Avoid implicit function declarations in configure (#2144890)

execstack-configure-c99.patch

@@ -0,0 +1,37 @@
+Avoid implicit function declarations, a C feature removed in 1999.
+
+diff --git a/aclocal.m4 b/aclocal.m4
+index a357ef74b30a09a6..2d2af334d5369e8e 100644
+--- a/aclocal.m4
++++ b/aclocal.m4
+@@ -6727,6 +6727,7 @@ AC_DEFUN(AC_LIBELF_SXWORD,
+ #include <stdlib.h>
+ #include <stdio.h>
+ #include <string.h>
++#include <unistd.h>
+ 
+ static unsigned char sparc64_elf[] = {
+ 0x7f,0x45,0x4c,0x46,0x02,0x02,0x01,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
+diff --git a/configure b/configure
+index 9f2a746fbf3f7471..960e140559761417 100755
+--- a/configure
++++ b/configure
+@@ -4438,8 +4438,8 @@ main ()
+   for (i = 0; i < 256; i++)
+     if (XOR (islower (i), ISLOWER (i))
+         || toupper (i) != TOUPPER (i))
+-      exit(2);
+-  exit (0);
++      return 2;
++  return 0;
+ }
+ _ACEOF
+ rm -f conftest$ac_exeext
+@@ -19411,6 +19411,7 @@ cat >>conftest.$ac_ext <<_ACEOF
+ #include <stdlib.h>
+ #include <stdio.h>
+ #include <string.h>
++#include <unistd.h>
+ 
+ static unsigned char sparc64_elf[] = {
+ 0x7f,0x45,0x4c,0x46,0x02,0x02,0x01,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,

execstack.spec

@@ -1,6 +1,6 @@
 Name:           execstack
 Version:        0.5.0
-Release:        23%{?dist}
+Release:        24%{?dist}
 Summary:        Utility to set/clear/query executable stack bit
 
 %global commit 4c79120bcdbde0616f592458ccde7035e92ca3d8
@@ -11,6 +11,7 @@ License: GPLv2+
 Source0: https://github.com/keszybz/prelink/archive/%{commit}.tar.gz#/prelink-%{shortcommit}.tar.gz
 
 Patch0:  Add-PL_ARCH-for-AArch64.patch
+Patch1: execstack-configure-c99.patch
 
 BuildRequires: gcc
 BuildRequires: gcc-c++
@@ -58,6 +59,9 @@ install -Dm0644 doc/execstack.8 %{buildroot}%{_mandir}/man8/execstack.8
 %{_mandir}/man8/execstack.8.*
 
 %changelog
+* Tue Nov 22 2022 Florian Weimer <fweimer@redhat.com> - 0.5.0-24
+- Avoid implicit function declarations in configure (#2144890)
+
 * Thu Jul 21 2022 Fedora Release Engineering <releng@fedoraproject.org> - 0.5.0-23
 - Rebuilt for https://fedoraproject.org/wiki/Fedora_37_Mass_Rebuild