https://gcc.gnu.org/bugzilla/show_bug.cgi?id=70412
Bug ID: 70412
Summary: -Wswitch and functions that can only return a small
set of values
Product: gcc
Version: 5.3.0
Status: UNCONFIRMED
Severity: enhancement
Priority: P3
Component: c
Assignee: unassigned at gcc dot gnu.org
Reporter: izaberina at gmail dot com
Target Milestone: ---
$ cat wswitch.c
#include <stdio.h>
typedef enum { a, b, c, d, e } letter;
letter func (int arg) {
if (arg > 0) return a;
return b;
}
int main() {
switch(func(7)) {
case a: puts("a"); break;
case b: puts("b"); break;
}
return 0;
}
$ gcc -Wall wswitch.c
wswitch.c: In function 'main':
wswitch.c:11:3: warning: enumeration value 'c' not handled in switch [-Wswitch]
switch(func(7)) {
^
wswitch.c:11:3: warning: enumeration value 'd' not handled in switch [-Wswitch]
wswitch.c:11:3: warning: enumeration value 'e' not handled in switch [-Wswitch]
This is more of a question than a bug report: does that code need a default
case? I think it shouldn't, it handles all the possible return values...
Is that warning useful?
For the records, clang 3.7 reports a very similar warning.
