Prefer the new flag -lld-allow-duplicate-weak (which was added recently
in a67ae8c0fd301a11e2a058e8035304cfc70a3e91), over the old -lldmingw.
The -lldmingw option enables a number of different behaviours, while
this test only is interested in one aspect of them.
This should allow making -lldmingw more strict with not enabling MSVC
specific behaviours like inferring lib directories automatically from
the environment, as being pursued in https://reviews.llvm.org/D144084.
This test uses lots of lld-link specific linker options that don't
work as such in mingw command lines.
Differential Revision: https://reviews.llvm.org/D148168
The linkage/visibility of `__profn_*` variables are derived
from the profiled functions.
extern_weak => linkonce
available_externally => linkonce_odr
internal => private
extern => private
_ => unchanged
The linkage/visibility of `__profc_*`/`__profd_*` variables are derived from
`__profn_*` with linkage/visibility wrestling for Windows.
The changes can be folded to the following without changing semantics.
```
if (TT.isOSBinFormatCOFF() && !NeedComdat) {
Linkage = GlobalValue::InternalLinkage;
Visibility = GlobalValue::DefaultVisibility;
}
```
That said, I think we can just delete the code block.
An extern/internal function will now use private `__profc_*`/`__profd_*`
variables, instead of internal ones. This saves some symbol table entries.
A non-comdat {linkonce,weak}_odr function will now use hidden external
`__profc_*`/`__profd_*` variables instead of internal ones. There is potential
object file size increase because such symbols need `/INCLUDE:` directives.
However such non-comdat functions are rare (note that non-comdat weak
definitions don't prevent duplicate definition error).
The behavior changes match ELF.
Reviewed By: rnk
Differential Revision: https://reviews.llvm.org/D103355
