Update comment: we don't allow NaN/(-)Infinity when invoking DoubleToAscii.
diff --git a/src/double-conversion.h b/src/double-conversion.h
index 10525d9..4d71d53 100644
--- a/src/double-conversion.h
+++ b/src/double-conversion.h
@@ -285,7 +285,8 @@
// should be at least kBase10MaximalLength + 1 characters long.
static const int kBase10MaximalLength = 17;
- // Converts the given double 'v' to ascii.
+ // Converts the given double 'v' to ascii. 'v' must not be NaN, +Infinity, or
+ // -Infinity.
// The result should be interpreted as buffer * 10^(point-length).
//
// The output depends on the given mode:
