What's new in the C++11 preprocessor?

Question

This image from Microsoft implies that, on the roadmap to support for C++14, there is work to be done in Visual Studio to support the C++11 preprocessor:

What changes does this involve?

Answer 1

What's new in the C++11 preprocessor?

C++03 used the C90 preprocessor, and C++11 added features from the C99 preprocessor on top of that. Those added features are:

• arithmetic with extended integer types;
• mixed string literal concatenation;
• _Pragma operator;
• variadic macros and empty macro arguments.

What changes does this involve?

Even in Visual Studio per this chart, not many, since Microsoft don't actually have to implement the C11 changes to gain C++11 compliance. In implying this, the chart could be deemed misleading; evidently they are targetting some C11 support for C++14 but, then again, I can't see that C11 changes much anyway.

However, to achieve compliance with C++11, according to the chart Microsoft do need to bring themselves up to proper C99 standards.