[[clang::lifetimebound]] is ignored in some cases when declaration and definition do not apply the attribute consistently

[ddkilzer]

[[clang::lifetimebound]] is ignored in some cases when declaration and definition do not apply the attribute consistently.

The [[clang::lifetimebound]] attribute on a method's implicit object parameter (the this pointer) is not properly detected when:

1. A non-template or specialized-template method declaration had the attribute but the out-of-line definition did not
2. A template method out-of-line definition had the attribute but the declaration did not

The Godbolt test should show 9 -Wdangling warnings, but currently only shows 6 warnings: https://godbolt.org/z/ra5avj8e4

rdar://167796787

[ddkilzer]

Cc @Xazax-hun @emaxx-google FYI

[llvmbot]

@llvm/issue-subscribers-clang-temporal-safety

Author: David Kilzer (ddkilzer)

Details

`[[clang::lifetimebound]]` is ignored in some cases when declaration and definition do not apply the attribute consistently.

The [[clang::lifetimebound]] attribute on a method's implicit object parameter (the this pointer) is not properly detected when:

1. A non-template or specialized-template method declaration had the attribute but the out-of-line definition did not
2. A template method out-of-line definition had the attribute but the declaration did not

The Godbolt test should show 9 -Wdangling warnings, but currently only shows 6 warnings: https://godbolt.org/z/ra5avj8e4

rdar://167796787

[Xazax-hun]

I think this might be fixed by #172146

cc @usx95