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Warnings most often mean "here is a bug which will likely cause your program to crash or misbehave". They do not mean "here's something that you can optionally fix when you can spare the time". See...
Answer
#2: Post edited
by
Lundin
·
2021-08-31T10:12:41Z (about 3 years ago)
- Warnings most often mean "here is a bug which will likely cause your program to crash or misbehave". They do _not_ mean "here's something that you can optionally fix when you can spare the time". See [What must a C compiler do when it finds an error?](https://software.codidact.com/posts/277340)
In your specific case, ignoring the warning leads to undefined behavior, meaning anything can happen. For example runaway code, crashes caused by stack corruption/wrong calling convention, wrong results calculated on garbage values, code getting incorrectly optimized and parts of it removed etc etc. [What is undefined behavior and how does it work?](https://software.codidact.com/posts/277486)
- Warnings most often mean "here is a bug which will likely cause your program to crash or misbehave". They do _not_ mean "here's something that you can optionally fix when you can spare the time". See [What must a C compiler do when it finds an error?](https://software.codidact.com/posts/277340)
- In your specific case, ignoring the warning leads to undefined behavior, meaning anything can happen. This is mentioned in the C standard C17 6.9.1/12:
- > If the } that terminates a function is reached, and the value of the function call is used by the caller, the behavior is undefined.
- For example runaway code, crashes caused by stack corruption/wrong calling convention, wrong results calculated on garbage values, code getting incorrectly optimized and parts of it removed etc etc. [What is undefined behavior and how does it work?](https://software.codidact.com/posts/277486)
#1: Initial revision
by
Lundin
·
2021-08-31T10:09:55Z (about 3 years ago)
Warnings most often mean "here is a bug which will likely cause your program to crash or misbehave". They do _not_ mean "here's something that you can optionally fix when you can spare the time". See [What must a C compiler do when it finds an error?](https://software.codidact.com/posts/277340) In your specific case, ignoring the warning leads to undefined behavior, meaning anything can happen. For example runaway code, crashes caused by stack corruption/wrong calling convention, wrong results calculated on garbage values, code getting incorrectly optimized and parts of it removed etc etc. [What is undefined behavior and how does it work?](https://software.codidact.com/posts/277486)