[tlbuild] Compiling asy with recent gcc

[Ken Brown]

On 3/5/2020 6:53 PM, Nelson H. F. Beebe wrote:
> Ken Brown <kbrow1i at gmail.com> reports a failure in building Asymptote
> on Cygwin with gcc-9.2.0 (newly upgraded from gcc-7.4.x):
> 
>>> When I build asy with this compiler it crashes in the sort2 test.
>>> Running the test under gdb shows that there's a null pointer
>>> dereference in GC_free (hhdr is null). If I build without
>>> optimization, the problem doesn't occur.
> 
> I just scanned all of the asy executables available at
> 
>      http://www.math.utah.edu/pub/texlive-utah/bin
> 
> and found that TeX Live 2020 for these files were built with a gcc-9.x
>>> compiler:
> 
>      amd64-clonos19/asy              GCC: (FreeBSD Ports Collection) 9.2.0
>      amd64-freebsd130/asy            GCC: (FreeBSD Ports Collection) 9.2.0
>      amd64-hardenedbsd13/asy         GCC: (FreeBSD Ports Collection) 9.1.0
>      x86_64-arco19/asy               GCC: (GNU) 9.2.0
>      x86_64-blackarch/asy            GCC: (GNU) 9.2.0
>      x86_64-budgie1910/asy           GCC: (Ubuntu 9.2.1-9ubuntu2) 9.2.1 20191008
>      x86_64-centos8/asy              GCC: (GNU) 9.1.1 20190605 (Red Hat 9.1.1-2)
>      x86_64-fedora30/asy             GCC: (GNU) 9.2.1 20190827 (Red Hat 9.2.1-1)
>      x86_64-fedora31/asy             GCC: (GNU) 9.2.1 20190827 (Red Hat 9.2.1-1)
>      x86_64-kali-2/asy               GCC: (Debian 9.2.1-25) 9.2.1 20200123
>      x86_64-kaos2020/asy             GCC: (GNU) 9.2.0
>      x86_64-manjaro19/asy            GCC: (GNU) 9.2.1 20200130 GCC: (Arch Linux 9.2.1+20200130-2) 9.2.1 20200130
>      x86_64-openmandriva41-clang/asy GCC: (GNU) 9.2.1 20191109 (OpenMandriva) GCC: (GNU) 9.2.1 20191207 (OpenMandriva)
>      x86_64-openmandriva41/asy       GCC: (GNU) 9.2.1 20191109 (OpenMandriva) GCC: (GNU) 9.2.1 20191207 (OpenMandriva)
>      x86_64-opensusetw2/asy          GCC: (SUSE Linux) 9.2.1 20190903 [gcc-9-branch revision 275330]
>      x86_64-oracle8/asy              GCC: (GNU) 9.1.1 20190605 (Red Hat 9.1.1-2)
>      x86_64-slackware15/asy          GCC: (GNU) 9.2.0
>      x86_64-trident-void-linux/asy   GCC: (GNU) 9.1.0 GCC: (GNU) 9.2.0
>      x86_64-ubuntu1910/asy           GCC: (Ubuntu 9.2.1-9ubuntu2) 9.2.1 20191008
>      x86_64-ubuntu2004/asy           GCC: (Ubuntu 9.2.1-21ubuntu1) 9.2.1 20191130
> 
> With rare exceptions, I do not supply optimization levels when I build
> TeX Live snapshots, and I don't install a build at the above URL if
> there are segmentation faults in the build.
> 
> Thus, I'm surprised by Ken's report, and it looks like something that
> we need to figure out what is happening.
> 
> Ken's report didn't mention the Asymptote version. As of yesterday's
> source tree update, it is 2.64.  Almost all of my builds, except for
> the NetBSD systems, have been with Asymptote version 2.62 or 2.63.
> 
> ----------------------------------------
> 
> P.S. I note that gcc-8.4.0 was officially released yesterday, and many
> O/S distributions allow installation of multiple major versions of gcc
> and clang, without name conflicts.  I typically install all of them on
> our test lab machiens, and I've done thousands of builds of gcc and
> scores of clang, from source code on our systems.  Thus, that
> compiler, if available on Cygwin, would be an alternative.  It is
> already in the Ubuntu 20.04 package system, as I found when I updated
> one of our 20.04 systems this morning.  Its announcement claimed
> over 200 bug fixes compared to gcc-8.3.0.

Thanks, Nelson, and thanks to everyone else who replied.  It seems that this 
issue is specific to the Cygwin build of gcc-9.2.0.