[PATCH] D11334: [Sema] Call to deleted functions are supposed to be verboten

[Davide Italiano]

On Tue, Jul 21, 2015 at 3:26 PM, Davide Italiano <dccitaliano at gmail.com> wrote:
> On Tue, Jul 21, 2015 at 2:59 PM, Richard Smith <richard at metafoo.co.uk> wrote:
>> rsmith added inline comments.
>>
>> ================
>> Comment at: lib/Sema/SemaOverload.cpp:11608
>> @@ +11607,3 @@
>> +
>> +    // Calls to deleted member functions are verboten.
>> +    if (Method && Method->isDeleted())
>> ----------------
>> This check should happen when we build the `MemberExpr`, not when we use it. It looks like the bug is in `Sema::BuildMemberReferenceExpr`, at around line 1050 of SemaExprMember.cpp:
>>
>>   bool ShouldCheckUse = true;
>>   if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(MemberDecl)) {
>>     // Don't diagnose the use of a virtual member function unless it's
>>     // explicitly qualified.
>>     if (MD->isVirtual() && !SS.isSet())
>>       ShouldCheckUse = false;
>>   }
>>
>>   // Check the use of this member.
>>   if (ShouldCheckUse && DiagnoseUseOfDecl(MemberDecl, MemberLoc))
>>     return ExprError();
>>
>> This is wrong: we should `DiagnoseUseOfDecl` (including diagnosing the use of a deleted function) even for a virtual function. Which tests fail if we unconditionally `DiagnoseUseOfDecl` here?
>>
>
> Luckily only one.
>
> FAIL: Clang :: SemaCXX/attr-deprecated.cpp (5733 of 8388)
> ******************** TEST 'Clang :: SemaCXX/attr-deprecated.cpp'
> FAILED ********************
> Script:
> --
> /exps/llvm2/build/./bin/clang -cc1 -internal-isystem
> /exps/llvm2/build/bin/../lib/clang/3.8.0/include -nostdsysteminc
> /exps/llvm2/tools/clang/test/SemaCXX/attr-deprecated.cpp -verify
> -fexceptions
> --
> Exit Code: 1
>
> Command Output (stderr):
> --
> error: 'warning' diagnostics seen but not expected:
>   File /exps/llvm2/tools/clang/test/SemaCXX/attr-deprecated.cpp Line
> 34: 'f' is deprecated
>   File /exps/llvm2/tools/clang/test/SemaCXX/attr-deprecated.cpp Line
> 50: 'f' is deprecated
>   File /exps/llvm2/tools/clang/test/SemaCXX/attr-deprecated.cpp Line
> 65: 'f' is deprecated
> error: 'note' diagnostics seen but not expected:
>   File /exps/llvm2/tools/clang/test/SemaCXX/attr-deprecated.cpp Line
> 29: 'f' has been explicitly marked deprecated here
>   File /exps/llvm2/tools/clang/test/SemaCXX/attr-deprecated.cpp Line
> 29: 'f' has been explicitly marked deprecated here
>   File /exps/llvm2/tools/clang/test/SemaCXX/attr-deprecated.cpp Line
> 62: 'f' has been explicitly marked deprecated here
> 6 errors generated.
>
> --

Looking at the tests it seems we emit the warnings we previously
emitted only for fully qualified functions also for non-fully
qualified functions.
If you think we should diagnose in both cases, I'll modify the test to
take them in account.

--
Davide