[LLD] [COFF] Autoexport symbols as data if they don't point to an executable section

[mstorsjo]

Summary

This was already taken care of for the output def file.

[ruiu]

LGTM

lld/trunk/COFF/Driver.cpp

if (Config->DLL && ((Config->MinGW && Config->Exports.empty()) ||
 
     Symtab->forEachSymbol([=](SymbolBody *S) {
       auto *Def = dyn_cast<Defined>(S);
       if (!Exporter.shouldExport(Def))
         return;
       Export E;
       E.Name = Def->getName();
       E.Sym = Def;
+      if (Def->getChunk() &&
+          !(Def->getChunk()->getPermissions() & IMAGE_SCN_MEM_EXECUTE))
+        E.Data = true;
       Config->Exports.push_back(E);
     });
   }
 
   // Windows specific -- when we are creating a .dll file, we also
   // need to create a .lib file.
   if (!Config->Exports.empty() || Config->DLL) {
     fixupExports();

lld/trunk/test/COFF/export-all.s

 # REQEUIRES: 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 | FileCheck %s
+# RUN: llvm-readobj %t.lib | FileCheck -check-prefix=IMPLIB %s
 
 # CHECK-NOT: Name: DllMainCRTStartup
+# CHECK: Name: dataSym
 # CHECK: Name: foobar
 
+# IMPLIB: Symbol: __imp__dataSym
+# IMPLIB-NOT: Symbol: _dataSym
+# IMPLIB: Symbol: __imp__foobar
+# IMPLIB: Symbol: _foobar
+
 .global _foobar
 .global _DllMainCRTStartup@12
+.global _dataSym
 .text
 _DllMainCRTStartup@12:
   ret
 _foobar:
   ret
+.data
+_dataSym:
+  .int 4
 
 # Test specifying -export-all-symbols, on an object file that contains
 # dllexport directive for some of the symbols.
 
 # RUN: yaml2obj < %p/Inputs/export.yaml > %t.obj
 #
 # RUN: lld-link -out:%t.dll -dll %t.obj -lldmingw -export-all-symbols -output-def:%t.def
 # RUN: llvm-readobj -coff-exports %t.dll | FileCheck -check-prefix=CHECK2 %s