diff --git a/src/libstrongswan/settings/settings_lexer.l b/src/libstrongswan/settings/settings_lexer.l
index e8c2b9884..cd9b5ff5e 100644
--- a/src/libstrongswan/settings/settings_lexer.l
+++ b/src/libstrongswan/settings/settings_lexer.l
@@ -37,8 +37,8 @@ static void include_files(parser_helper_t *ctx);
 /* due to that disable interactive mode, which requires isatty() */
 %option never-interactive
 
-/* don't use global variables, and interact properly with bison */
-%option reentrant bison-bridge
+/* don't use global variables */
+%option reentrant
 
 /* maintain the line number */
 %option yylineno
diff --git a/src/libstrongswan/settings/settings_parser.y b/src/libstrongswan/settings/settings_parser.y
index cc1c91775..a541e6b9c 100644
--- a/src/libstrongswan/settings/settings_parser.y
+++ b/src/libstrongswan/settings/settings_parser.y
@@ -55,20 +55,27 @@ static void add_references(parser_helper_t *ctx, array_t *references);
  * Make sure to call lexer with the proper context
  */
 #undef yylex
-static int yylex(YYSTYPE *lvalp, parser_helper_t *ctx)
+static int yylex(SETTINGS_PARSER_STYPE *yylval, parser_helper_t *ctx)
 {
-	return settings_parser_lex(lvalp, ctx->scanner);
+	return settings_parser_lex(yylval, ctx->scanner);
 }
 
 %}
 %debug
 
 /* generate verbose error messages */
-%error-verbose
+%define parse.error verbose
 /* generate a reentrant parser */
 %define api.pure
 /* prefix function/variable declarations */
-%name-prefix "settings_parser_"
+%define api.prefix {settings_parser_}
+/* make sure flex uses the right definition */
+%code provides
+{
+	#define YY_DECL \
+		int settings_parser_lex(SETTINGS_PARSER_STYPE *yylval, void *yyscanner)
+	YY_DECL;
+}
 
 /* interact properly with the reentrant lexer */
 %lex-param {parser_helper_t *ctx}
diff --git a/src/starter/parser/lexer.l b/src/starter/parser/lexer.l
index 1faec953e..c856af77d 100644
--- a/src/starter/parser/lexer.l
+++ b/src/starter/parser/lexer.l
@@ -38,8 +38,8 @@ static void include_files(parser_helper_t *ctx);
 /* due to that disable interactive mode, which requires isatty() */
 %option never-interactive
 
-/* don't use global variables, and interact properly with bison */
-%option reentrant bison-bridge
+/* don't use global variables */
+%option reentrant
 
 /* maintain the line number */
 %option yylineno
diff --git a/src/starter/parser/parser.y b/src/starter/parser/parser.y
index 1371fe931..09325d975 100644
--- a/src/starter/parser/parser.y
+++ b/src/starter/parser/parser.y
@@ -48,20 +48,27 @@ static void conf_parser_error(parser_helper_t *ctx, const char *s);
  * Make sure to call lexer with the proper context
  */
 #undef yylex
-static int yylex(YYSTYPE *lvalp, parser_helper_t *ctx)
+static int yylex(CONF_PARSER_STYPE *yylval, parser_helper_t *ctx)
 {
-	return conf_parser_lex(lvalp, ctx->scanner);
+	return conf_parser_lex(yylval, ctx->scanner);
 }
 
 %}
 %debug
 
 /* generate verbose error messages */
-%error-verbose
+%define parse.error verbose
 /* generate a reentrant parser */
 %define api.pure
 /* prefix function/variable declarations */
-%name-prefix "conf_parser_"
+%define api.prefix {conf_parser_}
+/* make sure flex uses the right definition */
+%code provides
+{
+	#define YY_DECL \
+		int conf_parser_lex(CONF_PARSER_STYPE *yylval, void *yyscanner)
+	YY_DECL;
+}
 
 /* interact properly with the reentrant lexer */
 %lex-param {parser_helper_t *ctx}