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x86: Fix UB in x86_cpu_present/x86_cpu_active 

The elf/tst-cpu-features-supports (and other tests that check for
CPU features) triggers the following issue with ubsan:

UBSAN: Undefined behaviour in ../sysdeps/x86/sys/platform/x86.h:59:42 left shift of 1 by 31 cannot be represented in type 'int'

The active_array is unsigned, so use an unsigned constant as well.
This commit is contained in:
Adhemerval Zanella 2025-04-18 09:52:04 -03:00
parent 8cc687cbac
commit 7417fcf25a
1 changed files with 2 additions and 2 deletions
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4
sysdeps/x86/sys/platform/x86.h
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@ -40,7 +40,7 @@ x86_cpu_present (unsigned int __index)
unsigned int __bit = __reg & (8 * sizeof (unsigned int) - 1);
__reg /= 8 * sizeof (unsigned int);
return __ptr->cpuid_array[__reg] & (1 << __bit);
return __ptr->cpuid_array[__reg] & (1U << __bit);
}
static __inline__ bool
@ -56,7 +56,7 @@ x86_cpu_active (unsigned int __index)
unsigned int __bit = __reg & (8 * sizeof (unsigned int) - 1);
__reg /= 8 * sizeof (unsigned int);
return __ptr->active_array[__reg] & (1 << __bit);
return __ptr->active_array[__reg] & (1U << __bit);
}
/* CPU_FEATURE_PRESENT evaluates to true if CPU supports the feature. */