[FFmpeg-cvslog] r20497 - trunk/configure

[Måns Rullgård]

Reimar D?ffinger <Reimar.Doeffinger at gmx.de> writes:

> On Sun, Nov 15, 2009 at 01:58:12AM -0500, Alexander Strange wrote:
>> 
>> On Nov 14, 2009, at 10:38 PM, M?ns Rullg?rd wrote:
>> 
>> > Alexander Strange <astrange at ithinksw.com> writes:
>> > 
>> >> On Nov 10, 2009, at 7:57 AM, reimar wrote:
>> >> 
>> >>> Author: reimar
>> >>> Date: Tue Nov 10 13:57:28 2009
>> >>> New Revision: 20497
>> >>> 
>> >>> Log:
>> >>> Check if PIC is somehow already enabled (e.g. a compiler that enables it by default).
>> >>> This in particular ensures that -DPIC is set appropriately for YASM, which avoids
>> >>> linking failures on x86_64 for compilers that have PIE enabled by default
>> >>> (e.g. hardened Gentoo).
>> >>> It also makes the macho64 special-case hack adding -DPIC to YASMFLAGS obsolete.
>> >> 
>> >> This broke adding -mdynamic-no-pic on Darwin again.
>> > 
>> > Can you please explain what the problem is?
>> 
>> The compiler defaults to PIC, so that check runs 'enable pic'.
>> 
>> After that, -mdynamic-no-pic, which turns it off again, is under ! 'enabled_any pic shared', so it's not added.
>
> Hm. It was specifically for that check I put this before it, however I
> misread the condition.

What does that flag do anyway?

>> Maybe it shouldn't be using the same variable for PIC being
>> detected and the user specifically requesting it, but that won't
>> fix this check, which either needs to not run for Darwin or to run
>> after the flag is added.
>
> Why is adding that flag conditional on PIC anyway?

IIRC it was supposed to do something allowing non-pic code in shared
libs.  Now that doesn't make much sense if, as you say, PIC is always
on with that compiler.

So which way is it?

-- 
M?ns Rullg?rd
mans at mansr.com