[LLD][COFF] Don't take into account the 'age' when looking for PDB type server

[aganea]

Summary

The age field is only there to say how many times an OBJ or a PDB was incrementally linked. It shouldn't be used to validate the link between the OBJ and the PDB.
I've ensured that linking a large project yields the same output as link.exe without /ignore:4099
This should fix the LNK4099 issues you're seeing on Chrome.

[thakis]

Test?

[aganea]

@thakis : Updated the existing test to fail without this patch.

[rnk]

lgtm

Wait, did someone enable phab memes in the last update? This is too silly. =p

[smeenai]

Phabricator memes are the best thing about Phabricator :)

shipit has been around since Jun 14 2016 according to https://reviews.llvm.org/macro/, so I'm not sure why it would suddenly start appearing. Macros are only active if the name appears by itself on a line though, so perhaps you just never happened to do that before?

[aganea]

Maybe Reid was talking about this icon, was it there before?

[rnk]

In D62837#1530228, @smeenai wrote:

Phabricator memes are the best thing about Phabricator :)

shipit has been around since Jun 14 2016 according to https://reviews.llvm.org/macro/, so I'm not sure why it would suddenly start appearing. Macros are only active if the name appears by itself on a line though, so perhaps you just never happened to do that before?

I though Phab had "serious mode" that we enabled to disable all the old "clowncopterize" flavor text. But, I guess that's all been gone since 2014:
https://secure.phabricator.com/D8812

lld/trunk/COFF/DebugTypes.cpp

TypeServerSource::findFromFile(const ObjFile *DependentFile) {
   if (!PDB.second)
     return createFileError(
         *P, createStringError(inconvertibleErrorCode(), PDB.first.c_str()));
 
   pdb::PDBFile &PDBFile = (PDB.second)->Session->getPDBFile();
   pdb::InfoStream &Info = cantFail(PDBFile.getPDBInfoStream());
 
   // Just because a file with a matching name was found doesn't mean it can be
-  // used. The GUID and Age must match between the PDB header and the OBJ
+  // used. The GUID must match between the PDB header and the OBJ
   // TypeServer2 record. The 'Age' is used by MSVC incremental compilation.
-  if (Info.getGuid() != TS.getGuid() || Info.getAge() != TS.getAge())
+  if (Info.getGuid() != TS.getGuid())
     return createFileError(
         TS.Name,
         make_error<pdb::PDBError>(pdb::pdb_error_code::signature_out_of_date));
 
   return PDB.second;
 }
 
 // FIXME: Temporary interface until PDBLinker::maybeMergeTypeServerPDB() is

lld/trunk/test/COFF/Inputs/pdb-type-server-valid-signature.yaml

Relocations:
         Type:            IMAGE_REL_AMD64_SECTION
   - Name:            '.debug$T'
     Characteristics: [ IMAGE_SCN_CNT_INITIALIZED_DATA, IMAGE_SCN_MEM_DISCARDABLE, IMAGE_SCN_MEM_READ ]
     Alignment:       1
     Types:
       - Kind:            LF_TYPESERVER2
         TypeServer2:
           Guid:            '{8DABD2A0-28FF-CB43-9BAF-175B77B76414}'
-          Age:             1
+          Age:             18
           Name:            'pdb-diff-cl.pdb'
   - Name:            '.text$mn'
     Characteristics: [ IMAGE_SCN_CNT_CODE, IMAGE_SCN_MEM_EXECUTE, IMAGE_SCN_MEM_READ ]
     Alignment:       16
     SectionData:     33C0C3
 symbols:
   - Name:            '.debug$S'
     Value:           0