Re: fixincl on linux systems

[Bruce Korb <bkorb at cruzio dot com>]

Andi Kleen wrote:
> 
> The main problem is that it destroys package management on linux systems.

Fair enough.

> A lot of rpms put include files into /usr/include which sometimes fixincl
> likes to fix up (mostly for relatively silly things like // -> /* */ comments
> that do not affect usability with gcc -- include files on linux systems
> tend to work with gcc)

Many months ago that was fixed by allowing // comments in system
headers.
fixincl no longer makes that change.  I will send you under separate
cover
a tarball of the current gcc/fixinc directory.  It ought to be a drop-in
replacement for whatever you are working with.  Let me know what your
resulting
issues are.

Here is one I have:  OpenServer 5 comes with an include subdirectory:

   /usr/include/oldstyle

wherein the K&R style of headers reside.  Needless to say, a lot of
the headers are fixed.  But it is pointless to do so.  They are never
(or should never be) seen by the ANSI/ISO/C9x flavor of C compiler.
Therefore, it would be good to omit them from fixinc processing.
I propose an addition to the platform specific headers that, when
defined, provides a file name pattern for fixincl to ignore.  For
OSr5, that would be "oldstyle/.*".  For Linux, alas, that would *not*
be ".*".  At least, not unconditionally.  It would have to depend
upon the version of libc because it, occasionally, has bugs, too.

Perhaps along the lines of:

  #if libc-is-newer-than-some-threshhold
  #  define  FIXINC_BYPASS_PATTERN  ".*"
  #endif

> I end up with lots of private copies of include files in the gcc directory
> after a build. When the rpm is updated later the private copy isn't.

That would be solvable if fix-headers and fixincl were a single,
separable
process.  You cannot just install "fixincl" and rerun it because of what
fix-headers does later  :-(.

> Now when the interface of a library in the rpm changed accessing it with older
> include files usually leads to miscompiled programs.
> 
> My current solution is to simply rm -rf the files after install, but not
> generating them in the first time would be better and faster.
> 
> I would appreciate it if you could consider a --disable-fixincl switch.

I hate command line switches that are always used in one context
and never used in another.  Better to have the context be queried about
or provide the information, as I have suggested above.

 - Bruce