Fix#67495, #72198
We build ill-formed AST nodes for invalid structured binding. For case
`int [_, b] = {0, 0};`, the `DecompositionDecl` is valid, and its
children `BindingDecl`s are valid but with a NULL type, this breaks
clang invariants in many places, and using these `BindingDecl`s can lead
to crashes. This patch fixes them by marking the DecompositionDecl and
its children invalid.
This would allow more AST nodes being preserved for broken code, and
have a more consistent valid bit for ref-type var decl (currently, a
ref-type var decl with a broken initializer is valid).
Per https://reviews.llvm.org/D76831#1973053, the initializer of a variable
should play no part in its "invalid" bit.
Reviewed By: sammccall
Differential Revision: https://reviews.llvm.org/D122935
Summary:
This patch contains 2 separate changes:
1) the initializer of a variable should play no part in decl "invalid" bit;
2) preserve the invalid initializer via recovery exprs;
With 1), we will regress the diagnostics (one big regression is that we loose
the "selected 'begin' function with iterator type" diagnostic in for-range stmt;
but with 2) together, we don't have regressions (the new diagnostics seems to be
improved).
Reviewers: sammccall
Reviewed By: sammccall
Subscribers: cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D78116
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
