[WebAssembly] Fix build after rL355577

[sbc100]

Summary

Turns own that IsUsedInRegularObject is set for lazy (archive) symbols.

[pcc]

Turns own that IsUsedInRegularObject is set for lazy (archive) symbols.

Should we fix that, then?

[sbc100]

In D59074#1421058, @pcc wrote:

Turns own that IsUsedInRegularObject is set for lazy (archive) symbols.

Should we fix that, then?

It correct according to the comment in ELF/Symbols.h:

// True if the symbol was used for linking and thus need to be added to the    
// output file's symbol table. This is true for all symbols except for         
// unreferenced DSO symbols and bitcode symbols that are unreferenced except   
// by other bitcode objects.                                                   
unsigned IsUsedInRegularObj : 1;

I guess objects in archives are still regular objects.

[sbc100]

In D59074#1421059, @sbc100 wrote:

In D59074#1421058, @pcc wrote:

Turns own that IsUsedInRegularObject is set for lazy (archive) symbols.

Should we fix that, then?

It correct according to the comment in ELF/Symbols.h:

// True if the symbol was used for linking and thus need to be added to the    
// output file's symbol table. This is true for all symbols except for         
// unreferenced DSO symbols and bitcode symbols that are unreferenced except   
// by other bitcode objects.                                                   
unsigned IsUsedInRegularObj : 1;

I guess objects in archives are still regular objects.

Looks like the comment is wrong though.. so fixing: https://reviews.llvm.org/D59075

lld/wasm/Writer.cpp

auto AddSymbol = [&](Symbol *Sym) {
     // (Since this is relocatable output, GC is not performed so symbols must
     // be live.)
     assert(Sym->isLive());
     Sym->setOutputSymbolIndex(SymbolIndex++);
     SymtabEntries.emplace_back(Sym);
   };
 
   for (Symbol *Sym : Symtab->getSymbols())
-    if (Sym->IsUsedInRegularObj)
+    if (!Sym->isLazy() && Sym->IsUsedInRegularObj)
       AddSymbol(Sym);
 
   for (ObjFile *File : Symtab->ObjectFiles) {
     LLVM_DEBUG(dbgs() << "Local symtab entries: " << File->getName() << "\n");
     for (Symbol *Sym : File->getSymbols())
       if (Sym->isLocal())
         AddSymbol(Sym);
   }