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by CJefferson 5274 days ago
Why do you think the compiler with optimizations will remove the assertion?

The compiler will realise that:

    assert(assert(line != NULL && longest != NULL && "memory error");
Is equivalent to:

    assert(line != NULL && longest != NULL);
But there doesn't seem anything wrong with that.
3 comments
tptacek 5274 days ago
Production code is supposed to define away the assertions. It is an actual error to manage important program state with asserts.

(That doesn't make these particular asserts an error).

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zedshaw 5273 days ago
In the earlier chapters they setup a Makefile with full debugging on so these don't get removed. It's mostly just for this one exercise, and in the rest of the book they use a set of debug macros I wrote:

http://c.learncodethehardway.org/book/learn-c-the-hard-waych...

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scott_s 5274 days ago
In support of tptacek's comment, an abbreviate version of what's in assert.h on my OSX system:

  #ifdef NDEBUG
  #define assert(e)   ((void)0)
  #else

  #define assert(e)  \
    ((void) ((e) ? 0 : __assert (#e, __FILE__, __LINE__)))
  #define __assert(e, file, line) \
    ((void)printf ("%s:%u: failed assertion `%s'\n", file, line, e), abort())
So, if NDEBUG ("no debug") is defined, which it is if optimizations are turned on, asserts become a no-op.
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