assert.h File Reference

POSIX.1-2008 compliant version of the assert macro. More...

Detailed Description

POSIX.1-2008 compliant version of the assert macro.

Author
Oliver Hahm olive.nosp@m.r.ha.nosp@m.hm@in.nosp@m.ria..nosp@m.fr
René Kijewski rene..nosp@m.kije.nosp@m.wski@.nosp@m.fu-b.nosp@m.erlin.nosp@m..de
Martine Lenders m.len.nosp@m.ders.nosp@m.@fu-b.nosp@m.erli.nosp@m.n.de

Definition in file assert.h.

#include "panic.h"
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Go to the source code of this file.

#define DEBUG_ASSERT_VERBOSE
 Activate verbose output for assert() when defined. More...
 
#define assert(cond)
 abort the program if assertion is false More...
 
#define static_assert(cond, ...)   { enum { static_assert_failed_on_div_by_0 = 1 / (!!(cond)) }; }
 static_assert for c-version < c11 More...
 
const char assert_crash_message []
 the string that is passed to panic in case of a failing assertion
 
NORETURN void _assert_failure (const char *file, unsigned line)
 Function to handle failed assertion. More...
 

Macro Definition Documentation

◆ assert

#define assert (   cond)
Value:
((cond) ? (void)0 : _assert_failure(RIOT_FILE_RELATIVE, \
__LINE__))

abort the program if assertion is false

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 application by calling core_panic().

The purpose of this macro is to help programmers find bugs in their programs.

With DEBUG_ASSERT_VERBOSE defined this will print also the file, the line and the function this assertion failed in.

If NDEBUG and DEBUG_ASSERT_VERBOSE are not defined, a failed assertion generates output similar to:

0x89abcdef
*** RIOT kernel panic:
FAILED ASSERTION.

...

Where 0x89abcdef is an address. This address can be used with tools like addr2line (or e.g. arm-none-eabi-addr2line for ARM-based code), objdump, or gdb (with the command info line *(0x89abcdef)) to identify the line the assertion failed in.

See also
http://pubs.opengroup.org/onlinepubs/9699919799/functions/assert.html

Definition at line 104 of file assert.h.

◆ DEBUG_ASSERT_VERBOSE

#define DEBUG_ASSERT_VERBOSE

Activate verbose output for assert() when defined.

Without this macro defined the assert() macro will just print the address of the code line the assertion failed in. With the macro defined the macro will also print the file, the code line and the function this macro failed in.

To define just add it to your CFLAGS in your application's Makefile:

CFLAGS += -DDEBUG_ASSERT_VERBOSE

Definition at line 46 of file assert.h.

◆ static_assert

#define static_assert (   cond,
  ... 
)    { enum { static_assert_failed_on_div_by_0 = 1 / (!!(cond)) }; }

static_assert for c-version < c11

Generates a division by zero compile error when cond is false

Definition at line 123 of file assert.h.

Function Documentation

◆ _assert_failure()

NORETURN void _assert_failure ( const char *  file,
unsigned  line 
)

Function to handle failed assertion.

Note
This function was introduced for memory size optimization
Warning
this function NEVER returns!
Parameters
[in]fileThe file name of the file the assertion failed in
[in]lineThe code line of file the assertion failed in
_assert_failure
NORETURN void _assert_failure(const char *file, unsigned line)
Function to handle failed assertion.