RFR: 8366092: [GCC static analyzer] UnixOperatingSystem.c warning: use of uninitialized value 'systemTicks' [v3]

[Matthias Baesken]

On Fri, 29 Aug 2025 14:11:01 GMT, Matthias Baesken <mbaesken at openjdk.org> wrote:

>> When using gcc static analyzer (-fanalyzer) with gcc 13.2 the following issue is reported :
>> 
>> /jdk/src/jdk.management/linux/native/libmanagement_ext/UnixOperatingSystem.c: In function 'get_jvmticks':
>> /jdk/src/jdk.management/linux/native/libmanagement_ext/UnixOperatingSystem.c:208:24: warning: use of uninitialized value 'systemTicks' [CWE-457] [-Wanalyzer-use-of-uninitialized-value]
>>   208 | pticks->usedKernel = systemTicks;
>> 
>> 
>> vsscanf usually/normally reads the systemTicks info from /proc file system. see
>> https://github.com/openjdk/jdk/blob/45726a1f8b8f76586037867a32b82f8ab9b96937/src/jdk.management/linux/native/libmanagement_ext/UnixOperatingSystem.c#L163
>> but we never check that the *exact* number of params is read with vsscanf :
>> n = vsscanf(tmp, fmt, args);
>> So potentially we could get a non complete info without systemTicks and the call would still succeed.
>
> Matthias Baesken has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Avoid initialization

Thanks for the reviews !

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PR Comment: https://git.openjdk.org/jdk/pull/26962#issuecomment-3241061930