From f62799aa0360fa7c66d969d3c7e88b829d4d5506 Mon Sep 17 00:00:00 2001
From: Yiyu Zhou <yiyu@yiyuzhou.io>
Date: Tue, 29 Sep 2026 23:13:40 -0700
Subject: [PATCH] mumble: fix build with C++20

---
 .../networking/mumble/default.nix             |  1 +
 .../mumble/fix-plugin-updater-cxx20.patch     | 34 +++++++++++++++++++
 2 files changed, 35 insertions(+)
 create mode 100644 pkgs/applications/networking/mumble/fix-plugin-updater-cxx20.patch

diff --git a/pkgs/applications/networking/mumble/default.nix b/pkgs/applications/networking/mumble/default.nix
index 4b35a7438f79..39a9a98fbffd 100644
--- a/pkgs/applications/networking/mumble/default.nix
+++ b/pkgs/applications/networking/mumble/default.nix
@@ -154,6 +154,7 @@ let
 
       patches = [
         ./fix-plugin-copy.patch
+        ./fix-plugin-updater-cxx20.patch
       ];
 
       postInstall = lib.optionalString stdenv.hostPlatform.isDarwin ''
diff --git a/pkgs/applications/networking/mumble/fix-plugin-updater-cxx20.patch b/pkgs/applications/networking/mumble/fix-plugin-updater-cxx20.patch
new file mode 100644
index 000000000000..7badef93dadb
--- /dev/null
+++ b/pkgs/applications/networking/mumble/fix-plugin-updater-cxx20.patch
@@ -0,0 +1,34 @@
+Backported from upstream commit a2d5c363b5e457ed842971d68f8b945247cc4a04
+("REFAC(plugin): Add constructors to UpdateEntry struct"), which landed on
+master but was never backported to the 1.5.x branch.  Adjusted for the
+member ordering used in 1.5.x.
+
+UpdateEntry declares a defaulted default constructor, which keeps it an
+aggregate under C++17 but not under C++20, so the brace-enclosed initialiser
+below stops compiling.  abseil-cpp exports cxx_std_20 as an interface compile
+feature and protobuf::libprotobuf propagates it, which raises the standard used
+for the client targets above the C++17 requested via CMAKE_CXX_STANDARD.
+
+--- a/src/mumble/PluginUpdater.h
++++ b/src/mumble/PluginUpdater.h
+@@ -29,6 +29,8 @@
+ /// the same plugin.
+ struct UpdateEntry {
+ 	UpdateEntry() = default;
++	explicit UpdateEntry(plugin_id_t id, const QUrl &url, const QString &name, int redirectCount = 0)
++		: pluginID(id), updateURL(url), fileName(name), redirects(redirectCount) {}
+ 
+ 	plugin_id_t pluginID = std::numeric_limits< plugin_id_t >::max();
+ 	QUrl updateURL;
+--- a/src/mumble/PluginUpdater.cpp
++++ b/src/mumble/PluginUpdater.cpp
+@@ -45,8 +45,7 @@
+ 				QUrl updateURL = plugin->getUpdateDownloadURL();
+ 
+ 				if (updateURL.isValid() && !updateURL.isEmpty() && !updateURL.fileName().isEmpty()) {
+-					UpdateEntry entry = { plugin->getID(), updateURL, updateURL.fileName(), 0 };
+-					m_pluginsToUpdate << entry;
++					m_pluginsToUpdate.append(UpdateEntry(plugin->getID(), updateURL, updateURL.fileName()));
+ 				}
+ 			}
+