[shakna]

It's handy in C for guarding parts of the language, as you often have to check return values anyway.

    if(malloc(10000 * sizeof foo) == NULL) {
      // Error processing
    } // No need for an else branch here.

[the-dude]

Missing assingment.

[shakna]

    int success = NULL;

    if(success = malloc(...)) {
    }
    if(success = malloc(...)) {
    }
    if(success = malloc(...)) {
    }

[slavik81]

That will result in undefined behaviour if the value returned by malloc is greater than INT_MAX. If you really need an integer, use intptr_t. But, generally it makes more sense to just use a pointer.

    char* p = NULL;
    if (p = malloc(...)) {
      ...
    }