Mime-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
To: "Eric Gillespie (Root)" <root AT flying-brick DOT caverock DOT net DOT nz>,
        djgpp AT delorie DOT com
From: Nate Eldredge <nate AT cartsys DOT com>
Subject: Re: Newbie question: multiple #include statements
Date: Fri, 10 Apr 1998 18:49:47 -0700
Message-ID: <19980411014943.AAA28260@ppp127.cartsys.com>
Precedence: bulk

At 08:23  4/10/1998 +1300, Eric Gillespie (Root) wrote:

>> Some compilers may create an interim file consisting of
>>tokens from multiple include files (more compact and efficient than
>>parsing an ASCII file), for use by different source modules.  For
>>example, if you have more than one ".c" file that includes "string.h",
>>some compilers may precompile this header file.
>
>A quick question - what support is there in gcc for this above mentioned idea?

None.

>And where would the gcc compiler store the pre-compiled headers?

Wherever the authors thought was a good idea, I guess.

>Would the compilation be permanent, or only pre-compiled for each gcc session?

It's permanent, else there's little point. Headers are typically made
idempotent, so that a second inclusion on the same file doesn't actually do
anything. Thus a header is almost never compiled more than once for a given
gcc invocation.

Nate Eldredge
nate AT cartsys DOT com