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 2044690dc6..f31d7775a4 100755
--- a/erts/configure
+++ b/erts/configure
@@ -20937,6 +20937,9 @@ 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 f247c1e71f..59c4d05460 100644
--- a/erts/configure.ac
+++ b/erts/configure.ac
@@ -2459,6 +2459,9 @@ 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)