In #99726, `-fptrauth-type-info-vtable-pointer-discrimination` was
introduced, which is intended to enable type and address discrimination
for type_info vtable pointers. However, some codegen logic for actually
enabling address discrimination was missing. This patch addresses the
issue.
Fixes#101716
Reland https://github.com/llvm/llvm-project/pull/75912
The differences of this PR between
https://github.com/llvm/llvm-project/pull/75912 are:
- Fixed a regression in `Decl::isInAnotherModuleUnit()` in DeclBase.cpp
pointed by @mizvekov and add the corresponding test.
- Fixed the regression in windows
https://github.com/llvm/llvm-project/issues/97447. The changes are in
`CodeGenModule::getVTableLinkage` from
`clang/lib/CodeGen/CGVTables.cpp`. According to the feedbacks from MSVC
devs, the linkage of vtables won't affected by modules. So I simply
skipped the case for MSVC.
Given this is more or less fundamental to the use of modules. I hope we
can backport this to 19.x.
This reverts commit 18f3bcbb13ca83d33223b00761d8cddf463e9ffb, 15bb02650e26875c48889053d6a9697444583721 and
99873b35da7ecb905143c8a6b8deca4d4416f1a9.
See the post commit message in
https://github.com/llvm/llvm-project/pull/75912 to see the reasons.
named modules
Close https://github.com/llvm/llvm-project/issues/97313
In the previous patch (https://github.com/llvm/llvm-project/pull/75912),
I made an oversight that I ignored the templates in named module when
calculating the linkage for the vtables. In this patch, I tried to
correct the behavior by merging the logics to calculate the linkage with
key functions with named modules.
