@@ -137,9 +137,18 @@ __expm1l (long double x)
if (x < minarg)
return (4.0/big - 1.0L);
- /* Avoid internal underflow when result does not underflow. */
- if (fabsl (x) < 0x1p-113L && fabsl (x) >= LDBL_MIN)
- return x;
+ /* Avoid internal underflow when result does not underflow, while
+ ensuring underflow (without returning a zero of the wrong sign)
+ when the result does underflow. */
+ if (fabsl (x) < 0x1p-113L)
+ {
+ if (fabsl (x) < LDBL_MIN)
+ {
+ long double force_underflow = x * x;
+ math_force_eval (force_underflow);
+ }
+ return x;
+ }
/* Express x = ln 2 (k + remainder), remainder not exceeding 1/2. */
xx = C1 + C2; /* ln 2. */