[coreboot] QEMU build failure in master

[Timothy Pearson]

On 05/06/2015 11:46 AM, Aaron Durbin wrote:
> On Wed, May 6, 2015 at 9:45 AM, Timothy Pearson
> <tpearson at raptorengineeringinc.com>  wrote:
>> On 05/06/2015 11:41 AM, Aaron Durbin wrote:
>>>
>>> That's probably my fault. I was under the impression monotonic_timer
>>> was a first class citizen now (I at least recall someone doing that) I
>>> thought wrong?
>>>
>>> You could add the following in the beginning of that function:
>>>
>>> if (!IS_ENABLED(CONFIG_HAVE_MONOTONIC_TIMER)
>>>      return 0;
>>>
>>> I need to look at your logs to know the build failure.
>>>
>>
>> While I don't have the entire log available right now, this was the
>> important part:
>> coreboot/src/lib/timestamp.c:184: undefined reference to
>> `timer_monotonic_get'
>>
>> There were no other errors, and no other warning output except from iasl (as
>> usual).
>>
>> It looks like timer_monotonic_get may not be available on QEMU, which means
>> your fix wouldn't work unless the entire block was #ifdefed out.
>
> The compiler would throw out that code not used using dead code elimination.

All right, I wasn't sure if we wanted to rely on that or not.  It 
"feels" fragile at first glance, and might provide an unpleasant 
surprise down the line to a programmer less familiar with the internal 
workings of compilers.

-- 
Timothy Pearson
Raptor Engineering
+1 (415) 727-8645
http://www.raptorengineeringinc.com