diff --git a/configure b/configure
index 905be9568b..1ccdc5ca2c 100755
--- a/configure
+++ b/configure
@@ -12635,9 +12635,9 @@ fi
 
 if test "$with_gssapi" = yes ; then
   if test "$PORTNAME" != "win32"; then
-    { $as_echo "$as_me:${as_lineno-$LINENO}: checking for library containing gss_init_sec_context" >&5
-$as_echo_n "checking for library containing gss_init_sec_context... " >&6; }
-if ${ac_cv_search_gss_init_sec_context+:} false; then :
+    { $as_echo "$as_me:${as_lineno-$LINENO}: checking for library containing gss_store_cred_into" >&5
+$as_echo_n "checking for library containing gss_store_cred_into... " >&6; }
+if ${ac_cv_search_gss_store_cred_into+:} false; then :
   $as_echo_n "(cached) " >&6
 else
   ac_func_search_save_LIBS=$LIBS
@@ -12650,11 +12650,11 @@ cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 #ifdef __cplusplus
 extern "C"
 #endif
-char gss_init_sec_context ();
+char gss_store_cred_into ();
 int
 main ()
 {
-return gss_init_sec_context ();
+return gss_store_cred_into ();
   ;
   return 0;
 }
@@ -12667,30 +12667,30 @@ for ac_lib in '' gssapi_krb5 gss 'gssapi -lkrb5 -lcrypto'; do
     LIBS="-l$ac_lib  $ac_func_search_save_LIBS"
   fi
   if ac_fn_c_try_link "$LINENO"; then :
-  ac_cv_search_gss_init_sec_context=$ac_res
+  ac_cv_search_gss_store_cred_into=$ac_res
 fi
 rm -f core conftest.err conftest.$ac_objext \
     conftest$ac_exeext
-  if ${ac_cv_search_gss_init_sec_context+:} false; then :
+  if ${ac_cv_search_gss_store_cred_into+:} false; then :
   break
 fi
 done
-if ${ac_cv_search_gss_init_sec_context+:} false; then :
+if ${ac_cv_search_gss_store_cred_into+:} false; then :
 
 else
-  ac_cv_search_gss_init_sec_context=no
+  ac_cv_search_gss_store_cred_into=no
 fi
 rm conftest.$ac_ext
 LIBS=$ac_func_search_save_LIBS
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_search_gss_init_sec_context" >&5
-$as_echo "$ac_cv_search_gss_init_sec_context" >&6; }
-ac_res=$ac_cv_search_gss_init_sec_context
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_search_gss_store_cred_into" >&5
+$as_echo "$ac_cv_search_gss_store_cred_into" >&6; }
+ac_res=$ac_cv_search_gss_store_cred_into
 if test "$ac_res" != no; then :
   test "$ac_res" = "none required" || LIBS="$ac_res $LIBS"
 
 else
-  as_fn_error $? "could not find function 'gss_init_sec_context' required for GSSAPI" "$LINENO" 5
+  as_fn_error $? "could not find function 'gss_store_cred_into' required for GSSAPI" "$LINENO" 5
 fi
 
   else
@@ -14104,6 +14104,33 @@ done
 
 fi
 
+done
+
+  for ac_header in gssapi/gssapi_ext.h
+do :
+  ac_fn_c_check_header_mongrel "$LINENO" "gssapi/gssapi_ext.h" "ac_cv_header_gssapi_gssapi_ext_h" "$ac_includes_default"
+if test "x$ac_cv_header_gssapi_gssapi_ext_h" = xyes; then :
+  cat >>confdefs.h <<_ACEOF
+#define HAVE_GSSAPI_GSSAPI_EXT_H 1
+_ACEOF
+
+else
+  for ac_header in gssapi_ext.h
+do :
+  ac_fn_c_check_header_mongrel "$LINENO" "gssapi_ext.h" "ac_cv_header_gssapi_ext_h" "$ac_includes_default"
+if test "x$ac_cv_header_gssapi_ext_h" = xyes; then :
+  cat >>confdefs.h <<_ACEOF
+#define HAVE_GSSAPI_EXT_H 1
+_ACEOF
+
+else
+  as_fn_error $? "gssapi_ext.h header file is required for GSSAPI" "$LINENO" 5
+fi
+
+done
+
+fi
+
 done
 
 fi
@@ -15321,7 +15348,7 @@ else
     We can't simply define LARGE_OFF_T to be 9223372036854775807,
     since some C++ compilers masquerading as C compilers
     incorrectly reject 9223372036854775807.  */
-#define LARGE_OFF_T (((off_t) 1 << 62) - 1 + ((off_t) 1 << 62))
+#define LARGE_OFF_T ((((off_t) 1 << 31) << 31) - 1 + (((off_t) 1 << 31) << 31))
   int off_t_is_large[(LARGE_OFF_T % 2147483629 == 721
 		       && LARGE_OFF_T % 2147483647 == 1)
 		      ? 1 : -1];
@@ -15367,7 +15394,7 @@ else
     We can't simply define LARGE_OFF_T to be 9223372036854775807,
     since some C++ compilers masquerading as C compilers
     incorrectly reject 9223372036854775807.  */
-#define LARGE_OFF_T (((off_t) 1 << 62) - 1 + ((off_t) 1 << 62))
+#define LARGE_OFF_T ((((off_t) 1 << 31) << 31) - 1 + (((off_t) 1 << 31) << 31))
   int off_t_is_large[(LARGE_OFF_T % 2147483629 == 721
 		       && LARGE_OFF_T % 2147483647 == 1)
 		      ? 1 : -1];
@@ -15391,7 +15418,7 @@ rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
     We can't simply define LARGE_OFF_T to be 9223372036854775807,
     since some C++ compilers masquerading as C compilers
     incorrectly reject 9223372036854775807.  */
-#define LARGE_OFF_T (((off_t) 1 << 62) - 1 + ((off_t) 1 << 62))
+#define LARGE_OFF_T ((((off_t) 1 << 31) << 31) - 1 + (((off_t) 1 << 31) << 31))
   int off_t_is_large[(LARGE_OFF_T % 2147483629 == 721
 		       && LARGE_OFF_T % 2147483647 == 1)
 		      ? 1 : -1];
@@ -15436,7 +15463,7 @@ else
     We can't simply define LARGE_OFF_T to be 9223372036854775807,
     since some C++ compilers masquerading as C compilers
     incorrectly reject 9223372036854775807.  */
-#define LARGE_OFF_T (((off_t) 1 << 62) - 1 + ((off_t) 1 << 62))
+#define LARGE_OFF_T ((((off_t) 1 << 31) << 31) - 1 + (((off_t) 1 << 31) << 31))
   int off_t_is_large[(LARGE_OFF_T % 2147483629 == 721
 		       && LARGE_OFF_T % 2147483647 == 1)
 		      ? 1 : -1];
@@ -15460,7 +15487,7 @@ rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
     We can't simply define LARGE_OFF_T to be 9223372036854775807,
     since some C++ compilers masquerading as C compilers
     incorrectly reject 9223372036854775807.  */
-#define LARGE_OFF_T (((off_t) 1 << 62) - 1 + ((off_t) 1 << 62))
+#define LARGE_OFF_T ((((off_t) 1 << 31) << 31) - 1 + (((off_t) 1 << 31) << 31))
   int off_t_is_large[(LARGE_OFF_T % 2147483629 == 721
 		       && LARGE_OFF_T % 2147483647 == 1)
 		      ? 1 : -1];
diff --git a/configure.ac b/configure.ac
index 8095dfcf1d..7ba969b1b1 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1340,8 +1340,8 @@ fi
 
 if test "$with_gssapi" = yes ; then
   if test "$PORTNAME" != "win32"; then
-    AC_SEARCH_LIBS(gss_init_sec_context, [gssapi_krb5 gss 'gssapi -lkrb5 -lcrypto'], [],
-                   [AC_MSG_ERROR([could not find function 'gss_init_sec_context' required for GSSAPI])])
+    AC_SEARCH_LIBS(gss_store_cred_into, [gssapi_krb5 gss 'gssapi -lkrb5 -lcrypto'], [],
+                   [AC_MSG_ERROR([could not find function 'gss_store_cred_into' required for GSSAPI])])
   else
     LIBS="$LIBS -lgssapi32"
   fi
@@ -1562,6 +1562,8 @@ fi
 if test "$with_gssapi" = yes ; then
   AC_CHECK_HEADERS(gssapi/gssapi.h, [],
 	[AC_CHECK_HEADERS(gssapi.h, [], [AC_MSG_ERROR([gssapi.h header file is required for GSSAPI])])])
+  AC_CHECK_HEADERS(gssapi/gssapi_ext.h, [],
+	[AC_CHECK_HEADERS(gssapi_ext.h, [], [AC_MSG_ERROR([gssapi_ext.h header file is required for GSSAPI])])])
 fi
 
 PGAC_PATH_PROGS(OPENSSL, openssl)
diff --git a/src/include/pg_config.h.in b/src/include/pg_config.h.in
index 3665e799e7..6d572c3820 100644
--- a/src/include/pg_config.h.in
+++ b/src/include/pg_config.h.in
@@ -196,6 +196,12 @@
 /* Define to 1 if you have the `getpeerucred' function. */
 #undef HAVE_GETPEERUCRED
 
+/* Define to 1 if you have the <gssapi_ext.h> header file. */
+#undef HAVE_GSSAPI_EXT_H
+
+/* Define to 1 if you have the <gssapi/gssapi_ext.h> header file. */
+#undef HAVE_GSSAPI_GSSAPI_EXT_H
+
 /* Define to 1 if you have the <gssapi/gssapi.h> header file. */
 #undef HAVE_GSSAPI_GSSAPI_H