A longstanding issue with genksyms is that it has hidden syntax errors.
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.
For example, with CONFIG_MODVERSIONS=y on v6.13-rc1:
$ make -s KCFLAGS=-D__GENKSYMS__ init/main.i
$ cat init/main.i | scripts/genksyms/genksyms -w
[ snip ]
./include/linux/efi.h:1225: syntax error
The syntax error occurs in the following code in include/linux/efi.h:
efi_status_t
efi_call_acpi_prm_handler(efi_status_t (__efiapi *handler_addr)(u64, void *),
u64 param_buffer_addr, void *context);
The issue arises from __efiapi, which is defined as either
__attribute__((ms_abi)) or __attribute__((regparm(0))).
This commit allows abstract_declarator to be prefixed with attributes.
To avoid conflicts, I tweaked the rule for decl_specifier_seq. Due to
this change, a standalone attribute cannot become decl_specifier_seq.
Otherwise, I do not know how to resolve the conflicts.
The following code, which was previously accepted by genksyms, will now
result in a syntax error:
void my_func(__attribute__((unused))x);
I do not think it is a big deal because GCC also fails to parse it.
$ echo 'void my_func(__attribute__((unused))x);' | gcc -c -x c -
<stdin>:1:37: error: unknown type name 'x'
Signed-off-by: Masahiro Yamada <masahiroy@xxxxxxxxxx>
---
scripts/genksyms/parse.y | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/scripts/genksyms/parse.y b/scripts/genksyms/parse.y
index cd933a95548d..54e16c2e0b4b 100644
--- a/scripts/genksyms/parse.y
+++ b/scripts/genksyms/parse.y
@@ -203,8 +203,9 @@ decl_specifier_seq_opt:
;
decl_specifier_seq:
- decl_specifier { decl_spec = *$1; }
+ attribute_opt decl_specifier { decl_spec = *$2; }
| decl_specifier_seq decl_specifier { decl_spec = *$2; }
+ | decl_specifier_seq ATTRIBUTE_PHRASE { decl_spec = *$2; }
;
decl_specifier:
@@ -216,7 +217,6 @@ decl_specifier:
}
| type_specifier { dont_want_type_specifier = true; $$ = $1; }
| type_qualifier
- | ATTRIBUTE_PHRASE
;
storage_class_specifier:
@@ -406,8 +406,8 @@ direct_abstract_declarator1:
{ $$ = $4; }
| direct_abstract_declarator1 BRACKET_PHRASE
{ $$ = $2; }
- | open_paren abstract_declarator ')'
- { $$ = $3; }
+ | open_paren attribute_opt abstract_declarator ')'
+ { $$ = $4; }
| open_paren error ')'
{ $$ = $3; }
| BRACKET_PHRASE
--
2.43.0
