From: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Date: Tue, 6 May 2025 13:38:31 +0000 (+0000)
Subject: math: Fix UB on dbl-64 rint
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=ae54df4654944360f7c0c298a3db3706cc0e8d42;p=thirdparty%2Fglibc.git

math: Fix UB on dbl-64 rint

UBSAN: Undefined behaviour in ../sysdeps/ieee754/dbl-64/s_rint.c:53:4 left shift of 1 by 63 cannot be represented in type 'long long int'
---

diff --git a/sysdeps/ieee754/dbl-64/s_rint.c b/sysdeps/ieee754/dbl-64/s_rint.c
index 8604733ef9..450d886655 100644
--- a/sysdeps/ieee754/dbl-64/s_rint.c
+++ b/sysdeps/ieee754/dbl-64/s_rint.c
@@ -37,7 +37,8 @@ __rint (double x)
 		4.50359962737049600000e+15, /* 0x43300000, 0x00000000 */
 		-4.50359962737049600000e+15, /* 0xC3300000, 0x00000000 */
   };
-  int64_t i0, sx;
+  int64_t i0;
+  uint64_t sx;
   int32_t j0;
   EXTRACT_WORDS64 (i0, x);
   sx = (i0 >> 63) & 1;