From: Florian Weimer <fweimer@redhat.com>
Date: Thu, 24 Nov 2022 11:57:49 +0100
Subject: [PATCH] configure.ac: C99 fix for
 ERTS___AFTER_MORECORE_HOOK_CAN_TRACK_MALLOC

#include <unistd.h> for the sbrk function if the header is available.

diff --git a/erts/configure b/erts/configure
index 44bbe9ef68..8a7d47b1f9 100755
--- a/erts/configure
+++ b/erts/configure
@@ -20672,6 +20672,9 @@ else $as_nop
 #ifdef HAVE_MALLOC_H
 #  include <malloc.h>
 #endif
+#ifdef HAVE_UNISTD_H
+#  include <unistd.h>
+#endif
 #if defined(HAVE_END_SYMBOL)
 extern char end;
 #elif defined(HAVE__END_SYMBOL)
diff --git a/erts/configure.ac b/erts/configure.ac
index f6bcbd11ff..617deafc42 100644
--- a/erts/configure.ac
+++ b/erts/configure.ac
@@ -2445,6 +2445,9 @@ AC_CACHE_CHECK([if __after_morecore_hook can track malloc()s core memory use],
 #ifdef HAVE_MALLOC_H
 #  include <malloc.h>
 #endif
+#ifdef HAVE_UNISTD_H
+#  include <unistd.h>
+#endif
 #if defined(HAVE_END_SYMBOL)
 extern char end;
 #elif defined(HAVE__END_SYMBOL)