[llvm] r258298 - [LTO] Fix error reporting when a file passed to libLTO is invalid or non-existent

[Petr Pavlu via llvm-commits]

Author: petr.pavlu
Date: Wed Jan 20 03:03:42 2016
New Revision: 258298

URL: http://llvm.org/viewvc/llvm-project?rev=258298&view=rev
Log:
[LTO] Fix error reporting when a file passed to libLTO is invalid or non-existent

This addresses PR26060 where function lto_module_create() could return nullptr
but lto_get_error_message() returned an empty string.

The error() call after LTOModule::createFromFile() in llvm-lto is then removed
because any error from this function should go through the diagnostic handler in
llvm-lto which will exit the program. The error() call was added because this
previously did not happen when the file was non-existent. This is fixed by the
patch. (The situation that llvm-lto reports an error when the input file does
not exist is tested by llvm/tools/llvm-lto/error.ll).

Differential Revision: http://reviews.llvm.org/D16106

Modified:
    llvm/trunk/lib/LTO/LTOModule.cpp
    llvm/trunk/tools/llvm-lto/llvm-lto.cpp
    llvm/trunk/tools/lto/lto.cpp

Modified: llvm/trunk/lib/LTO/LTOModule.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/LTO/LTOModule.cpp?rev=258298&r1=258297&r2=258298&view=diff
==============================================================================
--- llvm/trunk/lib/LTO/LTOModule.cpp (original)
+++ llvm/trunk/lib/LTO/LTOModule.cpp Wed Jan 20 03:03:42 2016
@@ -105,8 +105,10 @@ LTOModule::createFromFile(LLVMContext &C
                           TargetOptions options) {
   ErrorOr<std::unique_ptr<MemoryBuffer>> BufferOrErr =
       MemoryBuffer::getFile(path);
-  if (std::error_code EC = BufferOrErr.getError())
+  if (std::error_code EC = BufferOrErr.getError()) {
+    Context.emitError(EC.message());
     return EC;
+  }
   std::unique_ptr<MemoryBuffer> Buffer = std::move(BufferOrErr.get());
   return makeLTOModule(Buffer->getMemBufferRef(), options, &Context);
 }
@@ -123,8 +125,10 @@ LTOModule::createFromOpenFileSlice(LLVMC
                                    off_t offset, TargetOptions options) {
   ErrorOr<std::unique_ptr<MemoryBuffer>> BufferOrErr =
       MemoryBuffer::getOpenFileSlice(fd, path, map_size, offset);
-  if (std::error_code EC = BufferOrErr.getError())
+  if (std::error_code EC = BufferOrErr.getError()) {
+    Context.emitError(EC.message());
     return EC;
+  }
   std::unique_ptr<MemoryBuffer> Buffer = std::move(BufferOrErr.get());
   return makeLTOModule(Buffer->getMemBufferRef(), options, &Context);
 }
@@ -158,8 +162,10 @@ parseBitcodeFileImpl(MemoryBufferRef Buf
   // Find the buffer.
   ErrorOr<MemoryBufferRef> MBOrErr =
       IRObjectFile::findBitcodeInMemBuffer(Buffer);
-  if (std::error_code EC = MBOrErr.getError())
+  if (std::error_code EC = MBOrErr.getError()) {
+    Context.emitError(EC.message());
     return EC;
+  }
 
   if (!ShouldBeLazy) {
     // Parse the full file.

Modified: llvm/trunk/tools/llvm-lto/llvm-lto.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/tools/llvm-lto/llvm-lto.cpp?rev=258298&r1=258297&r2=258298&view=diff
==============================================================================
--- llvm/trunk/tools/llvm-lto/llvm-lto.cpp (original)
+++ llvm/trunk/tools/llvm-lto/llvm-lto.cpp Wed Jan 20 03:03:42 2016
@@ -294,7 +294,6 @@ int main(int argc, char **argv) {
     CurrentActivity = "loading file '" + InputFilenames[i] + "'";
     ErrorOr<std::unique_ptr<LTOModule>> ModuleOrErr =
         LTOModule::createFromFile(Context, InputFilenames[i].c_str(), Options);
-    error(ModuleOrErr, "error " + CurrentActivity);
     std::unique_ptr<LTOModule> &Module = *ModuleOrErr;
     CurrentActivity = "";
 

Modified: llvm/trunk/tools/lto/lto.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/tools/lto/lto.cpp?rev=258298&r1=258297&r2=258298&view=diff
==============================================================================
--- llvm/trunk/tools/lto/lto.cpp (original)
+++ llvm/trunk/tools/lto/lto.cpp Wed Jan 20 03:03:42 2016
@@ -81,7 +81,6 @@ static void diagnosticHandler(const Diag
     DiagnosticPrinterRawOStream DP(Stream);
     DI.print(DP);
   }
-  sLastErrorString += '\n';
 }
 
 // Initialize the configured targets if they have not been initialized.
@@ -111,7 +110,6 @@ namespace {
 static void handleLibLTODiagnostic(lto_codegen_diagnostic_severity_t Severity,
                                    const char *Msg, void *) {
   sLastErrorString = Msg;
-  sLastErrorString += "\n";
 }
 
 // This derived class owns the native object file. This helps implement the