Re: [lmi] Compiling takes longer with gcc-4.9.2

[Greg Chicares]

On 2016-01-05 13:33, Vadim Zeitlin wrote:
> On Tue, 05 Jan 2016 03:19:45 +0000 Greg Chicares <address@hidden> wrote:
[...]
> GC> Your table above actually lists two different versions of MinGW-w64
> GC> (last digit '1' or '2').
> 
>  This is because Cygwin version is 4.9.2 while Debian version is 4.9.1 and
> I wanted to ensure that the binaries created by the native compiler used
> inside the VM and Debian cross-compiler were compatible because I thought
> to use the libraries created by the former with the binaries generated by
> the latter at some moment. But then I decided it was a bad idea and that if
> we want to cross-compile, we should cross-compile everything instead of
> relying on doing part of the work inside the VM and part of it outside it.

Agreed. I'd like to stop using any msw VM at all, unless only for testing.

>  Also, 4.9.1 and 4.9.2 have the same ABI, so it shouldn't matter which one
> is used in any case. And I don't think (although I didn't measure it,
> should I?) there is any difference in build times between them neither

I doubt there's any difference in build times. I don't think that's worth
the trouble to investigate.

I believe we need to use the same MinGW-w64 toolchain version everywhere.
It's not enough to have the same ABI: we need the same compiler version,
the same binutils, and the same runtime library. Otherwise, our binaries
might easily differ. They "shouldn't", but some day they will. A "minor"
change in the runtime library can have unforeseen consequences; it has
happened with mingw.org's toolchain.