
+         -modernize-use-constraints,
 ]
 
 HeaderFilterRegex: '.h'

From 8640f92b1fb48d0ed7be7f6a6d648aadf5e81750 Mon Sep 17 00:00:00 2001
From: Tim Wojtulewicz <timwoj@gmail.com>
Date: Thu, 10 Jul 2025 21:32:18 -0700
Subject: [PATCH 2/2] Use ranges::reverse_view to fix a few reverse ranged-for
 loops

---
 src/Func.cc                  | 7 +++----
 src/Scope.cc                 | 6 ++++--
 src/plugin/Manager.cc        | 5 +++--
 src/spicy/runtime-support.cc | 7 ++++---
 4 files changed, 14 insertions(+), 11 deletions(-)

diff --git a/src/Func.cc b/src/Func.cc
index 6f44bd6b6b..b7ac9a0d70 100644
--- a/src/Func.cc
+++ b/src/Func.cc
@@ -15,6 +15,7 @@
 #include <cerrno>
 #include <csignal>
 #include <cstdlib>
+#include <ranges>
 
 // Most of these includes are needed for code included from bif files.
 #include "zeek/Base64.h"
@@ -88,11 +89,10 @@ std::string render_call_stack() {
     if ( ! detail::call_stack.empty() )
         rval += "| ";
 
-    for ( auto it = detail::call_stack.rbegin(); it != detail::call_stack.rend(); ++it ) {
+    for ( auto& ci : std::ranges::reverse_view(detail::call_stack) ) {
         if ( lvl > 0 )
             rval += " | ";
 
-        auto& ci = *it;
         const auto& name = ci.func->GetName();
         std::string arg_desc;
 
@@ -938,8 +938,7 @@ zeek::VectorValPtr get_current_script_backtrace() {
     // to prevent problems with iterator invalidation.
     auto cs_copy = zeek::detail::call_stack;
 
-    for ( auto it = cs_copy.rbegin(); it != cs_copy.rend(); ++it ) {
-        const auto& ci = *it;
+    for ( const auto& ci : std::ranges::reverse_view(cs_copy) ) {
         if ( ! ci.func )
             // This happens for compiled code.
             continue;
diff --git a/src/Scope.cc b/src/Scope.cc
index 6be15e9cb6..b97dbe77d2 100644
--- a/src/Scope.cc
+++ b/src/Scope.cc
@@ -2,6 +2,8 @@
 
 #include "zeek/Scope.h"
 
+#include <ranges>
+
 #include "zeek/Desc.h"
 #include "zeek/ID.h"
 #include "zeek/IntrusivePtr.h"
@@ -112,8 +114,8 @@ const IDPtr& lookup_ID(const char* name, const char* curr_module, bool no_global
     if ( ! explicit_global ) {
         bool need_export = check_export && (ID_module != GLOBAL_MODULE_NAME && ID_module != curr_module);
 
-        for ( auto s_i = scopes.rbegin(); s_i != scopes.rend(); ++s_i ) {
-            const auto& id = (*s_i)->Find(fullname);
+        for ( const auto& s_i : std::ranges::reverse_view(scopes) ) {
+            const auto& id = s_i->Find(fullname);
 
             if ( id ) {
                 if ( need_export && ! id->IsExport() && ! in_debug )
diff --git a/src/plugin/Manager.cc b/src/plugin/Manager.cc
index a718295fa9..36f68862f1 100644
--- a/src/plugin/Manager.cc
+++ b/src/plugin/Manager.cc
@@ -12,6 +12,7 @@
 #include <cstdlib>
 #include <fstream>
 #include <optional>
+#include <ranges>
 #include <regex>
 #include <sstream>
 
@@ -375,8 +376,8 @@ void Manager::ActivateDynamicPlugins(bool all) {
 }
 
 void Manager::UpdateInputFiles() {
-    for ( file_list::const_reverse_iterator i = scripts_to_load.rbegin(); i != scripts_to_load.rend(); i++ )
-        add_input_file_at_front((*i).c_str());
+    for ( const auto& script : std::ranges::reverse_view(scripts_to_load) )
+        add_input_file_at_front(script.c_str());
 
     scripts_to_load.clear();
 }
diff --git a/src/spicy/runtime-support.cc b/src/spicy/runtime-support.cc
index 9006ec2389..ba321c9435 100644
--- a/src/spicy/runtime-support.cc
+++ b/src/spicy/runtime-support.cc
@@ -3,6 +3,7 @@
 #include "zeek/spicy/runtime-support.h"
 
 #include <memory>
+#include <ranges>
 
 #include <hilti/rt/exception.h>
 #include <hilti/rt/profiler.h>
@@ -886,9 +887,9 @@ const rt::cookie::FileState* rt::cookie::FileStateStack::find(const std::string&
     auto _ = hilti::rt::profiler::start("zeek/rt/file-stack-find");
 
     // Reverse search as the default state would be on top of the stack.
-    for ( auto i = _stack.rbegin(); i != _stack.rend(); i++ ) {
-        if ( i->fid == fid )
-            return &*i;
+    for ( const auto& i : std::ranges::reverse_view(_stack) ) {
+        if ( i.fid == fid )
+            return &i;
     }
 
     return nullptr;