Author: Keisuke Nishimura
Revision Date: 2021-04-03 14:00:06 UTC

parsing_cocci: ast0: Add support for __attribute__ with one argument

This series adds support for __attribute__ with one argument.

Current Coccinelle is having a problem with attrs and endattrs in C
parser.
Here is an example of AST for C.
 #1
struct { int i;} __attr;

attrs = []
endattrs = [ __attr]

 #2
struct { int i;} __attribute__((pack));

attrs = [__attribute__((pack))]
endattrs = []

__attribute__((pack)) in #2 should be interpreted as attrs.

This problem results from the implementation of parsing_c/parser_c.mly
and parsing_c/parsing_hacks.ml.

The current implementation in parsing_hacks.ml only checks the next
couple of tokens and whether it can match some regular expressions to
replace a specific token type for another token type. (e.g. regarding
endattrs, Coccinelle will check "^__.*$" and whether the next token is
";" or "=" etc..., and replace TIdent for TMacroEndAttr).
And parser_c.mly attempt to create AST based on the token processed
by parsing_hacks.ml.

To solve this problem, the algorithm used in current parsing_hacks.ml
needs to be revised totally. Maybe we can also solve it by changing
parser_c.mly. But it requires more complex works and a lot of time.

Signed-off-by: Keisuke Nishimura <mumumu0722@gmail.com>