How to make c++ realize empty character constant ''?

Brandon Allbery allbery.b at
Mon Dec 9 06:52:49 PST 2013

On Sun, Dec 8, 2013 at 1:35 PM, Gmail <yangzf01 at> wrote:
> I am trying to compile the following statements using CPP.

This is a (formerly common) abuse of CPP and nobody can guarantee the
result. I *very strongly* recommend you contact whoever provided whatever
it is you are working with and get them to stop using cpp.

The message you got was a warning, not an error. This warning can be
suppressed (add parameters: -Wno-invalid-pp-token -Wno-unicode
-Wno-trigraphs) but very little can be done if clang's cpp is producing
output you don't expect.

Worst case you can try making a gcc the user default compiler:

sudo port install gcc48 && sudo port select --set gcc mp-gcc48

and then find and run its cpp. I can't guarantee future versions of gcc
will continue to work, though, as there is no guarantee whatsoever that cpp
will work on things that are not C/C++.

brandon s allbery kf8nh                               sine nomine associates
allbery.b at                                  ballbery at
unix, openafs, kerberos, infrastructure, xmonad
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