If the macro
NDEBUG
was defined at the moment
<assert.h>
was last included, the macro
assert()
generates no code, and hence does nothing at all.
Otherwise, the macro
assert()
prints an error message to standard error and terminates the program
by calling
abort(3)
if
expression
is false (i.e., compares equal to zero).
The purpose of this macro is to help the programmer find bugs in
his program.
The message "assertion failed in file foo.c, function
do_bar(), line 1287" is of no help at all to a user.
RETURN VALUE
No value is returned.
CONFORMING TO
POSIX.1-2001, C89, C99.
In C89,
expression
is required to be of type
int
and undefined behavior results if it is not, but in C99
it may have any scalar type.
BUGS
assert()
is implemented as a macro; if the expression tested has side-effects,
program behavior will be different depending on whether
NDEBUG
is defined.
This may create Heisenbugs which go away when debugging
is turned on.
This page is part of release 3.14 of the Linux
man-pages
project.
A description of the project,
and information about reporting bugs,
can be found at
http://www.kernel.org/doc/man-pages/.