From 2cf2bb45fcf8799430220853e14c566bdd5812a0 Mon Sep 17 00:00:00 2001
From: Eelco Dolstra <edolstra@gmail.com>
Date: Wed, 18 Oct 2023 19:32:20 +0200
Subject: [PATCH] Fix C++17 build

---
 src/libfetchers/tarball.cc | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/libfetchers/tarball.cc b/src/libfetchers/tarball.cc
index 07ce05506..546466716 100644
--- a/src/libfetchers/tarball.cc
+++ b/src/libfetchers/tarball.cc
@@ -308,7 +308,7 @@ struct TarballInputScheme : CurlInputScheme
             input = immutableInput;
         }
 
-        if (result.lastModified && !input.attrs.contains("lastModified"))
+        if (result.lastModified && !input.attrs.count("lastModified"))
             input.attrs.insert_or_assign("lastModified", uint64_t(result.lastModified));
 
         return {result.tree.storePath, std::move(input)};