[flac-dev] FLAC__SSE_OS change

[lvqcl]

yErik de Castro Lopo wrote:

> I think I've fixed both those in:
>
>     commit 23778a3a6018f5dcb5fc1ad6ac97ad8391afc69d
>     Author: Erik de Castro Lopo <erikd at mega-nerd.com>
>     Date:   Sat Jun 25 17:02:06 2016 +1000
>
>         libFLAC/cpu.c: More pre-processor cleanups
>
>
> I've tested on this in x86, x86_64, powerpc and armhf linux as well as
> cross-compiling from linux to x86 and x86_64 Windows.


So if I understand things correctly, the current meaning of --(en|dis)able-sse is:

on Linux:
     --enable-sse:
         add -msse2 to the compiler switches
         do not test SSE OS support (assume that SSE is supported)
     --disable-sse:
         do NOT add -msse2
         test SSE OS support

on other OSes:
     --enable-sse:
         add -msse2 to the compiler switches
         test SSE OS support  (why?)
     --disable-sse:
         do NOT add -msse2
         test SSE OS support

It's a bit contradictory: why test whether *BSD etc support SSE or not
but at the same time allow compiler to use SSE/SSE2 unconditionally?


Also: are there any compilers / target OSes such that libFLAC currently
has no way to test OS support of SSE? The current code will always
disable SSE for such builds:
     --enable-sse:
         add -msse2 to the compiler switches
         disable the use of SSE code
     --disable-sse:
         do NOT add -msse2
         disable the use of SSE code

previously --enable-sse made it possible to override this.


> Please test compiling on Windows and anything else you can get your
> hands on.

Will do.
MSVC 2015: builds OK.