The workaround is to add the size argument to the access
attribute.
[[gnu::access(write_only, 2, 1)]]
int f(int n, char * a[n]);
int f(int n, char * a[n]);
Martin
Am Samstag, dem 14.12.2024 um 08:14 +0100 schrieb Martin Uecker:
> Yes, there are two bugs. The first with
>
> [[gnu::access(write_only, 2)]]
> int f(int n, char * a[n]);
>
>
> And the second with -Wvla-parameter -Wno-attributes
>
> [[gnu::access(write_only, 2)]]
> int f(int n, char * a[n]);
> int f(int n, char * a[n]);
>
> Can you file two bugs? (if those don't exist yet)
>
> Martin
>
>
> Am Samstag, dem 14.12.2024 um 00:03 +0100 schrieb Alejandro Colomar:
> > Hi,
> >
> > The diagnostic for the attribute directive ignored was due to an old GCC
> > version. However, I'm still seeing diagnostics that I think don't make
> > sense, with GCC 14.
> >
> > I think this is a compiler bug (or two), maybe?
> >
> > This seems to relate to array parameters; CC += Martin.
> >
> > Cheers,
> > Alex
> >
> > alx@www:/tmp$ cat str.c
> > #include <errno.h>
> > #include <stddef.h>
> > #include <string.h>
> > #include <sys/types.h>
> >
> > [[gnu::access(read_write, 1)]]
> > [[gnu::access(write_only, 4)]]
> > [[gnu::null_terminated_string_arg(1)]]
> > [[gnu::null_terminated_string_arg(2)]]
> > inline ssize_t strsep2arr(char *s, const char *restrict delim,
> > size_t n, char *a[restrict n]);
> >
> > // strsep(3) a string into an array of strings.
> > // Return the number of fields in the string, or -1 on error.
> > inline ssize_t strsep2arr(char *s, const char *restrict delim,
> > size_t n, char *a[restrict n])
> > {
> > size_t i;
> >
> > for (i = 0; i < n && s != NULL; i++)
> > a[i] = strsep(&s, delim);
> >
> > if (s != NULL) {
> > errno = E2BIG;
> > return -1;
> > }
> >
> > return i;
> > }
> >
> > alx@www:/tmp$ gcc -Wall -Wextra -S str.c
> > str.c:10:16: warning: attribute ‘access (write_only, 4)’ positional argument 2 missing in previous designation [-Wattributes]
> > 10 | inline ssize_t strsep2arr(char *s, const char *restrict delim,
> > | ^~~~~~~~~~
> > str.c:11:12: note: designating the bound of variable length array argument 4
> > 11 | size_t n, char *a[restrict n]);
> > | ~~~~~~~^ ~~~~~~~~~~~~~~~~~~~
> > str.c:16:21: warning: argument 4 of type ‘char *[restrict n]’ declared as a variable length array [-Wvla-parameter]
> > 16 | size_t n, char *a[restrict n])
> > | ~~~~~~^~~~~~~~~~~~~
> > str.c:11:21: note: previously declared as an ordinary array ‘char *[restrict]’
> > 11 | size_t n, char *a[restrict n]);
> > | ~~~~~~^~~~~~~~~~~~~
> > str.c: In function ‘strsep2arr’:
> > str.c:15:16: warning: attribute ‘access (write_only, 4)’ positional argument 2 missing in previous designation [-Wattributes]
> > 15 | inline ssize_t strsep2arr(char *s, const char *restrict delim,
> > | ^~~~~~~~~~
> > str.c:16:12: note: designating the bound of variable length array argument 4
> > 11 | size_t n, char *a[restrict n]);
> > | ~~~~~~~~~~~~~~~~~~~
> > ......
> > 16 | size_t n, char *a[restrict n])
> > | ~~~~~~~^
> > alx@www:/tmp$ gcc --version
> > gcc (Debian 14.2.0-8) 14.2.0
> > Copyright (C) 2024 Free Software Foundation, Inc.
> > This is free software; see the source for copying conditions. There is NO
> > warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
> >
> >
> >
> >
>
