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, 15 insertions, 8 deletions

diff --git a/llvm/tools/llvm-nm/llvm-nm.cpp b/llvm/tools/llvm-nm/llvm-nm.cpp
index 05ebc44ff83..4c0d7535ec2 100644
--- a/llvm/tools/llvm-nm/llvm-nm.cpp
+++ b/llvm/tools/llvm-nm/llvm-nm.cpp
@@ -373,9 +373,10 @@ static void darwinPrintSymbol(SymbolicFile &Obj, SymbolListT::iterator I,
         outs() << "(?,?) ";
       break;
     }
-    ErrorOr<section_iterator> SecOrErr =
+    Expected<section_iterator> SecOrErr =
       MachO->getSymbolSection(I->Sym.getRawDataRefImpl());
-    if (SecOrErr.getError()) {
+    if (!SecOrErr) {
+      consumeError(SecOrErr.takeError());
       outs() << "(?,?) ";
       break;
     }
@@ -697,9 +698,11 @@ static char getSymbolNMTypeChar(ELFObjectFileBase &Obj,
   // OK, this is ELF
   elf_symbol_iterator SymI(I);
 
-  ErrorOr<elf_section_iterator> SecIOrErr = SymI->getSection();
-  if (error(SecIOrErr.getError()))
+  Expected<elf_section_iterator> SecIOrErr = SymI->getSection();
+  if (!SecIOrErr) {
+    consumeError(SecIOrErr.takeError());
     return '?';
+  }
 
   elf_section_iterator SecI = *SecIOrErr;
   if (SecI != Obj.section_end()) {
@@ -759,9 +762,11 @@ static char getSymbolNMTypeChar(COFFObjectFile &Obj, symbol_iterator I) {
 
   uint32_t Characteristics = 0;
   if (!COFF::isReservedSectionNumber(Symb.getSectionNumber())) {
-    ErrorOr<section_iterator> SecIOrErr = SymI->getSection();
-    if (error(SecIOrErr.getError()))
+    Expected<section_iterator> SecIOrErr = SymI->getSection();
+    if (!SecIOrErr) {
+      consumeError(SecIOrErr.takeError());
       return '?';
+    }
     section_iterator SecI = *SecIOrErr;
     const coff_section *Section = Obj.getCOFFSection(*SecI);
     Characteristics = Section->Characteristics;
@@ -802,9 +807,11 @@ static char getSymbolNMTypeChar(MachOObjectFile &Obj, basic_symbol_iterator I) {
   case MachO::N_INDR:
     return 'i';
   case MachO::N_SECT: {
-    ErrorOr<section_iterator> SecOrErr = Obj.getSymbolSection(Symb);
-    if (SecOrErr.getError())
+    Expected<section_iterator> SecOrErr = Obj.getSymbolSection(Symb);
+    if (!SecOrErr) {
+      consumeError(SecOrErr.takeError());
       return 's';
+    }
     section_iterator Sec = *SecOrErr;
     DataRefImpl Ref = Sec->getRawDataRefImpl();
     StringRef SectionName;