Re: aarch64: use gcc8 as ports-gcc

On Thu, 31 Jan 2019 17:25:06 +0000, Stuart Henderson wrote:
> On 2019/01/31 11:28, Peter Hessler wrote:
> > On 2019 Jan 04 (Fri) at 17:57:54 +0100 (+0100), Pascal Stumpf wrote:
> > :This switches aarch64 to use GCC 8.2.0 as default. Doesn't do any harm
> > :because this is the first GCC port that works there.
> > :
> > :We still need to decide whether to hook up gcc8 on all archs or aarch64
> > :only ...
> > :
> >
> > Hook up gcc8 on all arches, it doesn't make sense not to.
>
> OK provided that there is no problem building any of the hooked up
> versions with 4.9 installed (and vice-versa).

You can build GCC 8 with 4.9 installed, and you can build GCC 4.9 with
GCC 8 installed.

However: On an arch that uses GCC 4.9 as default, you *cannot* build any
port that depends on GCC 4.9 if you have GCC 8 installed (the gcc-libs
package, to be precise). This is not a problem in bulk builds because
GCC 8 will never be installed in that situation.

Most importantly, ports *cannot* depend on GCC 8 on a GCC 4.9 arch.

> > :
> > :Index: gcc4.port.mk
> > :===================================================================
> > :RCS file: /cvs/ports/infrastructure/mk/gcc4.port.mk,v
> > :retrieving revision 1.12
> > :diff -u -p -r1.12 gcc4.port.mk
> > :--- gcc4.port.mk 8 Mar 2016 16:46:05 -0000 1.12
> > :+++ gcc4.port.mk 4 Jan 2019 16:02:48 -0000
> > :@@ -1,2 +1,6 @@
> > :+.if ${MACHINE_ARCH} == "aarch64"
> > :+MODGCC4_VERSION?=8
> > :+.else
> > : MODGCC4_VERSION?=4.9
> > :+.endif
> > : .include "${PORTSDIR}/lang/gcc/${MODGCC4_VERSION}/gcc4.port.mk"
> > :
> >
> > I have this applied locally on my bulk builds for the last 3-4 builds.
> >
> > OK
> >
> >
> > --
> > Finagle's Creed:
> > Science is true. Don't be misled by facts.
> >
>
> I think we should just switch all arches. There may be some new failures,
> but these arches aren't in great shape anyway and equally it's likely
> to fix some things (we currently have problems on gcc arches with ports
> depending on ICU due to the mixture of default C++ standards which
> I am expecting to be helped by this move as gcc 6.1+ uses c++14 by
> default).
>
> Switching all arches will however require bumps for ports using gcc.
>