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lib/Bitcode/NaCl/Reader/NaClBitcodeReader.cpp

Index: lib/Bitcode/NaCl/Reader/NaClBitcodeReader.cpp
diff --git a/lib/Bitcode/NaCl/Reader/NaClBitcodeReader.cpp b/lib/Bitcode/NaCl/Reader/NaClBitcodeReader.cpp
index 8b8e9072a877a65c90b20a49847815d08669417f..1052707b03320882251d0d187b13aca6aafa5eeb 100644
--- a/lib/Bitcode/NaCl/Reader/NaClBitcodeReader.cpp
+++ b/lib/Bitcode/NaCl/Reader/NaClBitcodeReader.cpp
@@ -986,7 +986,7 @@ bool NaClBitcodeReader::ParseBitcodeInto(Module *M) {
   M->setDataLayout("e-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-"
                    "f32:32:32-f64:64:64-p:32:32:32-v128:32:32");
 
-  if (InitStream()) return Error(Header.Unsupported());
+  if (InitStream()) return true; // InitSream will set the error string.
 
   // We expect a number of well-defined blocks, though we don't necessarily
   // need to understand them all.
@@ -1758,7 +1758,8 @@ bool NaClBitcodeReader::InitStreamFromBuffer() {
   StreamFile.reset(new NaClBitstreamReader(BufPtr, BufEnd));
   Stream.init(*StreamFile);
 
-  return AcceptHeader();
+  if (AcceptHeader())

[jvoung (off chromium), 2013/09/09 23:47:53]

Not quite sure the difference in when "return Error(...)" happens.    Doesn't it
just set a field that will be read later (so doesn't matter too much when it
happens)?

You also have to return a value AcceptHeader() returns no error?

[Derek Schuff, 2013/09/10 18:40:23]

Error just sets a field that will be read later. But Unsupported was only set
when the header is valid but the version is unsupported, so as it was,
InitLazyStream was setting the error on line 1786 but ParseBitcodeInto was
overwriting it. Since InitStream and its callees still set the error, I've kept
this, but also improved the error messages they set.

+    return Error(Header.Unsupported());
 }
 
 bool NaClBitcodeReader::InitLazyStream() {
@@ -1768,7 +1769,8 @@ bool NaClBitcodeReader::InitLazyStream() {
 
   StreamFile.reset(new NaClBitstreamReader(Bytes, Header.getHeaderSize()));
   Stream.init(*StreamFile);
-  return AcceptHeader();
+  if (AcceptHeader())
+    return Error(Header.Unsupported());
 }
 
 //===----------------------------------------------------------------------===//