lld-link: Also demangle undefined dllimported symbols.

dllimported symbols go through an import stub that's called __imp_ followed by
the name the stub points to. Make that work.

Differential Revision: https://reviews.llvm.org/D52145

llvm-svn: 342401

1 files changed, 7 insertions, 1 deletions

diff --git a/lld/Common/Strings.cpp b/lld/Common/Strings.cpp
index 581a0795482..6f74865b7f4 100644
--- a/lld/Common/Strings.cpp
+++ b/lld/Common/Strings.cpp
@@ -38,14 +38,20 @@ Optional<std::string> lld::demangleItanium(StringRef Name) {
 }
 
 Optional<std::string> lld::demangleMSVC(StringRef Name) {
+  std::string Prefix;
+  if (Name.consume_front("__imp_"))
+    Prefix = "__declspec(dllimport) ";
+
+  // Demangle only C++ names.
   if (!Name.startswith("?"))
     return None;
+
   char *Buf = microsoftDemangle(Name.str().c_str(), nullptr, nullptr, nullptr);
   if (!Buf)
     return None;
   std::string S(Buf);
   free(Buf);
-  return S;
+  return Prefix + S;
 }
 
 StringMatcher::StringMatcher(ArrayRef<StringRef> Pat) {