Re: [PATCH 02/10] tools/libxg: Fix uninitialised variable in write_x86_cpu_policy_records()

[Jan Beulich <jbeulich@xxxxxxxx>]

On 12.02.2021 16:39, Andrew Cooper wrote:
> Various version of gcc, when compiling with -Og, complain:
> 
>   xg_sr_common_x86.c: In function 'write_x86_cpu_policy_records':
>   xg_sr_common_x86.c:92:12: error: 'rc' may be used uninitialized in this 
> function [-Werror=maybe-uninitialized]
>      92 |     return rc;
>         |            ^~
> 
> The complaint is legitimate, and can occur with unexpected behaviour of two
> related hypercalls in combination with a libc which permits zero-length
> malloc()s.
> 
> Have an explicit rc = 0 on the success path, and make the MSRs record error
> handling consistent with the CPUID record before it.
> 
> Fixes: f6b2b8ec53d ("libxc/save: Write X86_{CPUID,MSR}_DATA records")
> Signed-off-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>

Reviewed-by: Jan Beulich <jbeulich@xxxxxxxx>