Removed potential buffer overrun (spotted by Neil Booth) when NumericLiteralParser
converts a parsed literal into an APFloat. We are still performing a copy of the
string, which hopefully will be removed eventually for performance reasons. This
version now is at least safe.
Changed rounding in APFloat construction in NumericLiteralParser from rmTowardsZero
to rmNearestTiesToEven.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@44422 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/Lex/LiteralSupport.cpp b/Lex/LiteralSupport.cpp
index ebc6627..f6d1a86 100644
--- a/Lex/LiteralSupport.cpp
+++ b/Lex/LiteralSupport.cpp
@@ -413,26 +413,21 @@
GetFloatValue(const llvm::fltSemantics &Format, bool* isExact) {
using llvm::APFloat;
- char floatChars[256];
- strncpy(floatChars, ThisTokBegin, ThisTokEnd-ThisTokBegin);
- floatChars[ThisTokEnd-ThisTokBegin] = '\0';
-
-#if 1
+ llvm::SmallVector<char,256> floatChars;
+ for (unsigned i = 0, n = ThisTokEnd-ThisTokBegin; i != n; ++i)
+ floatChars.push_back(ThisTokBegin[i]);
+
+ floatChars.push_back('\0');
+
APFloat V (Format, APFloat::fcZero, false);
-
APFloat::opStatus status;
- status = V.convertFromString(floatChars,APFloat::rmTowardZero);
+
+ status = V.convertFromString(&floatChars[0],APFloat::rmNearestTiesToEven);
if (isExact)
*isExact = status == APFloat::opOK;
return V;
-#else
- // FIXME: this is horrible!
- APFloat V(strtod(floatChars, 0));
- V.convert(Format, APFloat::rmTowardZero);
- return V;
-#endif
}
void NumericLiteralParser::Diag(SourceLocation Loc, unsigned DiagID,