Harden Lexer::GetBeginningOfToken() against bogus source locations and
the disappearance/alteration of files.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@124616 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Lex/Lexer.cpp b/lib/Lex/Lexer.cpp
index 5d9536f..7c94528 100644
--- a/lib/Lex/Lexer.cpp
+++ b/lib/Lex/Lexer.cpp
@@ -357,6 +357,9 @@
const SourceManager &SM,
const LangOptions &LangOpts) {
std::pair<FileID, unsigned> LocInfo = SM.getDecomposedLoc(Loc);
+ if (LocInfo.first.isInvalid())
+ return Loc;
+
bool Invalid = false;
llvm::StringRef Buffer = SM.getBufferData(LocInfo.first, &Invalid);
if (Invalid)
@@ -365,6 +368,9 @@
// Back up from the current location until we hit the beginning of a line
// (or the buffer). We'll relex from that point.
const char *BufStart = Buffer.data();
+ if (LocInfo.second >= Buffer.size())
+ return Loc;
+
const char *StrData = BufStart+LocInfo.second;
if (StrData[0] == '\n' || StrData[0] == '\r')
return Loc;