fix: compile errors with clang 21

Upgrade to nixpkgs 2025-11-13 to obtain clang 21.

* compile with Wdangling-assignment from clang 21
* fix EREPORT_CURL_MULTI_SETOPT compile failures due to type mismatch

Author: steve-chavez

shell.nix

@@ -1,7 +1,7 @@
 with import (builtins.fetchTarball {
-    name = "25.05";
-    url = "https://github.com/NixOS/nixpkgs/archive/refs/tags/25.05.tar.gz";
-    sha256 = "sha256:1915r28xc4znrh2vf4rrjnxldw2imysz819gzhk9qlrkqanmfsxd";
+  name = "2025-11-13";
+  url = "https://github.com/NixOS/nixpkgs/archive/91c9a64ce2a84e648d0cf9671274bb9c2fb9ba60.tar.gz";
+  sha256 = "sha256:19myp93spfsf5x62k6ncan7020bmbn80kj4ywcykqhb9c3q8fdr1";
 }) {};
 mkShell {
   buildInputs =

src/core.c

@@ -273,21 +273,24 @@ void insert_response(CurlHandle *handle, CURLcode curl_return_code) {
     vals[5]  = BoolGetDatum(false);
     nulls[5] = ' ';
   } else {
-    bool  timed_out = curl_return_code == CURLE_OPERATION_TIMEDOUT;
-    char *error_msg = NULL;
-
-    if (timed_out) {
-      error_msg = detailed_timeout_strerror(handle->ez_handle, handle->timeout_milliseconds).msg;
-    } else {
-      error_msg = (char *)curl_easy_strerror(curl_return_code);
-    }
+    bool timed_out = curl_return_code == CURLE_OPERATION_TIMEDOUT;
 
     vals[5]  = BoolGetDatum(timed_out);
     nulls[5] = ' ';
 
-    if (error_msg) {
-      vals[6]  = CStringGetTextDatum(error_msg);
+    if (timed_out) {
+      curl_timeout_msg timeout_msg =
+          detailed_timeout_strerror(handle->ez_handle, handle->timeout_milliseconds);
+
+      vals[6]  = CStringGetTextDatum(timeout_msg.msg);
       nulls[6] = ' ';
+    } else {
+      const char *error_msg = curl_easy_strerror(curl_return_code);
+
+      if (error_msg) {
+        vals[6]  = CStringGetTextDatum(error_msg);
+        nulls[6] = ' ';
+      }
     }
   }
 

src/event.c

@@ -27,7 +27,8 @@ void ev_monitor_close(WorkerState *wstate) {
   close(timerfd);
 }
 
-int multi_timer_cb(__attribute__((unused)) CURLM *multi, long timeout_ms, WorkerState *wstate) {
+int multi_timer_cb(__attribute__((unused)) CURLM *multi, long timeout_ms, void *userp) {
+  WorkerState *wstate = (WorkerState *)userp;
   elog(DEBUG2, "multi_timer_cb: Setting timeout to %ld ms\n", timeout_ms);
 
   if (!timer_created) {
@@ -72,7 +73,8 @@ int multi_timer_cb(__attribute__((unused)) CURLM *multi, long timeout_ms, Worker
 }
 
 int multi_socket_cb(__attribute__((unused)) CURL *easy, curl_socket_t sockfd, int what,
-                    WorkerState *wstate, void *socketp) {
+                    void *userp, void *socketp) {
+  WorkerState *wstate = (WorkerState *)userp;
   static char *whatstrs[] = {"NONE", "CURL_POLL_IN", "CURL_POLL_OUT", "CURL_POLL_INOUT",
                              "CURL_POLL_REMOVE"};
   elog(DEBUG2, "multi_socket_cb: sockfd %d received %s", sockfd, whatstrs[what]);
@@ -145,7 +147,8 @@ void ev_monitor_close(WorkerState *wstate) {
   close(wstate->epfd);
 }
 
-int multi_timer_cb(__attribute__((unused)) CURLM *multi, long timeout_ms, WorkerState *wstate) {
+int multi_timer_cb(__attribute__((unused)) CURLM *multi, long timeout_ms, void *userp) {
+  WorkerState *wstate = (WorkerState *)userp;
   elog(DEBUG2, "multi_timer_cb: Setting timeout to %ld ms\n", timeout_ms);
   event timer_event;
   int   id = 1;
@@ -172,7 +175,8 @@ int multi_timer_cb(__attribute__((unused)) CURLM *multi, long timeout_ms, Worker
 }
 
 int multi_socket_cb(__attribute__((unused)) CURL *easy, curl_socket_t sockfd, int what,
-                    WorkerState *wstate, void *socketp) {
+                    void *userp, void *socketp) {
+  WorkerState *wstate = (WorkerState *)userp;
   static char *whatstrs[] = {"NONE", "CURL_POLL_IN", "CURL_POLL_OUT", "CURL_POLL_INOUT",
                              "CURL_POLL_REMOVE"};
   elog(DEBUG2, "multi_socket_cb: sockfd %d received %s", sockfd, whatstrs[what]);

src/event.h

@@ -29,8 +29,8 @@ typedef struct kevent event;
 int  wait_event(int fd, event *events, size_t maxevents, int wait_milliseconds);
 int  event_monitor(void);
 void ev_monitor_close(WorkerState *wstate);
-int  multi_timer_cb(CURLM *multi, long timeout_ms, WorkerState *wstate);
-int multi_socket_cb(CURL *easy, curl_socket_t sockfd, int what, WorkerState *wstate, void *socketp);
+int  multi_timer_cb(CURLM *multi, long timeout_ms, void *userp);
+int  multi_socket_cb(CURL *easy, curl_socket_t sockfd, int what, void *userp, void *socketp);
 bool is_timer(event ev);
 int  get_curl_event(event ev);
 int  get_socket_fd(event ev);