xref: /llvm-project/clang-tools-extra/docs/clang-tidy/checks/bugprone/infinite-loop.rst (revision 6e566bc5523f743bc34a7e26f050f1f2b4d699a8)
1.. title:: clang-tidy - bugprone-infinite-loop
2
3bugprone-infinite-loop
4======================
5
6Finds obvious infinite loops (loops where the condition variable is not changed
7at all).
8
9Finding infinite loops is well-known to be impossible (halting problem).
10However, it is possible to detect some obvious infinite loops, for example, if
11the loop condition is not changed. This check detects such loops. A loop is
12considered infinite if it does not have any loop exit statement (``break``,
13``continue``, ``goto``, ``return``, ``throw`` or a call to a function called as
14``[[noreturn]]``) and all of the following conditions hold for every variable in
15the condition:
16
17- It is a local variable.
18- It has no reference or pointer aliases.
19- It is not a structure or class member.
20
21Furthermore, the condition must not contain a function call to consider the loop
22infinite since functions may return different values for different calls.
23
24For example, the following loop is considered infinite `i` is not changed in
25the body:
26
27.. code-block:: c++
28
29  int i = 0, j = 0;
30  while (i < 10) {
31    ++j;
32  }
33