diff --git a/ext/intl/config.w32 b/ext/intl/config.w32
index ab7dc42b66246..dec7180e62174 100644
--- a/ext/intl/config.w32
+++ b/ext/intl/config.w32
@@ -126,7 +126,6 @@ if (PHP_INTL != "no") {
 		}
 
 		ADD_FLAG("CFLAGS_INTL", "/EHsc /DUNISTR_FROM_CHAR_EXPLICIT=explicit /DUNISTR_FROM_STRING_EXPLICIT=explicit /DU_NO_DEFAULT_INCLUDE_UTF_HEADERS=1 /DU_HIDE_OBSOLETE_UTF_OLD_H=1");
-		AC_DEFINE("HAVE_INTL", 1, "Internationalization support enabled");
 	} else {
 		WARNING("intl not enabled; libraries and/or headers not found");
 	}
diff --git a/ext/pdo_dblib/config.m4 b/ext/pdo_dblib/config.m4
index 694c44c7e7ab2..993ca3d6033af 100644
--- a/ext/pdo_dblib/config.m4
+++ b/ext/pdo_dblib/config.m4
@@ -45,7 +45,6 @@ if test "$PHP_PDO_DBLIB" != "no"; then
 
   PDO_DBLIB_DEFS="-DPDO_DBLIB_FLAVOUR=\\\"freetds\\\""
   PHP_NEW_EXTENSION(pdo_dblib, pdo_dblib.c dblib_driver.c dblib_stmt.c, $ext_shared,,-I$pdo_cv_inc_path $PDO_DBLIB_DEFS -DZEND_ENABLE_STATIC_TSRMLS_CACHE=1)
-  AC_DEFINE(HAVE_PDO_DBLIB,1,[ ])
   PHP_SUBST(PDO_DBLIB_SHARED_LIBADD)
 
   PHP_ADD_EXTENSION_DEP(pdo_dblib, pdo)
diff --git a/ext/pdo_firebird/config.m4 b/ext/pdo_firebird/config.m4
index 594e7c220ecf1..d4a245d5a904b 100644
--- a/ext/pdo_firebird/config.m4
+++ b/ext/pdo_firebird/config.m4
@@ -60,7 +60,6 @@ if test "$PHP_PDO_FIREBIRD" != "no"; then
 
   PHP_CHECK_PDO_INCLUDES
 
-  AC_DEFINE(HAVE_PDO_FIREBIRD,1,[ ])
   PHP_NEW_EXTENSION(pdo_firebird, pdo_firebird.c firebird_driver.c firebird_statement.c, $ext_shared,,-I$pdo_cv_inc_path)
   PHP_SUBST(PDO_FIREBIRD_SHARED_LIBADD)
   PHP_ADD_EXTENSION_DEP(pdo_firebird, pdo)
diff --git a/ext/tokenizer/config.w32 b/ext/tokenizer/config.w32
index ee98c0cc138a4..5d933c3c31b77 100644
--- a/ext/tokenizer/config.w32
+++ b/ext/tokenizer/config.w32
@@ -4,5 +4,4 @@ ARG_ENABLE("tokenizer", "tokenizer support", "yes");
 
 if (PHP_TOKENIZER == "yes") {
 	EXTENSION("tokenizer", "tokenizer.c tokenizer_data.c");
-	AC_DEFINE("HAVE_TOKENIZER", 1, "Tokenizer support");
 }