Re: [Qemu-devel] [PATCH 12/14] linux-user/mmap.c: fix warnings with _FORTIFY_SOURCE

[Rtp]

"Kirill A. Shutemov" <address@hidden> writes:

Hi,

>   CC    i386-linux-user/mmap.o
> cc1: warnings being treated as errors
> /usr/src/RPM/BUILD/qemu-0.11.92/linux-user/mmap.c: In function 'mmap_frag':
> /usr/src/RPM/BUILD/qemu-0.11.92/linux-user/mmap.c:253: error: ignoring return 
> value of 'pread', declared with attribute warn_unused_result
> /usr/src/RPM/BUILD/qemu-0.11.92/linux-user/mmap.c: In function 'target_mmap':
> /usr/src/RPM/BUILD/qemu-0.11.92/linux-user/mmap.c:477: error: ignoring return 
> value of 'pread', declared with attribute warn_unused_result
> make[1]: *** [mmap.o] Error 1
>
> Signed-off-by: Kirill A. Shutemov <address@hidden>
> ---
>  linux-user/mmap.c |    6 ++++--
>  1 files changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/linux-user/mmap.c b/linux-user/mmap.c
> index 144fb7c..e496c64 100644
> --- a/linux-user/mmap.c
> +++ b/linux-user/mmap.c
> @@ -250,7 +250,8 @@ static int mmap_frag(abi_ulong real_start,
>              mprotect(host_start, qemu_host_page_size, prot1 | PROT_WRITE);
>  
>          /* read the corresponding file data */
> -        pread(fd, g2h(start), end - start, offset);
> +        if (pread(fd, g2h(start), end - start, offset) == -1)
> +            return -errno;

This needs to be checked but iirc, it's wrong. One should set errno and
return -1. Please double check and fix if needed.

Thanks,
Arnaud