Sema: Methods in unavailable classes are unavailable
Similar to the template cases in r262050, when a C++ method in an
unavailable struct/class calls unavailable API, don't diagnose an error.
I.e., this case was failing:
void foo() __attribute__((unavailable));
struct __attribute__((unavailable)) A {
void bar() { foo(); }
};
Since A is unavailable, A::bar is allowed to call foo. However, we were
emitting a diagnostic here. This commit checks up the context chain
from A::bar, in a manner inspired by SemaDeclAttr.cpp:isDeclUnavailable.
I expected to find other related issues but failed to trigger them:
- I wondered if DeclBase::getAvailability should check for
`TemplateDecl` instead of `FunctionTemplateDecl`, but I couldn't find
a way to trigger this. I left behind a few extra tests to make sure
we don't regress.
- I wondered if Sema::isFunctionConsideredUnavailable should be
symmetric, checking up the context chain of the callee (this commit
only checks up the context chain of the caller). However, I couldn't
think of a testcase that didn't require first referencing the
unavailable type; this, we already diagnose.
rdar://problem/
25030656
llvm-svn: 262921