[17/17] genksyms: fix syntax error for attribute before init-declarator

Commit Message

Masahiro Yamada Jan. 13, 2025, 3 p.m. UTC

A longstanding issue with genksyms is that it has hidden syntax errors.

For example, genksyms fails to parse the following valid code:

    int x, __attribute__((__section__(".init.data")))y;

Here, only 'y' is annotated by the attribute, although I am not aware
of actual uses of this pattern in the kernel tree.

When a syntax error occurs, yyerror() is called. However,
error_with_pos() is a no-op unless the -w option is provided.

You can observe syntax errors by manually passing the -w option.

    $ echo 'int x, __attribute__((__section__(".init.data")))y;' | scripts/genksyms/genksyms -w
    <stdin>:1: syntax error

This commit allows attributes to be placed between a comma and
init_declarator.

Signed-off-by: Masahiro Yamada <[e-mail]>
---

 scripts/genksyms/parse.y | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

Patch

diff --git a/scripts/genksyms/parse.y b/scripts/genksyms/parse.y
index a2cd035a78c9..ee600a804fa1 100644
--- a/scripts/genksyms/parse.y
+++ b/scripts/genksyms/parse.y
@@ -173,9 +173,9 @@  init_declarator_list:
 		  $$ = $1;
 		  dont_want_type_specifier = true;
 		}
-	| init_declarator_list ',' init_declarator
-		{ struct string_list *decl = *$3;
-		  *$3 = NULL;
+	| init_declarator_list ',' attribute_opt init_declarator
+		{ struct string_list *decl = *$4;
+		  *$4 = NULL;
 		  free_list(*$2, NULL);
 		  *$2 = decl_spec;
 
@@ -186,7 +186,7 @@  init_declarator_list:
 		  add_symbol(current_name,
 			     is_typedef ? SYM_TYPEDEF : SYM_NORMAL, decl, is_extern);
 		  current_name = NULL;
-		  $$ = $3;
+		  $$ = $4;
 		  dont_want_type_specifier = true;
 		}
 	;