Re: iPhone Platform Compiler Symbol?
Re: iPhone Platform Compiler Symbol?
- Subject: Re: iPhone Platform Compiler Symbol?
- From: Philip Aker <email@hidden>
- Date: Thu, 14 May 2009 19:14:29 -0700
On 2009-05-14, at 18:18:14, Gwynne Raskind wrote:
On May 14, 2009, at 8:54 PM, Philip Aker wrote:
# gcc -dM -E -x c /dev/null > gccdefs.txt
and
# cpp -dM < /dev/null > cppdefs.txt
Show no difference in the output files.
I think cpp is currently a call through to gcc so theoretically
they should always produce the same set of defines given equivalent
options.
True or false?
True, though the whole story is slightly more complicated. A little
fiddling about with the -v flag actually shows the following:
1. cpp is a wrapper for gcc-4.0 -E
2. gcc-4.0 -E in turn calls through to cc1 -E -traditional-cpp
3. cpp-4.2 and gcc-4.2 call through to cc1 -E
On 2009-05-14, at 18:38:58, Peter O'Gorman wrote:
At the risk of really annoying Chris...
/usr/bin/cpp is a shell script that does indeed end up calling
/usr/bin/gcc -E -x c, the differences are, cpp does not take -arch
flags
(well, it happily takes the -arch flag, but thinks the argument is a
file), and does not do languages other than c, and, in this case, does
not call a completely different cross-compiler.
Thanks for the fine print Gwynne, and Peter. That's what I wanted to
get out of the sidebar of the thread.
Anyway, Availability.h really is the right answer.
I hope K. Chen has seen CDE's posts by now.
Philip Aker
echo email@hidden@nl | tr a-z@. p-za-o.@
Democracy: Two wolves and a sheep voting on lunch.
_______________________________________________
Do not post admin requests to the list. They will be ignored.
Xcode-users mailing list (email@hidden)
Help/Unsubscribe/Update your Subscription:
This email sent to email@hidden