Re: [dpdk-dev] [PATCH] mk: Rework gcc version detection to permit versions newer than 4.x

[Panu Matilainen <pmatilai@redhat.com>]

On 02/20/2015 04:04 PM, Thomas Monjalon wrote:
> Hi Panu,
>
> 2015-02-18 14:11, Panu Matilainen:
>> Separately comparing major and minor versions becomes seriously clumsy
>> when with major version changes, convert the entire version string into
>> a numeric value (ie 4.6.0 becomes 460 and 5.0.0 becomes 500) and use
>> that for comparisons. This simplifies the comparisons and makes
>> gcc 5.0 naturally recognized at least as capable as newest 4.x.
>>
>> This three-digit scheme would run into trouble if gcc ever went to
>> two-digit version segments, but that hasn't happened in the last 10+
>> years so it seems like a safe assumption.
>>
>> Signed-off-by: Panu Matilainen <pmatilai@redhat.com>
>
> Yes this version checking was totally buggy.
> Thanks for improving it.
>
> I have a comment about the conversion of old versions checks.
>
>> -ifneq ($(shell test $(GCC_MAJOR_VERSION) -le 4 -a $(GCC_MINOR_VERSION) -le 3 && echo 1), 1)
>> +ifneq ($(shell test $(GCC_VERSION) -le 430 && echo 1), 1)
>
> The previous check was a buggy "if not <= 4.3.x"
> Your check is "if not <= 4.3.0"
> So it's a bit different.

Ah, indeed. Thanks for pointing that out.

> And I think we should remove negation to make it simpler:
> 	"if >= 4.4.0"
>
> I have the same comment for other changes in the patch.

Ok, since the change seems welcome I'll fix/simplify the above cases and 
send a new version.

	- Panu -