precompiled header support

[Dave Korn]

> -----Original Message-----
> From: gcc-owner On Behalf Of Gunther Nikl
> Sent: 07 May 2004 13:26

> Hello!
> 
> What host capabilites are required to use precompiled 
> headers? The sources
> seem to imply that mmap() is required to load a PCH to fixed 
> address. What
> happens if a host doesn't support mmap? To which address the 
> PCH will be
> loaded?

  Some arbitrary one, and then gcc crashes when trying to use it, according
to earlier discussion on this list.  See 

http://www.google.com/search?hl=en&ie=UTF-8&oe=UTF-8&q=pch+exec-shield+site%
3Agcc.gnu.org

for the mailing list archive of the thread.

  Which led me to the following thought: can't the gc be (ab)used to chase
down all the pointers in the mmap'd area and convert them to a self-relative
form?

> Is it possible to disable generating/using precompiled 
> headers for hosts
> that don't support it?

  Simply don't compile your header files.  Gcc won't force it on you.

    cheers, 
      DaveK
-- 
Can't think of a witty .sigline today....