[LLD] [COFF] Align Extended DLL Characteristics

[penzn]

Summary

Match Extended DLL Characteristics alignment produced MSVC linker. Remove debug directory alignment introduced in D70606. This is required for CETCOMPAT setting to work in presence of other debug directories (CodeView, for example), otherwise it would not be recognizer by the Windows loader.

D89921 is a broader variant of this change.

[vitalybuka]

Both looks LGTM, but someone from LLD need needs to look at it.

[thakis]

(Sounds like the plan is to move forward with the other patch.)

[penzn]

Abandoned in favor of D89921

lld/COFF/Writer.cpp

if (!symtab->localImportChunks.empty()) {
     for (Chunk *c : symtab->localImportChunks)
       rdataSec->addChunk(c);
   }
 
   // Create Debug Information Chunks
   OutputSection *debugInfoSec = config->mingw ? buildidSec : rdataSec;
   if (config->debug || config->repro || config->cetCompat) {
     debugDirectory = make<DebugDirectoryChunk>(debugRecords, config->repro);
-    debugDirectory->setAlignment(4);
     debugInfoSec->addChunk(debugDirectory);
   }
 
   if (config->debug) {
     // Make a CVDebugRecordChunk even when /DEBUG:CV is not specified.  We
     // output a PDB no matter what, and this chunk provides the only means of
     // allowing a debugger to match a PDB and an executable.  So we need it even
     // if we're ultimately not going to write CodeView data to the PDB.
     buildId = make<CVDebugRecordChunk>();
     debugRecords.push_back({COFF::IMAGE_DEBUG_TYPE_CODEVIEW, buildId});
   }
 
   if (config->cetCompat) {
     ExtendedDllCharacteristicsChunk *extendedDllChars =
         make<ExtendedDllCharacteristicsChunk>(
             IMAGE_DLL_CHARACTERISTICS_EX_CET_COMPAT);
+    extendedDllChars->setAlignment(4);
     debugRecords.push_back(
         {COFF::IMAGE_DEBUG_TYPE_EX_DLLCHARACTERISTICS, extendedDllChars});
   }
 
   if (debugRecords.size() > 0) {
     for (std::pair<COFF::DebugType, Chunk *> r : debugRecords)
       debugInfoSec->addChunk(r.second);
   }