Handle 0 correctly in string->APFloat conversion.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@44594 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Support/APFloat.cpp b/lib/Support/APFloat.cpp
index b84f64a..d713223 100644
--- a/lib/Support/APFloat.cpp
+++ b/lib/Support/APFloat.cpp
@@ -2145,7 +2145,7 @@
            42039/12655 < L < 28738/8651  [ numerator <= 65536 ]
   */
 
-  if (*D.firstSigDigit == '0') {
+  if (*D.firstSigDigit == 0) {
     category = fcZero;
     fs = opOK;
   } else if ((D.normalizedExponent + 1) * 28738