Thread Expected<...> up from libObject’s getName() for symbols to allow llvm-objdump to produce a good error message.

Produce another specific error message for a malformed Mach-O file when a symbol’s
string index is past the end of the string table.  The existing test case in test/Object/macho-invalid.test
for macho-invalid-symbol-name-past-eof now reports the error with the message indicating
that a symbol at a specific index has a bad sting index and that bad string index value.
 
Again converting interfaces to Expected<> from ErrorOr<> does involve
touching a number of places. Where the existing code reported the error with a
string message or an error code it was converted to do the same.  There is some
code for this that could be factored into a routine but I would like to leave that for
the code owners post-commit to do as they want for handling an llvm::Error.  An
example of how this could be done is shown in the diff in
lib/ExecutionEngine/RuntimeDyld/RuntimeDyldImpl.h which had a Check() routine
already for std::error_code so I added one like it for llvm::Error .

Also there some were bugs in the existing code that did not deal with the
old ErrorOr<> return values.  So now with Expected<> since they must be
checked and the error handled, I added a TODO and a comment:
“// TODO: Actually report errors helpfully” and a call something like
consumeError(NameOrErr.takeError()) so the buggy code will not crash
since needed to deal with the Error.

Note there fixes needed to lld that goes along with this that I will commit right after this.
So expect lld not to built after this commit and before the next one.

llvm-svn: 266919

1 files changed, 6 insertions, 6 deletions

diff --git a/llvm/tools/llvm-cxxdump/llvm-cxxdump.cpp b/llvm/tools/llvm-cxxdump/llvm-cxxdump.cpp
index 5048987865f..dc1cc23c232 100644
--- a/llvm/tools/llvm-cxxdump/llvm-cxxdump.cpp
+++ b/llvm/tools/llvm-cxxdump/llvm-cxxdump.cpp
@@ -79,8 +79,8 @@ static void collectRelocatedSymbols(const ObjectFile *Obj,
       const object::symbol_iterator RelocSymI = Reloc.getSymbol();
       if (RelocSymI == Obj->symbol_end())
         continue;
-      ErrorOr<StringRef> RelocSymName = RelocSymI->getName();
-      error(RelocSymName.getError());
+      Expected<StringRef> RelocSymName = RelocSymI->getName();
+      error(errorToErrorCode(RelocSymName.takeError()));
       uint64_t Offset = Reloc.getOffset();
       if (Offset >= SymOffset && Offset < SymEnd) {
         *I = *RelocSymName;
@@ -101,8 +101,8 @@ static void collectRelocationOffsets(
       const object::symbol_iterator RelocSymI = Reloc.getSymbol();
       if (RelocSymI == Obj->symbol_end())
         continue;
-      ErrorOr<StringRef> RelocSymName = RelocSymI->getName();
-      error(RelocSymName.getError());
+      Expected<StringRef> RelocSymName = RelocSymI->getName();
+      error(errorToErrorCode(RelocSymName.takeError()));
       uint64_t Offset = Reloc.getOffset();
       if (Offset >= SymOffset && Offset < SymEnd)
         Collection[std::make_pair(SymName, Offset - SymOffset)] = *RelocSymName;
@@ -175,8 +175,8 @@ static void dumpCXXData(const ObjectFile *Obj) {
   for (auto &P : SymAddr) {
     object::SymbolRef Sym = P.first;
     uint64_t SymSize = P.second;
-    ErrorOr<StringRef> SymNameOrErr = Sym.getName();
-    error(SymNameOrErr.getError());
+    Expected<StringRef> SymNameOrErr = Sym.getName();
+    error(errorToErrorCode(SymNameOrErr.takeError()));
     StringRef SymName = *SymNameOrErr;
     ErrorOr<object::section_iterator> SecIOrErr = Sym.getSection();
     error(SecIOrErr.getError());