src/include/stdnoreturn.h, branch releng/11.2

Revert r330897:

2018-03-29T02:50:57Z

This was intended to be a non-functional change. It wasn't. The commit message was thus wrong. In addition it broke arm, and merged crypto related code. Revert with prejudice. This revert skips files touched in r316370 since that commit was since MFCed. This revert also skips files that require $FreeBSD$ property changes. Thank you to those who helped me get out of this mess including but not limited to gonzo, kevans, rgrimes. Requested by: gjb (re)

Partial merge of the SPDX changes

2018-03-14T03:19:51Z

These changes are incomplete but are making it difficult to determine what other changes can/should be merged. No objections from: pfg

Simply disallow to be used in combination with C++.

2012-01-03T23:05:23Z

There is no way one could possibly use this header file in combination with C++ code. The problem is that in C11 the `noreturn' macro expands to the `_Noreturn' function specifier, while in C++11 the `noreturn' keyword is an attribute. So in C11 you have to write: noreturn void exit(int status); While in C++11 you have to write: [[noreturn]] void exit(int status); It is impossible to #define noreturn for C++ in such a way that it allows both conventions. By intentionally breaking this header this way, we prevent people from using this header in their C++<11 sources.

Add and .

2011-12-25T20:51:40Z

Even though these header files make little sense to me, they are part of the standard. By including these header files, you can simply use `alignas', `alignof' and `noreturn' instead of the underscore-prefixed versions.