Thread Expected<...> up from libObject’s getType() 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
section index is more than the number of sections.  The existing test case in test/Object/macho-invalid.test
for macho-invalid-section-index-getSectionRawName now reports the error with the message indicating
that a symbol at a specific index has a bad section index and that bad section 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.

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.

llvm-svn: 268298

1 files changed, 12 insertions, 3 deletions

diff --git a/llvm/tools/llvm-rtdyld/llvm-rtdyld.cpp b/llvm/tools/llvm-rtdyld/llvm-rtdyld.cpp
index d65fde1d696..7d302f1faed 100644
--- a/llvm/tools/llvm-rtdyld/llvm-rtdyld.cpp
+++ b/llvm/tools/llvm-rtdyld/llvm-rtdyld.cpp
@@ -335,9 +335,12 @@ static int printLineInfoForInput(bool LoadObjects, bool UseDebugObj) {
     // Use symbol info to iterate functions in the object.
     for (const auto &P : SymAddr) {
       object::SymbolRef Sym = P.first;
-      ErrorOr<SymbolRef::Type> TypeOrErr = Sym.getType();
-      if (!TypeOrErr)
+      Expected<SymbolRef::Type> TypeOrErr = Sym.getType();
+      if (!TypeOrErr) {
+        // TODO: Actually report errors helpfully.
+        consumeError(TypeOrErr.takeError());
         continue;
+      }
       SymbolRef::Type Type = *TypeOrErr;
       if (Type == object::SymbolRef::ST_Function) {
         Expected<StringRef> Name = Sym.getName();
@@ -356,7 +359,13 @@ static int printLineInfoForInput(bool LoadObjects, bool UseDebugObj) {
         // symbol in memory (rather than that in the unrelocated object file)
         // and use that to query the DWARFContext.
         if (!UseDebugObj && LoadObjects) {
-          object::section_iterator Sec = *Sym.getSection();
+          auto SecOrErr = Sym.getSection();
+          if (!SecOrErr) {
+            // TODO: Actually report errors helpfully.
+            consumeError(SecOrErr.takeError());
+            continue;
+          }
+          object::section_iterator Sec = *SecOrErr;
           StringRef SecName;
           Sec->getName(SecName);
           uint64_t SectionLoadAddress =