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Re: InfiniBand-ocrdma: Delete unnecessary variable initialisations in 11 functions

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> GCC supported it before 1999 when I saw it first time. My assumption
> that in 2016 all compilers are doing such optimization now.

Interesting …


> I would be glad to hear an example of modern compiler which doesn't
> support this simple optimization.

Would you like to take into account any other source code analysis approaches?


>> Will any configuration parameters and command arguments become relevant
>> to improve also a corresponding software comparison?
> 
> Please suggest us, you are proposing this change, and not me.

Which combination of hardware and software versions would you find representative
for a corresponding system check?


>>> The proposed change won't affect performance at all.
>>
>> Will unneeded variable assignments be really optimised away by default?
> 
> Yes

Can it be that this result will depend on special parameters so that data flow
analysis and optimisation will be performed in the way you seem to expect?


> If you are interested in saving space of one latter, you need to take into
> account git database increase, do you?

There are also other aspects to consider:

* Do you insist to initialise a return code at the beginning of every function
  with a non-void return type?

* Does each bit of extra information can result also in unwanted consequences?

* Is this a specific source code review concern?

* Can this software be improved a bit more only if we dare to talk about
  potential update candidates?

Regards,
Markus

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[PATCH v3 0/6] InfiniBand-ocrdma: Fine-tuning for some function  implementations SF Markus Elfring <elfring@users.sourceforge.net> - 2016-01-14 18:20 +0100
  [PATCH v3 1/6] InfiniBand-ocrdma: One jump label less in  ocrdma_alloc_ucontext_pd() SF Markus Elfring <elfring@users.sourceforge.net> - 2016-01-14 18:40 +0100
  [PATCH v3 3/6] InfiniBand-ocrdma: Returning only value constants in  ocrdma_qp_state_change() SF Markus Elfring <elfring@users.sourceforge.net> - 2016-01-14 18:50 +0100
  [PATCH v3 2/6] InfiniBand-ocrdma: Delete unnecessary variable  initialisations in 11 functions SF Markus Elfring <elfring@users.sourceforge.net> - 2016-01-14 18:50 +0100
    Re: [PATCH v3 2/6] InfiniBand-ocrdma: Delete unnecessary variable  initialisations in 11 functions Leon Romanovsky <leon@leon.nu> - 2016-01-15 14:30 +0100
      Re: InfiniBand-ocrdma: Delete unnecessary variable initialisations in  11 functions SF Markus Elfring <elfring@users.sourceforge.net> - 2016-01-15 16:00 +0100
        Re: InfiniBand-ocrdma: Delete unnecessary variable initialisations  in 11 functions Leon Romanovsky <leon@leon.nu> - 2016-01-15 16:10 +0100
          Re: InfiniBand-ocrdma: Delete unnecessary variable initialisations in  11 functions SF Markus Elfring <elfring@users.sourceforge.net> - 2016-01-15 16:30 +0100
            Re: InfiniBand-ocrdma: Delete unnecessary variable initialisations  in 11 functions Leon Romanovsky <leon@leon.nu> - 2016-01-15 17:00 +0100
              Re: InfiniBand-ocrdma: Delete unnecessary variable initialisations  in 11 functions Dan Carpenter <dan.carpenter@oracle.com> - 2016-01-15 17:20 +0100
              Re: InfiniBand-ocrdma: Delete unnecessary variable initialisations in  11 functions SF Markus Elfring <elfring@users.sourceforge.net> - 2016-01-15 17:30 +0100
                Re: InfiniBand-ocrdma: Delete unnecessary variable initialisations  in 11 functions Leon Romanovsky <leon@leon.nu> - 2016-01-15 18:10 +0100
                Re: InfiniBand-ocrdma: Delete unnecessary variable initialisations  in 11 functions Leon Romanovsky <leon@leon.nu> - 2016-01-15 18:50 +0100
                Re: InfiniBand-ocrdma: Delete unnecessary variable initialisations in  11 functions SF Markus Elfring <elfring@users.sourceforge.net> - 2016-01-15 19:30 +0100
                Re: InfiniBand-ocrdma: Delete unnecessary variable initialisations  in 11 functions Leon Romanovsky <leon@leon.nu> - 2016-01-16 07:20 +0100
                Re: InfiniBand-ocrdma: Delete unnecessary variable initialisations in  11 functions SF Markus Elfring <elfring@users.sourceforge.net> - 2016-01-16 09:40 +0100
  [PATCH v3 4/6] InfiniBand-ocrdma: Return a value from a function call  in _ocrdma_modify_qp() directly SF Markus Elfring <elfring@users.sourceforge.net> - 2016-01-14 18:50 +0100
  [PATCH v3 6/6] InfiniBand-ocrdma: Delete an unnecessary variable in  ocrdma_dealloc_pd() SF Markus Elfring <elfring@users.sourceforge.net> - 2016-01-14 19:00 +0100
  [PATCH v3 5/6] InfiniBand-ocrdma: Returning only value constants in  ocrdma_resize_cq() SF Markus Elfring <elfring@users.sourceforge.net> - 2016-01-14 19:00 +0100

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