[thirdparty/gcc.git] / gcc / doc / gcc / c-implementation-defined-behavior / library-functions.rst

..
  Copyright 1988-2022 Free Software Foundation, Inc.
  This is part of the GCC manual.
  For copying conditions, see the copyright.rst file.

.. _library-functions-implementation:

Library Functions
*****************

The behavior of most of these points are dependent on the implementation
of the C library, and are not defined by GCC itself.

* The null pointer constant to which the macro ``NULL`` expands
  (C90 7.1.6, C99 7.17, C11 7.19).

  In ``<stddef.h>``, ``NULL`` expands to ``((void *)0)``.  GCC
  does not provide the other headers which define ``NULL`` and some
  library implementations may use other definitions in those headers.
Commit	Line	Data
c63539ff ML	1	..
	2	Copyright 1988-2022 Free Software Foundation, Inc.
	3	This is part of the GCC manual.
	4	For copying conditions, see the copyright.rst file.
	5
	6	.. _library-functions-implementation:
	7
	8	Library Functions
	9	*****************
	10
	11	The behavior of most of these points are dependent on the implementation
	12	of the C library, and are not defined by GCC itself.
	13
	14	* The null pointer constant to which the macro ``NULL`` expands
	15	(C90 7.1.6, C99 7.17, C11 7.19).
	16
	17	In ``<stddef.h>``, ``NULL`` expands to ``((void *)0)``. GCC
	18	does not provide the other headers which define ``NULL`` and some
3ed1b4ce	19	library implementations may use other definitions in those headers.