diff --git a/configure.in b/configure.in
index c10ed02..de25ff0 100644
--- a/configure.in
+++ b/configure.in
@@ -812,10 +812,10 @@ AC_ARG_WITH(valgrind,
     save_cppflags="$CPPFLAGS"
     AC_MSG_CHECKING(for valgrind.h usability)
     if test "x$withval" = xyes ; then
-	AC_COMPILE_IFELSE([#include <valgrind.h>], found=yes)
+	AC_COMPILE_IFELSE([AC_LANG_SOURCE([[#include <valgrind.h>]])], found=yes)
 	if test x$found = xno ; then
 	    CPPFLAGS="$CPPFLAGS -I/usr/include/valgrind"
-	    AC_COMPILE_IFELSE([#include <valgrind.h>], found=yes,
+	    AC_COMPILE_IFELSE([AC_LANG_SOURCE([[#include <valgrind.h>]])], found=yes,
 		CPPFLAGS="$save_cppflags")
 	fi
     else
@@ -823,7 +823,7 @@ AC_ARG_WITH(valgrind,
 	         $withval/valgrind $withval/include/valgrind
 	do
 	    CPPFLAGS="$CPPFLAGS -I$d"
-	    AC_COMPILE_IFELSE([#include <valgrind.h>], found=yes,
+	    AC_COMPILE_IFELSE([AC_LANG_SOURCE([[#include <valgrind.h>]])], found=yes,
 		CPPFLAGS="$save_cppflags")
 	    if test x$found = xyes ; then
 		break
diff --git a/maint/config/bdb.m4 b/maint/config/bdb.m4
index 9e17735..0df7308 100644
--- a/maint/config/bdb.m4
+++ b/maint/config/bdb.m4
@@ -17,14 +17,14 @@ AC_DEFUN([AX_BERKELEY_DB],
 	oldcflags=$CFLAGS
 	for dbheader in db4 db3 notfound; do
 		AC_COMPILE_IFELSE(
-			[#include "$dbpath/include/$dbheader/db.h"],
+			[AC_LANG_SOURCE([[#include "$dbpath/include/$dbheader/db.h"]])],
 			[DB_CFLAGS="-I$dbpath/include/$dbheader/"
 			 break])
 	done
 
 	if test "x$dbheader" = "xnotfound"; then
 		AC_COMPILE_IFELSE(
-			[#include "$dbpath/include/db.h"],
+			[AC_LANG_SOURCE([[#include "$dbpath/include/db.h"]])],
 			[DB_CFLAGS="-I$dbpath/include/"],
 			[AC_MSG_FAILURE(
 				Invalid libdb path specified. No db.h found.)])
@@ -37,8 +37,8 @@ AC_DEFUN([AX_BERKELEY_DB],
 	DB_LIB="-ldb"
 	CFLAGS="$DB_CFLAGS $oldcflags"
 	AC_TRY_LINK(
-		[#include <db.h>],
-		[DB *dbp; db_create(&dbp, NULL, 0);],
+		[AC_LANG_SOURCE([[#include <db.h>]])],
+		[AC_LANG_SOURCE([[DB *dbp; db_create(&dbp, NULL, 0);]])],
 		lib=db)
 	CFLAGS=$oldcflags
 	
@@ -47,8 +47,8 @@ AC_DEFUN([AX_BERKELEY_DB],
            LIBS="${oldlibs} -l$lib -lpthread"
            DB_LIB="-l$lib"
            AC_TRY_LINK(
-                  [#include <db.h>],
-                  [DB *dbp; db_create(&dbp, NULL, 0);],
+                  [AC_LANG_SOURCE([[#include <db.h>]])],
+                  [AC_LANG_SOURCE([[DB *dbp; db_create(&dbp, NULL, 0);]])],
                   [break])
         done
     fi
@@ -85,20 +85,23 @@ AC_DEFUN([AX_BERKELEY_DB],
     AC_MSG_CHECKING(for dbenv parameter to DB error callback function)
     oldcflags=$CFLAGS
     CFLAGS="$USR_CFLAGS $DB_CFLAGS -Werror"
-    AC_TRY_COMPILE([
-    #include <db.h>
+    AC_TRY_COMPILE(
+    [AC_LANG_SOURCE([[
+        #include <db.h>
     
-    void error_callback_fn(const DB_ENV *dbenv,
-                           const char *prefix,
-                           const char *message)
-    {
-        return;
-    }
-    ], [
-    DB *db;
+        void error_callback_fn(const DB_ENV *dbenv,
+                               const char *prefix,
+                               const char *message)
+        {
+            return;
+        }
+    ]])], 
+    [AC_LANG_SOURCE([[
+            DB *db;
     
-    db->set_errcall(db, error_callback_fn);
-    ], AC_MSG_RESULT(yes)
+            db->set_errcall(db, error_callback_fn);
+    ]])], 
+    AC_MSG_RESULT(yes)
     AC_DEFINE(HAVE_DBENV_PARAMETER_TO_DB_ERROR_CALLBACK, 1,
     Define if DB error callback function takes dbenv parameter)
     have_dbenv_parameter_to_db_error_callback=yes,
@@ -110,7 +113,7 @@ AC_DEFUN([AX_BERKELEY_DB],
         dnl not.
         dnl NOTE: still using -Werror!
         AC_MSG_CHECKING(if third parameter to error callback function is const)
-        AC_TRY_COMPILE([
+        AC_TRY_COMPILE([AC_LANG_SOURCE([[
         #include <db.h>
         
         void error_callback_fn(const DB_ENV *dbenv,
@@ -119,11 +122,11 @@ AC_DEFUN([AX_BERKELEY_DB],
         {
             return;
         }
-        ], [
+        ]])], [AC_LANG_SOURCE([[
         DB *db;
         
         db->set_errcall(db, error_callback_fn);
-        ], AC_MSG_RESULT(no),
+        ]])], AC_MSG_RESULT(no),
         AC_MSG_RESULT(yes)
         AC_DEFINE(HAVE_CONST_THIRD_PARAMETER_TO_DB_ERROR_CALLBACK, 1,
         Define if third param (message) to DB error callback function is const))
@@ -137,7 +140,7 @@ AC_DEFUN([AX_BERKELEY_DB],
     dnl while the txnid parameter is new.  So we don't test for the old
     dnl unknown parameter if we found the new one.
     AC_MSG_CHECKING(for DB stat with malloc function ptr)
-    AC_TRY_COMPILE([
+    AC_TRY_COMPILE([AC_LANG_SOURCE([[
       #include <db.h>
       #include <stdlib.h>
       ], [
@@ -147,7 +150,7 @@ AC_DEFUN([AX_BERKELEY_DB],
       u_int32_t flags = 0;
         
       ret = db->stat(db, &dummy, malloc, flags);
-      ], AC_MSG_RESULT(yes)
+      ]])], AC_MSG_RESULT(yes)
     AC_DEFINE(HAVE_UNKNOWN_PARAMETER_TO_DB_STAT, 1,
     Define if DB stat function takes malloc function ptr)
     have_db_stat_malloc=yes,
@@ -158,16 +161,16 @@ AC_DEFUN([AX_BERKELEY_DB],
     if test "x$have_db_stat_malloc" = "xno" ; then
     
        AC_MSG_CHECKING(for txnid parameter to DB stat function)
-       AC_TRY_COMPILE([
+       AC_TRY_COMPILE([AC_LANG_SOURCE([[
        #include <db.h>
-       ], [
+       ]])], [AC_LANG_SOURCE([[
        int ret = 0;
        DB *db = db;
        DB_TXN *txnid = txnid;
        u_int32_t flags = 0;
     
         ret = db->stat(db, txnid, NULL, flags);
-        ], AC_MSG_RESULT(yes)
+        ]])], AC_MSG_RESULT(yes)
         AC_DEFINE(HAVE_TXNID_PARAMETER_TO_DB_STAT, 1, 
         Define if DB stat function takes txnid parameter)
         have_txnid_param_to_stat=yes,
@@ -178,9 +181,9 @@ AC_DEFUN([AX_BERKELEY_DB],
     
     dnl Test to check for txnid parameter to DB open (DB4.1+)
     AC_MSG_CHECKING(for txnid parameter to DB open function)
-    AC_TRY_COMPILE([
+    AC_TRY_COMPILE([AC_LANG_SOURCE([[
     #include <db.h>
-    ], [
+    ]])], [AC_LANG_SOURCE([[
     int ret = 0;
     DB *db = NULL;
     DB_TXN *txnid = NULL;
@@ -191,7 +194,7 @@ AC_DEFUN([AX_BERKELEY_DB],
     int mode = 0;
     
     ret = db->open(db, txnid, file, database, type, flags, mode);
-    ], AC_MSG_RESULT(yes)
+    ]])], AC_MSG_RESULT(yes)
     AC_DEFINE(HAVE_TXNID_PARAMETER_TO_DB_OPEN, 1,
     Define if DB open function takes a txnid parameter),
     AC_MSG_RESULT(no))
@@ -208,26 +211,26 @@ AC_DEFUN([AX_BERKELEY_DB],
 
     dnl check for DB_BUFFER_SMALL (it is returned by dbp->get in db-4.4 and up)
     AC_MSG_CHECKING(for DB_BUFFER_SMALL error)
-    AC_TRY_COMPILE([
+    AC_TRY_COMPILE([AC_LANG_SOURCE([[
     #include <db.h>
-    ], [
+    ]])], [AC_LANG_SOURCE([[
     int res = DB_BUFFER_SMALL;
     res++;
-    ], AC_MSG_RESULT(yes)
+    ]])], AC_MSG_RESULT(yes)
     AC_DEFINE(HAVE_DB_BUFFER_SMALL, 1, [Define if db library has DB_BUFFER_SMALL error]),
     AC_MSG_RESULT(no))
 
     dnl Test to check for db->get_pagesize
     AC_MSG_CHECKING(for berkeley db get_pagesize function)
-    AC_TRY_COMPILE([
+    AC_TRY_COMPILE([AC_LANG_SOURCE([[
     #include <db.h>
-    ], [
+    ]])], [AC_LANG_SOURCE([[
     int ret = 0;
     DB *db = NULL;
     int pagesize;
     
     ret = db->get_pagesize(db, &pagesize);
-    ], AC_MSG_RESULT(yes)
+    ]])], AC_MSG_RESULT(yes)
     AC_DEFINE(HAVE_DB_GET_PAGESIZE, 1, [Define if DB has get_pagesize function]),
     AC_MSG_RESULT(no))
     
diff --git a/maint/config/openssl.m4 b/maint/config/openssl.m4
index 6bfb92e..d5400f5 100644
--- a/maint/config/openssl.m4
+++ b/maint/config/openssl.m4
@@ -15,13 +15,13 @@ AC_DEFUN([AX_OPENSSL],
         LIBS="$LIBS -lcrypto -lssl"
     
         AC_COMPILE_IFELSE(
-    	    [#include "openssl/bio.h"],
+    	    [AC_LANG_SOURCE([[#include "openssl/bio.h"]])],
     	    [],
     	    [AC_MSG_ERROR(Invalid openssl path specified.  No openssl/bio.h found.)])
     
         AC_TRY_LINK(
-    	    [#include "openssl/bio.h"],
-    	    [BIO * b;],
+    	    [AC_LANG_SOURCE([[#include "openssl/bio.h"]])],
+    	    [AC_LANG_SOURCE([[BIO * b;]])],
     	    [AC_MSG_RESULT(yes)],
     	    [AC_MSG_ERROR(could not find openssl libs)])
     
@@ -39,13 +39,13 @@ AC_DEFUN([AX_OPENSSL_OPTIONAL],
     LIBS="$LIBS -lcrypto -lssl"
 
     AC_COMPILE_IFELSE(
-      [#include "openssl/bio.h"],
+      [AC_LANG_SOURCE([[#include "openssl/bio.h"]])],
       [],
       [AC_MSG_WARN(No openssl headers found.)])
 
     AC_TRY_LINK(
-      [#include "openssl/bio.h"],
-      [BIO * b;],
+      [AC_LANG_SOURCE([[#include "openssl/bio.h"]])],
+      [AC_LANG_SOURCE([[BIO * b;]])],
       [AC_MSG_RESULT(yes)
        AC_DEFINE(WITH_OPENSSL, 1, [Define if openssl exists])
       ],