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The risk of introducing a problem might be quite low here, but in general it exists: With the adjustment you remove any chance of the compiler spotting a missing initialization before use. And I'm not convinced using 0 in such a case would actually be ending up sufficiently benign. Jan > --- a/arch/x86/xen/pmu.c > +++ b/arch/x86/xen/pmu.c > @@ -302,7 +302,7 @@ static bool xen_amd_pmu_emulate(unsigned int msr, u64 *val, bool is_read) > static bool pmu_msr_chk_emulated(unsigned int msr, uint64_t *val, bool is_read, > bool *emul) > { > - int type, index; > + int type = 0, index = 0; > > if (is_amd_pmu_msr(msr)) > *emul = xen_amd_pmu_emulate(msr, val, is_read);