[tlbuild] tl17 trial builds

[Ken Moffat]

On Tue, Mar 21, 2017 at 11:15:27PM +0000, Karl Berry wrote:
>     only available with -std=c++11
> 
> Ok, that's expected. We'd have to change our configure to insert that
> flag, as the original poppler configure did.
> 
> But since Akira has reverted poppler to the previous version in the
> meantime, I guess we will go that route for this release. So you can go
> back to Debian 6 if you want.
> 
>     configure: error: *** A compiler with support for C++11 language features is required.
> 
> It is sad that even the compiler on Debian 7 is not good enough for
> dvisvgm. The configure macro doesn't just check for the presence/absence
> of the flag, but checks a lot of actual language features:
>   https://www.gnu.org/software/autoconf-archive/ax_cxx_compile_stdcxx.html
> 
> Next year there may be no choice but to require C++11, if this trend
> continues ... -k

When you guys get to asymptote (if you haven't already forced it
back to an older version), with 2.40 in my own builds I've been
using '-O2' among my own CFLAGS/CXXFLAGS and that overrides the
default (CXXFLAGS, I presume) of

 -std=c++11 -g -O3 -fno-var-tracking

so maybe that would help on older compilers.  I do recall that
John Bowman considered that to be 'unoptimised' and was very much
against it, so perhaps it isn't a suitable workaround. (It was a
workaround for gcc-6.3.0 requiring -std=c++11 when -O3 was used in
2.39).

ĸen
-- 
`I shall take my mountains', said Lu-Tze. `The climate will be good
for them.'     -- Small Gods