Add FIXMEs to all derived classes of std::error_category.

This helps make clear that we're moving away from std::error_code.

Differential Revision: http://reviews.llvm.org/D20592

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@270604 91177308-0d34-0410-b5e6-96231b3b80d8

Author: pcc

lib/Bitcode/Reader/BitcodeReader.cpp

@@ -6382,6 +6382,9 @@ std::error_code ModuleSummaryIndexBitcodeReader::initLazyStream(
 }
 
 namespace {
+// FIXME: This class is only here to support the transition to llvm::Error. It
+// will be removed once this transition is complete. Clients should prefer to
+// deal with the Error value directly, rather than converting to error_code.
 class BitcodeErrorCategoryType : public std::error_category {
   const char *name() const LLVM_NOEXCEPT override {
     return "llvm.bitcode";

lib/DebugInfo/PDB/DIA/DIAError.cpp

@@ -5,6 +5,9 @@
 using namespace llvm;
 using namespace llvm::pdb;
 
+// FIXME: This class is only here to support the transition to llvm::Error. It
+// will be removed once this transition is complete. Clients should prefer to
+// deal with the Error value directly, rather than converting to error_code.
 class DIAErrorCategory : public std::error_category {
 public:
   const char *name() const LLVM_NOEXCEPT override { return "llvm.pdb.dia"; }

lib/DebugInfo/PDB/GenericError.cpp

@@ -15,6 +15,9 @@ using namespace llvm;
 using namespace llvm::pdb;
 
 namespace {
+// FIXME: This class is only here to support the transition to llvm::Error. It
+// will be removed once this transition is complete. Clients should prefer to
+// deal with the Error value directly, rather than converting to error_code.
 class GenericErrorCategory : public std::error_category {
 public:
   const char *name() const LLVM_NOEXCEPT override { return "llvm.pdb"; }

lib/DebugInfo/PDB/Raw/RawError.cpp

@@ -6,6 +6,9 @@ using namespace llvm;
 using namespace llvm::pdb;
 
 namespace {
+// FIXME: This class is only here to support the transition to llvm::Error. It
+// will be removed once this transition is complete. Clients should prefer to
+// deal with the Error value directly, rather than converting to error_code.
 class RawErrorCategory : public std::error_category {
 public:
   const char *name() const LLVM_NOEXCEPT override { return "llvm.pdb.raw"; }

lib/ExecutionEngine/Orc/OrcError.cpp

@@ -20,6 +20,9 @@ using namespace llvm::orc;
 
 namespace {
 
+// FIXME: This class is only here to support the transition to llvm::Error. It
+// will be removed once this transition is complete. Clients should prefer to
+// deal with the Error value directly, rather than converting to error_code.
 class OrcErrorCategory : public std::error_category {
 public:
   const char *name() const LLVM_NOEXCEPT override { return "orc"; }

lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp

@@ -34,6 +34,9 @@ enum RuntimeDyldErrorCode {
   GenericRTDyldError = 1
 };
 
+// FIXME: This class is only here to support the transition to llvm::Error. It
+// will be removed once this transition is complete. Clients should prefer to
+// deal with the Error value directly, rather than converting to error_code.
 class RuntimeDyldErrorCategory : public std::error_category {
 public:
   const char *name() const LLVM_NOEXCEPT override { return "runtimedyld"; }

lib/Object/Error.cpp

@@ -19,6 +19,9 @@ using namespace llvm;
 using namespace object;
 
 namespace {
+// FIXME: This class is only here to support the transition to llvm::Error. It
+// will be removed once this transition is complete. Clients should prefer to
+// deal with the Error value directly, rather than converting to error_code.
 class _object_error_category : public std::error_category {
 public:
   const char* name() const LLVM_NOEXCEPT override;

lib/ProfileData/Coverage/CoverageMapping.cpp

@@ -556,6 +556,9 @@ std::string getCoverageMapErrString(coveragemap_error Err) {
   llvm_unreachable("A value of coveragemap_error has no message.");
 }
 
+// FIXME: This class is only here to support the transition to llvm::Error. It
+// will be removed once this transition is complete. Clients should prefer to
+// deal with the Error value directly, rather than converting to error_code.
 class CoverageMappingErrorCategoryType : public std::error_category {
   const char *name() const LLVM_NOEXCEPT override { return "llvm.coveragemap"; }
   std::string message(int IE) const override {

lib/ProfileData/InstrProf.cpp

@@ -67,6 +67,9 @@ std::string getInstrProfErrString(instrprof_error Err) {
   llvm_unreachable("A value of instrprof_error has no message.");
 }
 
+// FIXME: This class is only here to support the transition to llvm::Error. It
+// will be removed once this transition is complete. Clients should prefer to
+// deal with the Error value directly, rather than converting to error_code.
 class InstrProfErrorCategoryType : public std::error_category {
   const char *name() const LLVM_NOEXCEPT override { return "llvm.instrprof"; }
   std::string message(int IE) const override {

lib/ProfileData/SampleProf.cpp

@@ -20,6 +20,9 @@ using namespace llvm::sampleprof;
 using namespace llvm;
 
 namespace {
+// FIXME: This class is only here to support the transition to llvm::Error. It
+// will be removed once this transition is complete. Clients should prefer to
+// deal with the Error value directly, rather than converting to error_code.
 class SampleProfErrorCategoryType : public std::error_category {
   const char *name() const LLVM_NOEXCEPT override { return "llvm.sampleprof"; }
   std::string message(int IE) const override {