Port configure script to C99

Related to:

  <https://fedoraproject.org/wiki/Changes/PortingToModernC>
  <https://fedoraproject.org/wiki/Toolchain/PortingToModernC>

spamassassin-configure-c99.patch

@@ -0,0 +1,62 @@
+Avoid implicit function declarations in the configure script.
+The undeclared exit function comes from autoconf-generated code.
+The SHUT_RD and h_errno checks are specific to the spamassassin
+package.
+
+Submitted upstream: <https://bz.apache.org/SpamAssassin/show_bug.cgi?id=8076>
+
+diff --git a/spamc/configure b/spamc/configure
+index d8e5dcf8a21d6a3d..5472d2b009fb9083 100755
+--- a/spamc/configure
++++ b/spamc/configure
+@@ -2624,8 +2624,8 @@ 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$ac_exeext
+@@ -3553,6 +3553,7 @@ _ACEOF
+ cat confdefs.h >>conftest.$ac_ext
+ cat >>conftest.$ac_ext <<_ACEOF
+ /* end confdefs.h.  */
++#include <stdio.h>
+ #include <sys/types.h>
+ #include <sys/socket.h>
+ int
+@@ -4252,6 +4253,7 @@ _ACEOF
+ cat confdefs.h >>conftest.$ac_ext
+ cat >>conftest.$ac_ext <<_ACEOF
+ /* end confdefs.h.  */
++#include <stdio.h>
+ #include <netdb.h>
+ int
+ main ()
+diff --git a/spamc/configure.in b/spamc/configure.in
+index 42cc998412075086..96769105ef640bc8 100644
+--- a/spamc/configure.in
++++ b/spamc/configure.in
+@@ -47,7 +47,8 @@ dnl ----------------------------------------------------------------------
+ 
+ AC_CACHE_CHECK([for SHUT_RD],
+        shutrd, [
+-                AC_TRY_COMPILE([#include <sys/types.h>
++                AC_TRY_COMPILE([#include <stdio.h>
++#include <sys/types.h>
+ #include <sys/socket.h>],
+                         [printf ("%d", SHUT_RD); return 0;],
+                                         [shutrd=yes],
+@@ -89,7 +90,8 @@ dnl ----------------------------------------------------------------------
+ 
+ AC_CACHE_CHECK([for h_errno],
+         herrno, [
+-                AC_TRY_COMPILE([#include <netdb.h>],
++                AC_TRY_COMPILE([#include <stdio.h>
++#include <netdb.h>],
+                         [printf ("%d", h_errno); return 0;],
+                                         [herrno=yes],
+                                         [herrno=no]),

spamassassin.spec

@@ -60,7 +60,7 @@ Summary: Spam filter for email which can be invoked from mail delivery agents
 Name: spamassassin
 Version: 3.4.6
 #Release: 0.8.%%{prerev}%%{?dist}
-Release: 7%{?dist}
+Release: 8%{?dist}
 License: ASL 2.0
 URL: https://spamassassin.apache.org/
 Source0: https://www.apache.org/dist/%{name}/source/%{real_name}-%{version}.tar.bz2
@@ -90,6 +90,7 @@ Source17: sa-update.timer
 # Switch to using gnupg2 instead of gnupg1
 Patch0: spamassassin-3.3.2-gnupg2.patch
 Patch1: spamassassin-3.4.1-add-logfile-homedir-options.patch
+Patch2: spamassassin-configure-c99.patch
 # end of patches
 Requires: perl(:MODULE_COMPAT_%(eval "`%{__perl} -V:version`"; echo $version))
 %if %{use_systemd} == 0
@@ -209,6 +210,7 @@ To filter spam for all users, add that line to /etc/procmailrc
 # Patches 0-99 are RH specific
 %patch0 -p1
 %patch1 -p1
+%patch2 -p1
 # end of patches
 
 echo "RHEL=%{?rhel} FEDORA=%{?fedora}"
@@ -388,6 +390,9 @@ exit 0
 %endif
 
 %changelog
+* Sun Nov 27 2022 Florian Weimer <fweimer@redhat.com> - 3.4.6-8
+- Port configure script to C99
+
 * Sat Jul 23 2022 Fedora Release Engineering <releng@fedoraproject.org> - 3.4.6-7
 - Rebuilt for https://fedoraproject.org/wiki/Fedora_37_Mass_Rebuild