diff --git a/scripts/genksyms/keywords.gperf b/scripts/genksyms/keywords.gperf
index c75e0c8d8f0c..5ef3733225fb 100644
--- a/scripts/genksyms/keywords.gperf
+++ b/scripts/genksyms/keywords.gperf
@@ -11,6 +11,7 @@ __attribute, ATTRIBUTE_KEYW
 __attribute__, ATTRIBUTE_KEYW
 __const, CONST_KEYW
 __const__, CONST_KEYW
+__extension__, EXTENSION_KEYW
 __inline, INLINE_KEYW
 __inline__, INLINE_KEYW
 __signed, SIGNED_KEYW
diff --git a/scripts/genksyms/parse.y b/scripts/genksyms/parse.y
index ca04c944b7c3..408cdf82b271 100644
--- a/scripts/genksyms/parse.y
+++ b/scripts/genksyms/parse.y
@@ -61,6 +61,7 @@ remove_list(struct string_list **pb, struct string_list **pe)
 %token DOUBLE_KEYW
 %token ENUM_KEYW
 %token EXTERN_KEYW
+%token EXTENSION_KEYW
 %token FLOAT_KEYW
 %token INLINE_KEYW
 %token INT_KEYW
@@ -110,7 +111,9 @@ declaration:
 	;
 
 declaration1:
-	TYPEDEF_KEYW { is_typedef = 1; } simple_declaration
+	EXTENSION_KEYW TYPEDEF_KEYW { is_typedef = 1; } simple_declaration
+		{ $$ = $4; }
+	| TYPEDEF_KEYW { is_typedef = 1; } simple_declaration
 		{ $$ = $3; }
 	| simple_declaration
 	| function_definition