Annex D (normative) Compatibility features [depr]

D.4 C++standard library headers [depr.cpp.headers]

For compatibility with prior C++International Standards, the C++standard library provides headers <ccomplex> ([depr.ccomplex.syn]), <cstdalign> ([depr.cstdalign.syn]), <cstdbool> ([depr.cstdbool.syn]), and <ctgmath> ([depr.ctgmath.syn]).
The use of these headers is deprecated.

D.4.1 Header <ccomplex> synopsis [depr.ccomplex.syn]

#include <complex>
The header <ccomplex> behaves as if it simply includes the header <complex> ([complex.syn]).

D.4.2 Header <cstdalign> synopsis [depr.cstdalign.syn]

#define __alignas_­is_­defined 1
The contents of the header <cstdalign> are the same as the C standard library header <stdalign.h>, with the following changes: The header <cstdalign> and the header <stdalign.h> shall not define a macro named alignas.
See also: ISO C 7.
15

D.4.3 Header <cstdbool> synopsis [depr.cstdbool.syn]

#define __bool_­true_­false_­are_­defined 1
The contents of the header <cstdbool> are the same as the C standard library header <stdbool.h>, with the following changes: The header <cstdbool> and the header <stdbool.h> shall not define macros named bool, true, or false.
See also: ISO C 7.
18

D.4.4 Header <ctgmath> synopsis [depr.ctgmath.syn]

#include <complex>
#include <cmath>
The header <ctgmath> simply includes the headers <complex> ([complex.syn]) and <cmath> ([cmath.syn]).
[Note
:
The overloads provided in C by type-generic macros are already provided in <complex> and <cmath> by “sufficient” additional overloads.
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