Reland https://reviews.llvm.org/D76696
All known crashes have been fixed, another attemption.
We have rolled out this to all internal users for a while, didn't see
big issues, we consider it is stable enough.
Reviewed By: sammccall
Subscribers: rsmith, hubert.reinterpretcast, ebevhan, jkorous, arphaman, kadircet, usaxena95, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D78350
Summary:
This patch would cause clang emit more diagnostics, but it is much better than https://reviews.llvm.org/D76831
```cpp
struct A {
A(int);
~A() = delete;
};
void k() {
A a;
}
```
before the patch:
/tmp/t3.cpp:24:5: error: no matching constructor for initialization of 'A'
A a;
^
/tmp/t3.cpp:20:3: note: candidate constructor not viable: requires 1 argument, but 0 were provided
A(int);
^
/tmp/t3.cpp:19:8: note: candidate constructor (the implicit copy constructor) not viable: requires 1 argument, but 0 were provided
struct A {
After the patch:
/tmp/t3.cpp:24:5: error: no matching constructor for initialization of 'A'
A a;
^
/tmp/t3.cpp:20:3: note: candidate constructor not viable: requires 1 argument, but 0 were provided
A(int);
^
/tmp/t3.cpp:19:8: note: candidate constructor (the implicit copy constructor) not viable: requires 1 argument, but 0 were provided
struct A {
^
/tmp/t3.cpp:24:5: error: attempt to use a deleted function
A a;
^
/tmp/t3.cpp:21:3: note: '~A' has been explicitly marked deleted here
~A() = delete;
Reviewers: sammccall
Reviewed By: sammccall
Subscribers: cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D77395
render the function deleted instead of rendering the program ill-formed.
This change also adds an enabled-by-default warning for the case where
an explicitly-defaulted special member function of a non-template class
is implicitly deleted by the type checking rules. (This fires either due
to this language change or due to pre-C++20 reasons for the member being
implicitly deleted). I've tested this on a large codebase and found only
bugs (where the program means something that's clearly different from
what the programmer intended), so this is enabled by default, but we
should revisit this if there are problems with this being enabled by
default.
llvm-svn: 343285
A defaulted default constructor for a class X is defined as deleted if [...]
- X is a union and all of its variant members are of const-qualified type.
A pedantic reading therefore says that
union X { };
has a deleted default constructor, which is both silly and almost
certainly unintended. Pretend as if this this read
- X is a union with one or more variant members, and all of its
variant members are of const-qualified type.
llvm-svn: 151394
decent diagnostics. Finish the work of combining all the 'ShouldDelete'
functions into one. In unifying the code, fix a minor bug where an anonymous
union with a deleted default constructor as a member of a union wasn't being
considered as making the outer union's default constructor deleted.
llvm-svn: 150862
function, provide a specialized diagnostic that indicates the kind of
special member function (default constructor, copy assignment
operator, etc.) and that it was implicitly deleted. Add a hook where
we can provide more detailed information later.
llvm-svn: 150611
I have on that's #if 0'ed out, and I don't know why it's failing to
delete the constructor. I'd appreciate if someone familiar with access
control could look into ShouldDeleteDefaultConstructor - thanks.
llvm-svn: 131486
Haojian Wu