Re: [Boost-users] Static linking/GCC 4.3.2 on Linux (-fPIC missing?)

Subject: Re: [Boost-users] Static linking/GCC 4.3.2 on Linux (-fPIC missing?)
From: Vladimir Prus (vladimir_at_[hidden])
Date: 2009-03-09 18:01:35

Ravi wrote:

> On Sunday 08 March 2009 01:47:52 Vladimir Prus wrote:
>> Or are there any negative effects by enabling -fPIC?
>>
>> -fPIC generates slower code. I am not aware of up-to-date data on how much
>> slower.
> 
> On my numerically intensive software, -fPIC does not lead to any measurable
> slowdowns. Another data point comes from ATLAS (whose sole raison d'etre is
> speed in numerical computations) in its INSTALL.txt file:
> ---
> NOTE: Since gcc uses one less int register when compiling with this flag, this
>       could potentially impact performance of the architectural defaults,
>       but we have not seen it so far.
> ---
> 
> However, note that both my library of code and ATLAS are primarily interested
> in floating point computation performance. Different conclusions may be
> reached for other types of computation load though I very much doubt it.

Maybe you can that bring this up with gcc developers, suggesting they enable
-fPIC by default on x64?

- Volodya