[PATCH 5/8] math: Fix UB on cbrtf
Adhemerval Zanella
adhemerval.zanella@linaro.org
Fri Apr 25 20:54:26 GMT 2025
The left shift overflows for 'int64_t', use unsigned instead. It syncs
with CORE-MATH commit f7c7408d1749ec2859ea249495af699359ae559b.
Checked on aarch64-linux-gnu, x86_64-linux-gnu, and i686-linux-gnu.
---
sysdeps/ieee754/flt-32/s_cbrtf.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/sysdeps/ieee754/flt-32/s_cbrtf.c b/sysdeps/ieee754/flt-32/s_cbrtf.c
index 5a7a9a952d..df9e888c1f 100644
--- a/sysdeps/ieee754/flt-32/s_cbrtf.c
+++ b/sysdeps/ieee754/flt-32/s_cbrtf.c
@@ -3,7 +3,7 @@
Copyright (c) 2023, 2024 Alexei Sibidanov.
The original version of this file was copied from the CORE-MATH
-project (file src/binary32/cbrt/cbrtf.c, revision bc385c2).
+project (file src/binary32/cbrt/cbrtf.c, revision f7c7408d).
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
@@ -61,8 +61,8 @@ __cbrtf (float x)
e += 899;
uint32_t et = e / 3, it = e % 3;
uint64_t isc = escale[it].u;
- isc += (int64_t) (et - 342) << 52;
- isc |= (int64_t) sgn << 63;
+ isc += (uint64_t) (et - 342) << 52;
+ isc |= (uint64_t) sgn << 63;
double cvt2 = asdouble (isc);
static const double c[] =
{
--
2.43.0
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