Annex C (informative) Compatibility [diff]

C.6 C standard library [diff.library]

C.6.3 Modifications to definitions [diff.mods.to.definitions]

C.6.3.3 Header <assert.h> [diff.header.assert.h]

The token static_­assert is a keyword in C++.
It does not appear as a macro name defined in <cassert>.