Re: parted: FTBFS : probably due to new glibc and 2.6.0-test linux kernel headers.

[Sven Luther <sven.luther@wanadoo.fr>]

On Mon, Nov 03, 2003 at 02:23:46PM -0500, Daniel Jacobowitz wrote:
> On Mon, Nov 03, 2003 at 08:00:37PM +0100, Sven Luther wrote:
> > On Mon, Nov 03, 2003 at 06:39:19PM +0100, Sven Luther wrote:
> > > Subject: parted: FTBFS : probably due to new glibc and 2.6.0-test linux kernel headers.
> > > Package: parted
> > > Version: 1.6.6-1.1
> > > Severity: important
> > > Justification: fails to build from source
> > > 
> > > i386-linux-gcc -DHAVE_CONFIG_H -I. -I../../libparted -I..  -I../../include -g -O2 -D_REENTRANT -D_FILE_OFFSET_BITS=64 -DLOCALEDIR=\"/usr/share/locale\" -DLOCALEDIR=\"/usr/share/locale\" -W -Wall -Wno-unused -Wno-switch -Wno-format -Werror -c
> > > ../../libparted/linux.c  -fPIC -DPIC -o .libs/linux.lo
> > > ../../libparted/linux.c: In function `_device_get_length':
> > > ../../libparted/linux.c:407: error: parse error before '[' token
> > > ../../libparted/linux.c:407: warning: signed and unsigned type in conditional expression
> > > 
> > > It used to build a few days ago, but this may be due to the new glibc
> > > which just did enter unstable, and the kernel headers that go with it, i
> > > will investigate.
> > 
> > The problem comes from /usr/include/linux/fs.h and the :
> > 
> >   #define BLKGETSIZE64 _IOR(0x12,114,size_t)      /* return device size in bytes (u64 *arg) */
> > 
> > Definition, which in turn expands in /usr/include/asm/ioctl.h to :
> > 
> >   #define _IOR(type,nr,size) _IOC(_IOC_READ,(type),(nr),(_IOC_TYPECHECK(size)))
> > 
> > And in the same file, we see that _IOC_TYPECHECK(size) is :
> > 
> >   /* provoke compile error for invalid uses of size argument */
> >   extern int __invalid_size_argument_for_IOC;
> >   #define _IOC_TYPECHECK(t) \
> >          ((sizeof(t) == sizeof(t[1]) && \
> > 	   sizeof(t) < (1 << _IOC_SIZEBITS)) ? \
> > 	   sizeof(t) : __invalid_size_argument_for_IOC)
> > 
> > BLKGETSIZE64 is used in libparted/linux.c as : 
> > 
> >   ioctl(arch_specific->fd, BLKGETSIZE64, &bytes)
> > 
> > I am a bit at a loss on how to solve this problem though. I guess it is
> > trying to do a sizeof(size_t[1]) which is the cause of the first
> > problem, and that it is trying to compare sizeof(t) with (1 << _IOC_SIZEBITS)
> > which is the cause of the second error. Or maybe the second error is
> > because the result of sizeof(t) is unsigned while
> > __invalid_size_argument_for_IOC is not.
> 
> This macro is there to ensure that people don't use size_t, I thought. 
> I'd have to read the discussion on LKML again though.

Mmm, so why is size_t used in linux/fs.h then ?

Friendly,

Sven Luther