Make it explicit that nulls are not allowed in names.

The object files we support use null terminated strings, so there is no way to
support these.

This patch adds an assert to catch bad API use and an error check in the .ll
parser.

llvm-svn: 195155

2 files changed, 6 insertions, 0 deletions

diff --git a/llvm/lib/AsmParser/LLLexer.cpp b/llvm/lib/AsmParser/LLLexer.cpp
index 1e6085b443f..3c384f5fcca 100644
--- a/llvm/lib/AsmParser/LLLexer.cpp
+++ b/llvm/lib/AsmParser/LLLexer.cpp
@@ -275,6 +275,10 @@ lltok::Kind LLLexer::LexAt() {
       if (CurChar == '"') {
         StrVal.assign(TokStart+2, CurPtr-1);
         UnEscapeLexed(StrVal);
+        if (StringRef(StrVal).find_first_of(0) != StringRef::npos) {
+          Error("Null bytes are not allowed in names");
+          return lltok::Error;
+        }
         return lltok::GlobalVar;
       }
     }
diff --git a/llvm/lib/IR/Value.cpp b/llvm/lib/IR/Value.cpp
index 62a3b31c18b..2c90383edd8 100644
--- a/llvm/lib/IR/Value.cpp
+++ b/llvm/lib/IR/Value.cpp
@@ -182,6 +182,8 @@ void Value::setName(const Twine &NewName) {
 
   SmallString<256> NameData;
   StringRef NameRef = NewName.toStringRef(NameData);
+  assert(NameRef.find_first_of(0) == StringRef::npos &&
+         "Null bytes are not allowed in names");
 
   // Name isn't changing?
   if (getName() == NameRef)