math: Fix UB in ldbl-128 setpayload

UBSAN: Undefined behaviour in ../sysdeps/ieee754/float128/../ldbl-128/s_setpayloadl_main.c:47:34 shift exponent 16431 is too large for 64-bit type 'long long unsigned int'

diff --git a/sysdeps/ieee754/ldbl-128/s_setpayloadl_main.c b/sysdeps/ieee754/ldbl-128/s_setpayloadl_main.c
index f106ede9a4ea1acacc860ca643366749f03039db..377428d1aaf22410ab94e955779fef99f70cce93 100644 (file)
--- a/sysdeps/ieee754/ldbl-128/s_setpayloadl_main.c
+++ b/sysdeps/ieee754/ldbl-128/s_setpayloadl_main.c
@@ -44,7 +44,8 @@ FUNC (_Float128 *x, _Float128 payload)
   int shift = BIAS + EXPLICIT_MANT_DIG - exponent;
   if (shift < 64
       ? (lx & ((1ULL << shift) - 1)) != 0
-      : (lx != 0 || (hx & ((1ULL << (shift - 64)) - 1)) != 0))
+      : (shift < 128
+        && (lx != 0 || (hx & ((1ULL << (shift - 64)) - 1)) != 0)))
     {
       SET_LDOUBLE_WORDS64 (*x, 0, 0);
       return 1;