port-macppc/54827: alloca() is broken in gcc 8 on powerpc

[uwe%stderr.spb.ru@localhost]

>Number:         54827
>Category:       port-macppc
>Synopsis:       alloca() is broken in gcc 8 on powerpc
>Confidential:   no
>Severity:       serious
>Priority:       high
>Responsible:    port-macppc-maintainer
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Thu Jan 02 21:45:00 +0000 2020
>Originator:     Valery Ushakov
>Release:        NetBSD 9.99.32
>Organization:
>Environment:
NetBSD snips.stderr.spb.ru 9.99.32 NetBSD 9.99.32 (GENERIC) #2: Thu Jan  2 06:50:25 MSK 2020  uwe@majava:/home/uwe/work/netbsd/cvs/src/sys/arch/macppc/compile/GENERIC macppc

>Description:
powerpc ports were switched to gcc-8 on 2019-12-14.  In a system built
after that date cc1 gets a segmentation fault and gdb cannot start.

$ cc --version | sed 1q
cc (nb1 20190930) 8.3.0
$ > empty.c
$ /usr/libexec/cc1 empty.c
<built-in>: internal compiler error: Segmentation fault
...
$


$ gdb
Undefined save command: "tracepoints".  Try "help save".
$ 

Full details and initial analysis in a follow-up mail as the margins
of this html form are too narrow...

>How-To-Repeat:

>Fix: