Re: [master][dora][PATCH 1/2] perf: disallow debug optimization.

[Mark Hatle <mark.hatle@windriver.com>]

On 11/21/13, 8:25 AM, Phil Blundell wrote:
> On Thu, 2013-11-21 at 01:33 -0600, Mark Hatle wrote:
>> +def get_optimization(d):
>> +    selected_optimization = d.getVar("SELECTED_OPTIMIZATION", True)
>> +    if base_contains("SELECTED_OPTIMIZATION", "-O0", "x", "", d) == "x":
>> +        bb.note("eglibc can't be built with -O0, -O2 will be used instead.")
>
> Although the text of that warning is correct, users might find the
> reference to eglibc slightly confusing if it's perf that they're trying
> to build.

I'll get that fixed.

> Also, as I mentioned in a different thread not all that long ago when
> someone submitted a similar patch for gcc-runtime, the proliferation of
> parse-time python functions to bash SELECTED_OPTIMIZATION around doesn't
> seem like all that good a thing: this will cause extra overhead for
> everyone, even those who are not using -O0 and have no interest in perf.

We have users who desire to build their system at different levels of 
optimizations for debug, size, profiling, etc.  So they do change the default 
optimization levels from -O2 to -O0, etc.  The python fragement is used to only 
adjust -O0, as -O1 (or -Os) work correctly.

--Mark

> And, finally, it remains slightly unclear to me that this is really a
> problem that the metadata needs to be solving.  I haven't seen any
> particularly convincing explanation of why this can't or shouldn't just
> be fixed in the distro configuration.
>
> p.
>
>