modernize-deprecated-headers

Some headers from C library were deprecated in C++ and are no longer welcome in C++ codebases. Some have no effect in C++. For more details refer to the C++ 14 Standard [depr.c.headers] section.

This check replaces C standard library headers with their C++ alternatives and removes redundant ones.

Important note: the Standard doesn’t guarantee that the C++ headers declare all the same functions in the global namespace. The check in its current form can break the code that uses library symbols from the global namespace.

• <assert.h>

• <complex.h>

• <ctype.h>

• <errno.h>

• <fenv.h> // deprecated since C++11

• <float.h>

• <inttypes.h>

• <limits.h>

• <locale.h>

• <math.h>

• <setjmp.h>

• <signal.h>

• <stdarg.h>

• <stddef.h>

• <stdint.h>

• <stdio.h>

• <stdlib.h>

• <string.h>

• <tgmath.h> // deprecated since C++11

• <time.h>

• <uchar.h> // deprecated since C++11

• <wchar.h>

• <wctype.h>

If the specified standard is older than C++11 the check will only replace headers deprecated before C++11, otherwise – every header that appeared in the previous list.

These headers don’t have effect in C++:

• <iso646.h>

• <stdalign.h>

• <stdbool.h>