- add .gnu.warning.SYMBOL support to ld.lld(1)

Index: lld/ELF/InputFiles.h
--- lld/ELF/InputFiles.h.orig
+++ lld/ELF/InputFiles.h
@@ -37,6 +37,8 @@ class DWARFCache;
 // Returns "<internal>", "foo.a(bar.o)" or "baz.o".
 std::string toString(const elf::InputFile *f);
 
+void parseGNUWarning(StringRef name, ArrayRef<char> data, size_t size);
+
 namespace elf {
 
 using llvm::object::Archive;