[LLD] [COFF] Actually include the exported comdat symbols

[mstorsjo]

Summary

This is a followup to 2b01a417d7ccb001ccc1185ef5fdc967c9fac8d7;
previously the RVAs of the exported symbols from comdats were left
zero.

Thanks to Kleis Auke Wolthuizen for the fix suggestion and pointing
out the omission.

[mati865]

The change itself looks correct but cannot speak for the test.

[rnk]

lgtm

lld/COFF/Driver.cpp

for (auto *arg : args.filtered(OPT_wholearchive_file))
     if (Optional<StringRef> path = doFindFile(arg->getValue()))
       exporter.addWholeArchive(*path);
 
   symtab->forEachSymbol([&](Symbol *s) {
     auto *def = dyn_cast<Defined>(s);
     if (!exporter.shouldExport(def))
       return;
 
+    if (!def->isGCRoot) {
+      def->isGCRoot = true;
+      config->gcroot.push_back(def);
+    }
+
     Export e;
     e.name = def->getName();
     e.sym = def;
     if (Chunk *c = def->getChunk())
       if (!(c->getOutputCharacteristics() & IMAGE_SCN_MEM_EXECUTE))
         e.data = true;
     config->exports.push_back(e);
   });

lld/test/COFF/export-all.s

 # REQUIRES: x86
 
 # RUN: llvm-mc -triple=i686-windows-gnu %s -filetype=obj -o %t.obj
 
 # RUN: lld-link -lldmingw -dll -out:%t.dll -entry:DllMainCRTStartup@12 %t.obj -implib:%t.lib
 # RUN: llvm-readobj --coff-exports %t.dll | grep Name: | FileCheck %s
+# RUN: llvm-readobj --coff-exports %t.dll | FileCheck %s --check-prefix=CHECK-RVA
 # RUN: llvm-readobj %t.lib | FileCheck -check-prefix=IMPLIB %s
 
 # CHECK: Name:
 # CHECK-NEXT: Name: comdatFunc
 # CHECK-NEXT: Name: dataSym
 # CHECK-NEXT: Name: foobar
 # CHECK-EMPTY:
 
+# CHECK-RVA: Name: comdatFunc
+# CHECK-RVA-NEXT: RVA: 0x1003
+# CHECK-RVA: Name: dataSym
+# CHECK-RVA-NEXT: RVA: 0x3000
+# CHECK-RVA: Name: foobar
+# CHECK-RVA-NEXT: RVA: 0x1001
+
 # IMPLIB: Symbol: __imp__comdatFunc
 # IMPLIB: Symbol: _comdatFunc
 # IMPLIB: Symbol: __imp__dataSym
 # IMPLIB-NOT: Symbol: _dataSym
 # IMPLIB: Symbol: __imp__foobar
 # IMPLIB: Symbol: _foobar
 
 .global _foobar
 .global _DllMainCRTStartup@12
 .global _dataSym
 .global _unexported
 .global __imp__unexported
 .global .refptr._foobar
 .global _comdatFunc
 .text
 _DllMainCRTStartup@12:
   ret
 _foobar:
   ret
 _unexported:
   ret
-.section .text@_comdatFunc,"xr",one_only,_comdatFunc
+.section .text$_comdatFunc,"xr",one_only,_comdatFunc
 _comdatFunc:
   ret
 .data
 _dataSym:
   .int 4
 __imp__unexported:
   .int _unexported
 .refptr._foobar: