On Wed, Feb 10, 2016 at 05:27:46PM +0100, Tomáš Smetana wrote: > Hello, > one of my packages (tvtime) failed to build during the mass rebuild. Not a > big deal, I think there are several ways to fix it. The odd thing is that the > build failed due to a rather unexpected change in C++ preprocessor (g++ -E or > cpp). > > Let's assume I have a test.cpp file containing this: > > #define MYMACRO(a, b) ""a", "b"" > MYMACRO(x,y) > > Now `cpp test.cpp' (or `g++ -E test.cpp') on rawhide produces: That is expected, and in F23 you get the same behavior if you use -std=c++11 or -std=c++14. In C++11 and later the language has user defined literals, so if you just want to concatenate strings, you need to put a whitespace in between them, otherwise the preprocessor considers ""a as user defined literal, similarly for ", "b and that is why it is not macro expanded. Just use #define MYMACRO(a, b) "" a ", " b "" Jakub -- devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxxx http://lists.fedoraproject.org/admin/lists/devel@xxxxxxxxxxxxxxxxxxxxxxx
