[Cocci] Exception "try to delete an expanded token: {" and C macros

[riccardo.lucchese@gmail.com (Riccardo Lucchese)]

On Tue, Jul 22, 2014 at 06:17:10PM +0200, Julia Lawall wrote:
> 
> 
> On Tue, 22 Jul 2014, Riccardo Lucchese wrote:
> 
> > Hello,
> >
> > Running the command (semantic patch is attached)
> >
> > $ spatch --sp-file macro-err.cocci --dir drivers/staging/octeon-usb/octeon-hcd.c
> >
> > from the root dir of linux-next-20140721, yields the following error:
> >
> > init_defs_builtins: /usr/local/share/coccinelle/standard.h
> > HANDLING: drivers/staging/octeon-usb/octeon-hcd.c
> > Fatal error: exception Failure("drivers/staging/octeon-usb/octeon-hcd.c: 429: try to delete an expanded token: {")
> >
> >
> > The code around where the exception happens (--->) reads:
> >
> > /* This macro spins on a field waiting for it to reach a value */
> > #define CVMX_WAIT_FOR_FIELD32(address, type, field, op, value, timeout_usec)\
> > --->    ({int result;                                                       \
> >         do {                                                                \
> >                 uint64_t done = cvmx_get_cycle() + (uint64_t)timeout_usec * \
> >                         octeon_get_clock_rate() / 1000000;                  \
> >                 type c;                                                     \
> >                 while (1) {                                                 \
> >                         c.u32 = __cvmx_usb_read_csr32(usb, address);        \
> >                         if (c.s.field op (value)) {                         \
> >                                 result = 0;                                 \
> >                                 break;                                      \
> >                         } else if (cvmx_get_cycle() > done) {               \
> >                                 result = -1;                                \
> >                                 break;                                      \
> >                         } else                                              \
> >                                 cvmx_wait(100);                             \
> >                 }                                                           \
> >         } while (0);                                                        \
> >         result; })
> >
> >
> > Should I change something in my invocation to deal with this macro ?
> 
> One solution is to add the following command-line argument:
> --disable-multi-pass
> 
> Then it will not try to take macros into account on a parse failure.  But
> there may be other macros whose definitions do need to be taken into
> account to get parsing to succeed.
> 
> Another option is to extend standard.h with
> 
> #define CVMX_WAIT_FOR_FIELD32(a,b,c,d,e,f)
> 
> and then give the resulting file with the argument --macro-file-builtins.
> That will make it use your standard.h definition before it tries the real
> definition.
> 
> julia

I see. Thanks !

riccardo