https://gcc.gnu.org/bugzilla/show_bug.cgi?id=7654
Eric Gallager <egallager at gcc dot gnu.org> changed:
What |Removed |Added
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CC| |egallager at gcc dot gnu.org
--- Comment #12 from Eric Gallager <egallager at gcc dot gnu.org> ---
(In reply to Martin Sebor from comment #11)
> I'll confirm this ancient request.
>
> Bug 78736 asks for something similar, and I'm working on enhancing the
> solution there even further (to diagnose assigning constants that don't have
> a corresponding enumerator in the destination type). I'll add that on the
> following slightly modified test case Clang issues the warnings below:
>
> $ cat t.C && clang -S -Wall -Wextra -Weverything -xc t.C
> void f (int i)
> {
> enum e1 { e1a, e1b };
> enum e1 e1v;
> enum e2 { e2a, e2b };
> enum e2 e2v;
>
> e1v = 1; // no warning
> e1v = 3; // warning
> e1v = e1a; // ok
> e2v = e1v; // warning
> i = e1v; // ok I guess
> e2v = i; // warning
> }
> t.C:9:9: warning: integer constant not in range of enumerated type 'enum e1'
> [-Wassign-enum]
> e1v = 3; // warning
> ^
> t.C:11:9: warning: implicit conversion from enumeration type 'enum e1' to
> different enumeration type 'enum e2' [-Wenum-conversion]
> e2v = e1v; // warning
> ~ ^~~
> t.C:13:9: warning: implicit conversion changes signedness: 'int' to 'enum e2'
> [-Wsign-conversion]
> e2v = i; // warning
> ~ ^
> t.C:1:6: warning: no previous prototype for function 'f'
> [-Wmissing-prototypes]
> void f (int i)
> ^
> 4 warnings
gcc now prints:
$ /usr/local/bin/gcc -c -S -Wall -Wextra -Wconversion -Wsign-conversion
-Wmissing-prototypes -pedantic -xc 7654.c
7654.c:1:6: warning: no previous prototype for 'f' [-Wmissing-prototypes]
1 | void f (int i)
| ^
7654.c: In function 'f':
7654.c:11:6: warning: implicit conversion from 'enum e1' to 'enum e2'
[-Wenum-conversion]
11 | e2v = e1v; // warning
| ^
7654.c:6:10: warning: variable 'e2v' set but not used
[-Wunused-but-set-variable]
6 | enum e2 e2v;
| ^~~
$
so, gcc has -Wenum-conversion now, but it is still missing warnings from
-Wassign-enum and -Wsign-conversion on this testcase.
