Apply patch to fix C++20 compilation when building

build-cmd.sh

@@ -1,6 +1,7 @@
 #!/usr/bin/env bash
 
 cd "$(dirname "$0")"
+top="$(pwd)"
 
 # turn on verbose debugging output for parabuild logs.
 exec 4>&1; export BASH_XTRACEFD=4; set -x
@@ -41,3 +42,8 @@ pushd "$WEBSOCKETPP_SOURCE_DIR"
     mkdir -p "$stage/LICENSES"
     cp COPYING "$stage/LICENSES/websocketpp.txt"
 popd
+
+# Apply C++20 fixes from websocketpp's PRs
+# Note that this patches the build artifacts, not the source!
+# This only makes sense because this is a header-only library anyhow.
+patch --directory "$stage/include/" -p1 < "$top/patches/fix-cpp20-build.patch"

patches/fix-cpp20-build.patch

@@ -0,0 +1,109 @@
+From 39c4dd128b0c2d0f12f76137b175966b83f535ba Mon Sep 17 00:00:00 2001
+From: snag24 <45948878+snag24@users.noreply.github.com>
+Date: Thu, 5 Jun 2025 13:51:32 +0530
+Subject: [PATCH 1/2] Update endpoint.hpp
+
+---
+ websocketpp/endpoint.hpp | 4 ++--
+ 1 file changed, 2 insertions(+), 2 deletions(-)
+
+diff --git a/websocketpp/endpoint.hpp b/websocketpp/endpoint.hpp
+index c124b1d9a..91c348f10 100644
+--- a/websocketpp/endpoint.hpp
++++ b/websocketpp/endpoint.hpp
+@@ -43,7 +43,7 @@ class endpoint : public config::transport_type, public config::endpoint_base {
+ public:
+     // Import appropriate types from our helper class
+     // See endpoint_types for more details.
+-    typedef endpoint<connection,config> type;
++    typedef endpoint type;
+
+     /// Type of the transport component of this endpoint
+     typedef typename config::transport_type transport_type;
+@@ -109,7 +109,7 @@ class endpoint : public config::transport_type, public config::endpoint_base {
+
+
+     /// Destructor
+-    ~endpoint<connection,config>() {}
++    ~endpoint() {}
+
+     #ifdef _WEBSOCKETPP_DEFAULT_DELETE_FUNCTIONS_
+         // no copy constructor because endpoints are not copyable
+
+From 2638897e78d1bab9357c4fba11367f6ec0bab0db Mon Sep 17 00:00:00 2001
+From: snag24 <45948878+snag24@users.noreply.github.com>
+Date: Thu, 5 Jun 2025 13:56:00 +0530
+Subject: [PATCH 2/2] c++20 patch
+
+---
+ websocketpp/logger/basic.hpp | 18 +++++++++---------
+ 1 file changed, 9 insertions(+), 9 deletions(-)
+
+diff --git a/websocketpp/logger/basic.hpp b/websocketpp/logger/basic.hpp
+index 84514130e..f0e490e6d 100644
+--- a/websocketpp/logger/basic.hpp
++++ b/websocketpp/logger/basic.hpp
+@@ -58,33 +58,33 @@ namespace log {
+ template <typename concurrency, typename names>
+ class basic {
+ public:
+-    basic<concurrency,names>(channel_type_hint::value h =
++    basic(channel_type_hint::value h =
+         channel_type_hint::access)
+       : m_static_channels(0xffffffff)
+       , m_dynamic_channels(0)
+       , m_out(h == channel_type_hint::error ? &std::cerr : &std::cout) {}
+
+-    basic<concurrency,names>(std::ostream * out)
++    basic(std::ostream * out)
+       : m_static_channels(0xffffffff)
+       , m_dynamic_channels(0)
+       , m_out(out) {}
+
+-    basic<concurrency,names>(level c, channel_type_hint::value h =
++    basic(level c, channel_type_hint::value h =
+         channel_type_hint::access)
+       : m_static_channels(c)
+       , m_dynamic_channels(0)
+       , m_out(h == channel_type_hint::error ? &std::cerr : &std::cout) {}
+
+-    basic<concurrency,names>(level c, std::ostream * out)
++    basic(level c, std::ostream * out)
+       : m_static_channels(c)
+       , m_dynamic_channels(0)
+       , m_out(out) {}
+
+     /// Destructor
+-    ~basic<concurrency,names>() {}
++    ~basic() {}
+
+     /// Copy constructor
+-    basic<concurrency,names>(basic<concurrency,names> const & other)
++    basic(basic<concurrency,names> const & other)
+      : m_static_channels(other.m_static_channels)
+      , m_dynamic_channels(other.m_dynamic_channels)
+      , m_out(other.m_out)
+@@ -92,12 +92,12 @@ class basic {
+
+ #ifdef _WEBSOCKETPP_DEFAULT_DELETE_FUNCTIONS_
+     // no copy assignment operator because of const member variables
+-    basic<concurrency,names> & operator=(basic<concurrency,names> const &) = delete;
++    basic & operator=(basic<concurrency,names> const &) = delete;
+ #endif // _WEBSOCKETPP_DEFAULT_DELETE_FUNCTIONS_
+
+ #ifdef _WEBSOCKETPP_MOVE_SEMANTICS_
+     /// Move constructor
+-    basic<concurrency,names>(basic<concurrency,names> && other)
++    basic(basic<concurrency,names> && other)
+      : m_static_channels(other.m_static_channels)
+      , m_dynamic_channels(other.m_dynamic_channels)
+      , m_out(other.m_out)
+@@ -105,7 +105,7 @@ class basic {
+
+ #ifdef _WEBSOCKETPP_DEFAULT_DELETE_FUNCTIONS_
+     // no move assignment operator because of const member variables
+-    basic<concurrency,names> & operator=(basic<concurrency,names> &&) = delete;
++    basic & operator=(basic<concurrency,names> &&) = delete;
+ #endif // _WEBSOCKETPP_DEFAULT_DELETE_FUNCTIONS_
+
+ #endif // _WEBSOCKETPP_MOVE_SEMANTICS_