From a5216b282828a3e7ff86d11d61daafa0a002f87b Mon Sep 17 00:00:00 2001
From: firewave <firewave@users.noreply.github.com>
Date: Tue, 3 Jan 2023 03:06:30 +0100
Subject: [PATCH] only perform `__has_include` simplification if code is C++17
 or later

---
 simplecpp.cpp | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/simplecpp.cpp b/simplecpp.cpp
index ff72d412..f66fcdaa 100755
--- a/simplecpp.cpp
+++ b/simplecpp.cpp
@@ -2540,6 +2540,9 @@ static bool isCpp17OrLater(const simplecpp::DUI &dui)
 static std::string openHeader(std::ifstream &f, const simplecpp::DUI &dui, const std::string &sourcefile, const std::string &header, bool systemheader);
 static void simplifyHasInclude(simplecpp::TokenList &expr, const simplecpp::DUI &dui)
 {
+    if (!isCpp17OrLater(dui))
+        return;
+
     for (simplecpp::Token *tok = expr.front(); tok; tok = tok->next) {
         if (tok->str() != HAS_INCLUDE)
             continue;