Coverity FORWARD_NULL - CID 10691

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CID: 10691
Checker: FORWARD_NULL
Category: No category available
CWE definition: http://cwe.mitre.org/data/definitions/476.html
File: /tmp/buildd/notify-osd-0.9.33/src/stack.c
Function: stack_get_slot_position()
Code snippet:
885 gint* x,
886 gint* y)
887 {
888 // sanity checks
At conditional: "!x" taking True branch
At conditional: "!y" taking False branch
CID 10691 - FORWARD_NULL
Comparing "x" to null implies that "x" might be null.
889 if (!x && !y)
890 return;
891
At conditional: "!self" taking True branch
892 if (!self || !IS_STACK (self))
893 {
CID 10691 - FORWARD_NULL
Dereferencing null variable "x".
894 *x = -1;

[Product Strategy Coverity Bug Uploader (coverity-uploader)]

Source file with Coverity annotations.

[Charles Kerr (charlesk)]

Coverity is right about the potential NULL dereference -- it looks like maybe (!x && !y) could be replaced with (!x || !y).

Even though the bug exists, it doesn't look like any of stack_get_slot_position()'s callers ever trigger it.

Apologies in advance if I'm stepping into someone else's code here... I've just been looking through the Coverity tickets to see what kind of issues or nonissues it's reporting :)