C Language and Libraries Help (clang.hlp) (Table of Contents; Topic list)
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assert
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─────Run-Time Library───────────────────────────────────────────────────────
 
     The assert routine prints a diagnostic message and calls the abort
     routine if <expression> is false (0). The diagnostic message has
     the form
 
          Assertion failed: expression, file filename, line linenumber
 
     where <filename> is the name of the source file and <linenumber>
     is the line number of the assertion that failed in the source
     file. No action is taken if <expression> is true (nonzero).
 
     In Windows, the diagnostic message appears in an "Assertion
     Failed" pop-up window.
 
     The assert routine (implemented as a macro) is typically used to
     identify program logic errors. The given expression should be
     chosen so that it holds true only if the program is operating as
     intended.
 
     After a program has been debugged, the special "no debug"
     identifier NDEBUG can be used to remove assert calls from the
     program.
 
     If NDEBUG is defined (by any value) with a /D command-line option
     or with a #define directive, the C preprocessor removes all assert
     calls from the program source. However, at warning level 4, you
     will get the following warnings: 'Statement has no effect' and
     'Unreferenced formal parameters.'
     See: Define Constants and Macros (in CL Help)
          Set Warning Levels (in CL Help)
 
     Return Value
 
     None.
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