[PATCH] Always pass an open file descriptor to c_common_read_pch

[Zack Weinberg]

Ritzert@t-online.de writes:

>         * c-pch.c (c_common_read_pch): Assert that an invalid file descriptor
>         will never get here.
>         * cppfiles.c (should_stack_file): Make sure that the file descriptor
>         passed to read_pch is valid.
...

> !
> !   my_friendly_assert( fd != -1, 20030818 );

my_friendly_assert is not to be used in new code.  Write

  if (fd == -1)
    abort ();

instead.  Actually, I don't think this assertion is necessary; the
fatal error after fdopen fails is good enough.

> Index: cppfiles.c
> ===================================================================
> RCS file: /cvs/gcc/gcc/gcc/cppfiles.c,v
> retrieving revision 1.186
> diff -u -3 -p -f -r1.186 cppfiles.c
> *** cppfiles.c  9 Aug 2003 22:14:07 -0000       1.186
> --- cppfiles.c  18 Aug 2003 19:39:42 -0000
> *************** should_stack_file (cpp_reader *pfile, _c
> *** 551,556 ****
> --- 551,563 ----
>     /* Handle PCH files immediately; don't stack them.  */
>     if (include_pch_p (file))
>       {
> +       /* Make sure the file is open.  */
> +       if (file->fd == -1)
> +       {
> +         if (!pch_open_file (pfile, file))
> +           return false;
> +       }
> +
>         pfile->cb.read_pch (pfile, file->path, file->fd,
> file->pchname);
>         close (file->fd);
>         file->fd = -1;

I don't think this is right either.  Your test case does not involve
PCH; we should not be going through this code path at all.

zw