Windows breakage -- again

[Páli Gábor János]

2014-07-17 0:51 GMT+02:00 Páli Gábor János <pali.gabor at gmail.com>:
> 2014-07-17 0:47 GMT+02:00 Niklas Larsson <metaniklas at gmail.com>:
>> I hope they can just be done away with at the source, that is to make gcc
>> generate the assembly primitives. GHC should already be built with i686, but
>> does that reach ghc-prim?
>
> This depends on GCC -- if no -march=XXX is explicitly set, I guess it
> will take its default, which may vary platform by platform.

All right, I have finally got a Windows (x64) machine and installed
the msys2 environment by the GHC wiki [1].  This has GCC 4.5.2 (as
Niklas wrote earlier), where the default -march is i386.  You should
see this line when trying to compile Johan's test program with the -v
flag set:

COLLECT_GCC_OPTIONS= ... '-v' '-mtune=i386' '-march=i386'

With the -march=i586 flag explicitly set in the command line, no
__sync_fetch_and_add_n() calls are generated.

[1] https://ghc.haskell.org/trac/ghc/wiki/Building/Preparation/Windows/MSYS2