C++ without real static_assert() can be incompatible with the C fallback
as presented in openjdk.
A pre-C11 compiler can be picky on the implementation.
The existing definition caused issues as GCC only provides _Static_assert
when building C11 code.
This follows the C standard: static_assert available since C11.
Fixes https://rt.perl.org/Public/Bug/Display.html?id=134023
This declaration conforms to the C11 standard
Reference: ISO/IEC 9899:201x 7.2 Diagnostics <assert.h>
_Static_assert performs compile-time assertion checking.
According to ISO/IEC 9899:201x (draft) 7.2 Diagnostics <assert.h> defines
the static_assert macro which expands to _Static_assert. It's not
conditionalized by NDEBUG like the assert macro.
According to ISO/IEC N3242=11-0012 (C++1x) the <cassert> header shall
define only the assert macro, but not static_assert as it's already part
of the C++11 language.
Allow to define static_assert in C++ prior the C++11 standard. It might be
broken but a nonstandard C++ compiler might support C11-like _Static_assert
feature. Note that it's fatal for g++ 5.4, but it works for clang++ 3.8.1.
Approved by <joerg>.
only be exposed if _NETBSD_SOURCE is defined. To make life less complicated,
define _assert() in terms of assert(), since they always seem to have identical
definitions.
_assert() was removed back in 1993, but got reinstated with the 4.4Lite
import. Maybe it should go again. Nothing in the tree uses it.
the __assert() helper function is declared once if <assert.h> is included
multiple times.
Don't support the _assert() macro, nothing uses it and it pollutes the
user's namespace.
kamil