From 57fea81f8a6ab3b91b1003d27bd48effad30b25a Mon Sep 17 00:00:00 2001
From: Eelco Dolstra <edolstra@gmail.com>
Date: Mon, 25 Nov 2024 15:59:43 +0100
Subject: [PATCH] Work around gcc warning
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This shuts up a 300-line warning that includes

  /nix/store/fg7ass3a5m5pgl26qzfdniicbwbgzccy-gcc-13.2.0/include/c++/13.2.0/bits/stl_tree.h:182:25: warning: ‘*(std::_Rb_tree_header*)((char*)&<unnamed> + offsetof(nix::value_type, nix::DerivedPath::<unnamed>.std::variant<nix::DerivedPathOpaque, nix::DerivedPathBuilt>::<unnamed>.std::__detail::__variant::_Variant_base<nix::DerivedPathOpaque, nix::DerivedPathBuilt>::<unnamed>.std::__detail::__variant::_Move_assign_base<false, nix::DerivedPathOpaque, nix::DerivedPathBuilt>::<unnamed>.std::__detail::__variant::_Copy_assign_base<false, nix::DerivedPathOpaque, nix::DerivedPathBuilt>::<unnamed>.std::__detail::__variant::_Move_ctor_base<false, nix::DerivedPathOpaque, nix::DerivedPathBuilt>::<unnamed>.std::__detail::__variant::_Copy_ctor_base<false, nix::DerivedPathOpaque, nix::DerivedPathBuilt>::<unnamed>.std::__detail::__variant::_Variant_storage<false, nix::DerivedPathOpaque, nix::DerivedPathBuilt>::_M_u) + 24).std::_Rb_tree_header::_M_header.std::_Rb_tree_node_base::_M_parent’ may be used uninitialized [-Wmaybe-uninitialized]
    182 |       if (__x._M_header._M_parent != nullptr)
        |           ~~~~~~~~~~~~~~^~~~~~~~~
---
 src/nix/flake.cc | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/src/nix/flake.cc b/src/nix/flake.cc
index ce2faacb0..925b66d3e 100644
--- a/src/nix/flake.cc
+++ b/src/nix/flake.cc
@@ -643,10 +643,11 @@ struct CmdFlakeCheck : FlakeCommand
                                             fmt("%s.%s.%s", name, attr_name, state->symbols[attr2.name]),
                                             *attr2.value, attr2.pos);
                                         if (drvPath && attr_name == settings.thisSystem.get()) {
-                                            drvPaths.push_back(DerivedPath::Built {
+                                            auto path = DerivedPath::Built {
                                                 .drvPath = makeConstantStorePathRef(*drvPath),
                                                 .outputs = OutputsSpec::All { },
-                                            });
+                                            };
+                                            drvPaths.push_back(std::move(path));
                                         }
                                     }
                                 }