Following changes in most recent FairLogger tag using string_view instead of string

[ehellbar]

FairLogger v2.1.0 introduces a new ("critical") severity to be used in O2. The previous FairLogger used was v1.11.1, so there were further changes in the meantime. One of them is changing std::string members to std::string_view members in https://github.com/FairRootGroup/FairLogger/blob/27527ad87b63213b7c58caf1e34a538e76f273da/logger/Logger.h#L176

This would also require a new InfoLogger tag, to be bumped together with FairLogger in alisw/alidist#5763

[ktf]

Does InfoLoggerMessageOption copy the string?

[sy-c]

No copy, InfoLoggerMessageOption is a POD with a char*. It's meant to be resolved at compile time whenever possible.

[ehellbar]

I replaced the char* in InfoLoggerMessageOption with a string_view, plus subsequent changes

[sy-c]

Hello @ehellbar,
thanks for the heads-up on the FMQ interface changes.
I prefer to avoid changes in the internal infoLogger structures, and limit the update to the FMQ external support file.

InfoLogger v2.8.0 now works fine with FMQLogger v2.1.0
940fefa

[ehellbar]

@sy-c thanks for taking care of it.

simply creating the string here 940fefa#diff-36584f894efde34aee0e3aedfd701712f9a7767d6bd748c11dc604bfd937d9acL94 was also my first thought. But @ktf reminded me that std::string(metadata.file) will go out of scope and the const char* of AliceO2::InfoLogger::InfoLogger::InfoLoggerMessageOption opt will point to something undefined. Or am I missing something different?

[sy-c]

You are right, sorry for this. Please use v2.8.1. #97

Valgrind did not complained in my tests, I guess the compiler optimized it as a singleton in the log() call - which is how it is usually written: InfoLoggerMessageOption directly set in the log() call without defining a variable. Here with the IF and two log() we indeed need the intermediate step.

[ehellbar]

I guess the compiler optimized it as a singleton in the log() call - which is how it is usually written: InfoLoggerMessageOption directly set in the log() call without defining a variable.

I see, thanks.