labath added a comment.

In https://reviews.llvm.org/D43688#1017652, @amccarth wrote:

> In https://reviews.llvm.org/D43688#1017638, @labath wrote:
>
> > On non-windows systems we're expected to pick up the name from the symbol 
> > table. Is there such a thing on windows as well?
>
>
> Given that constant is declared with visibility("hidden"), why would it end 
> up in a symbol table?  Windows DLLs have tables for items explicitly 
> exported, but that's contrary to asking the symbol to be hidden.


visibility((hidden)) means it won't end up in the *exported* symbol table 
(.dynsym on linux). However, the compiler will still put it into the local 
symbol table (.symtab, which is not used by the linker or at runtime, but the 
debugger can use it to get more insight). I have no idea how these things work 
on windows. If we have no way of finding this variable without debug info, then 
possibly the test just does not makes sense on windows.

>> I think this could also be related to your  breakpoint location resolving 
>> problem. The test explicitly calls `self.registerSharedLibrariesWithTarget` 
>> which explicitly adds the shared library to the list of target modules, so 
>> (assuming registerSharedLibrariesWithTarget works on windows) this test 
>> should not depend on automatic library searching in lldb. I'm guessing you 
>> have some problems looking things up when debug info is absent.
> 
> No, registering the libraries doesn't work on Windows (as discussed in the 
> other patch were we introduced the -2 magic value).  The Windows search rules 
> for DLLs are quite complex -- it would be very difficult to replicate them in 
> lldb.

Yes, but here I am not talking about parsing the imports table of the EXE and 
trying to replicate the OS search logic. Here, the test explicitly calls 
SBTarget.AddModule and specifies the full path of the module to add. I think 
this should work regardless of the platform.

>> With all that in mind, I don't think this patch would hurt this test, but I 
>> don't believe it will help you getting the test passing either, so I would 
>> keep the num_expected_locations as-is (the LLDB_TEST_API thingy is obviously 
>> fine).
> 
> But that would leave the test failing for a reason other than the underlying 
> problem:  that we can't resolve the symbol, which probably indicates an 
> incomplete implementation somewhere.  I think a test that failure that points 
> to the root problem is more useful than a general 
> this-doesn't-even-link-on-Windows error.

IIUC, the LLDB_TEST_API is the thing which fixes the link error. I have no 
objections to that.

The part that is not clear to me is why the test is failing to resolve the 
breakpoint even though the module was explicitly added through 
SBTarget.AddImage. Can you check at what the module list looks like after the 
AddImage call?


https://reviews.llvm.org/D43688



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