https://bugs.gentoo.org/931305
https://github.com/lighttpd/lighttpd1.4/commit/524614455554163ec78b27b89ff52bbf7fe96958

From 524614455554163ec78b27b89ff52bbf7fe96958 Mon Sep 17 00:00:00 2001
From: Glenn Strauss <gstrauss@gluelogic.com>
Date: Wed, 24 Apr 2024 03:07:37 -0400
Subject: [PATCH] [core] special value for Linux POLLRDHUP on SPARC (fixes
 #3251)

x-ref:
  "[1.4.76] buildroot compile error with bootlin-sparc{64-g,-uc}libc"
  https://redmine.lighttpd.net/issues/3251
--- a/src/fdevent.h
+++ b/src/fdevent.h
@@ -40,6 +40,8 @@ struct fdnode_st {
 #if (defined(__sun) && defined(__SVR4)) /* Solaris */ \
  || defined(__FreeBSD__)
 #define FDEVENT_RDHUP  0x4000
+#elif (defined(__linux__) && (defined(__sparc__) || defined(__sparc)))
+#define FDEVENT_RDHUP  0x2800 /*(0x2000 EPOLLRDHUP | 0x0800 POLLRDHUP)*/
 #else
 #define FDEVENT_RDHUP  0x2000
 #endif
--- a/src/fdevent_impl.c
+++ b/src/fdevent_impl.c
@@ -338,6 +338,11 @@ fdevent_linux_sysepoll_event_set (fdevents *ev, fdnode *fdn, int events)
     struct epoll_event ep;
   #ifndef EPOLLRDHUP
     events &= ~FDEVENT_RDHUP;
+  #elif (defined(__linux__) && (defined(__sparc__) || defined(__sparc)))
+    if (events & FDEVENT_RDHUP) {
+        events &= ~FDEVENT_RDHUP;
+        events |= EPOLLRDHUP;
+    }
   #endif
     ep.events = events | EPOLLERR | EPOLLHUP;
     ep.data.ptr = fdn;
@@ -376,7 +381,11 @@ fdevent_linux_sysepoll_init (fdevents *ev)
     ck_static_assert(EPOLLERR   == FDEVENT_ERR);
     ck_static_assert(EPOLLHUP   == FDEVENT_HUP);
   #ifdef EPOLLRDHUP
+   #if (defined(__linux__) && (defined(__sparc__) || defined(__sparc)))
+    ck_static_assert(EPOLLRDHUP  & FDEVENT_RDHUP);
+   #else
     ck_static_assert(EPOLLRDHUP == FDEVENT_RDHUP);
+   #endif
   #endif
 
     ev->type      = FDEVENT_HANDLER_LINUX_SYSEPOLL;
@@ -770,6 +779,11 @@ fdevent_poll_event_set (fdevents *ev, fdnode *fdn, int events)
 
   #ifndef POLLRDHUP
     events &= ~FDEVENT_RDHUP;
+  #elif (defined(__linux__) && (defined(__sparc__) || defined(__sparc)))
+    if (events & FDEVENT_RDHUP) {
+        events &= ~FDEVENT_RDHUP;
+        events |= POLLRDHUP;
+    }
   #endif
 
     if (k >= 0) {
@@ -854,7 +868,11 @@ fdevent_poll_init (fdevents *ev)
     ck_static_assert(POLLHUP   == FDEVENT_HUP);
     ck_static_assert(POLLNVAL  == FDEVENT_NVAL);
   #ifdef POLLRDHUP
+   #if (defined(__linux__) && (defined(__sparc__) || defined(__sparc)))
+    ck_static_assert(POLLRDHUP  & FDEVENT_RDHUP);
+   #else
     ck_static_assert(POLLRDHUP == FDEVENT_RDHUP);
+   #endif
   #endif
 
     ev->type      = FDEVENT_HANDLER_POLL;