Re: other/10777: gcc: unrecognized option `-no-cpp-precomp'

[Dara Hazeghi <dhazeghi@yahoo.com>]

The following reply was made to PR other/10777; it has been noted by GNATS.

From: Dara Hazeghi <dhazeghi@yahoo.com>
To: shrao@nyx.net, gcc-gnats@gcc.gnu.org, nobody@gcc.gnu.org
Cc:  
Subject: Re: other/10777: gcc: unrecognized option `-no-cpp-precomp'
Date: Wed, 14 May 2003 00:34:02 -0700

 http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view%20audit- 
 trail&database=gcc&pr=10777
 
 Hello,
 
 first, before you e-mail the gcc release manager, you should at least  
 send a message to gcc-bugs@gcc.gnu.org. Mark is responsible for seeing  
 that the releases get out, not for all the problems in gcc. That's why  
 we have a bugs mailing list.
 
 Second, the reason for this behavior is fairly simple. Apple's gcc has  
 something called cpp-precomp which was their old method of precompiled  
 headers. Official gcc releases don't have this option (it is an Apple  
 specific thing, and will be going away soon, since it's now obsolete).
 
 We disable it when building gcc because it has a number of bugs which  
 may cause compilation to fail. Because 99% of the people building gcc  
 on MacOS X will be building it with Apple's gcc, we need to disable  
 cpp-precomp to prevent the builds from failing.
 
 Unfortunately, as seen in your case, because we assume Apple gcc is the  
 compiler being used to build gcc on MacOS X, we assume this option to  
 disable cpp-precomp is available. In your case, to get rid of the  
 warnings, all you have to do is set the CFLAGS environment variable to  
 -O2 -g, ie do setenv CFLAGS "-O2 -g"  before building gcc, and this  
 warning should go away. Hopefully we can come up with a way to automate  
 this in the future.
 
 Dara