V661. Suspicious expression 'A[B < C]'. Probably meant 'A[B] < C'.

The analyzer has detected a suspicious code fragment where an array item is being accessed. A logical expression is used as an array index.

Here are examples of such expressions: Array[A >= B], Array[A != B]. Perhaps the closing square bracket is in the wrong place. These errors usually occur through misprints.

Consider an example of incorrect code:

if ((bs->inventory[INVENTORY_ROCKETLAUNCHER] <= 0 || 
     bs->inventory[INVENTORY_ROCKETS < 10]) && <<== ERROR!
    (bs->inventory[INVENTORY_RAILGUN] <= 0 || 
     bs->inventory[INVENTORY_SLUGS] < 10)) {
        return qfalse;
}

This code is compilable but works incorrectly. It's highly probable that the following text should be written instead:

if ((bs->inventory[INVENTORY_ROCKETLAUNCHER] <= 0 || 
     bs->inventory[INVENTORY_ROCKETS] < 10) &&
    (bs->inventory[INVENTORY_RAILGUN] <= 0 || 
     bs->inventory[INVENTORY_SLUGS] < 10)) {
        return qfalse;
}

Note. The analyzer doesn't generate the warning all the time a logical expression is placed inside square brackets. It is sometimes justified. For instance, such an exception is the case when an array consists of only two items:

int A[2];
A[x != y] = 1;