Bug#925823: scotch: ftbfs with GCC-9

[Drew Parsons]

Package: scotch
Version: 6.0.7-2
Followup-For: Bug #925823

gdb backtrace suggests the error occurs in l.229 order_io.c:

Program received signal SIGSEGV, Segmentation fault.
0x00007ffff7f9c2f9 in _SCOTCHorderSaveMap (ordeptr=<optimized out>,
vlbltab=<optimized out>, stream=0x555555559260) at order_io.c:229
229order_io.c: No such file or directory.
(gdb) bt
#0  0x00007ffff7f9c2f9 in _SCOTCHorderSaveMap (ordeptr=<optimized
out>, vlbltab=<optimized out>, stream=0x555555559260) at order_io.c:229
#1  0x00005555555553e5 in main (argc=<optimized out>, argv=<optimized
out>) at test_scotch_graph_order.c:143


order_io.c:229 says...
   if (fprintf (stream, GNUMSTRING "\t" GNUMSTRING "\n",   
from ...
  vlbltax = (vlbltab != NULL) ? (vlbltab - ordeptr->baseval) : NULL;
  for (vnodnum = ordeptr->baseval, o = 0; vnodnum < vnodnnd; vnodnum ++) {
    if (fprintf (stream, GNUMSTRING "\t" GNUMSTRING "\n",
                 (Gnum) ((vlbltax != NULL) ? vlbltax[vnodnum] : vnodnum),
                 (Gnum) cblktax[vnodnum]) == EOF) {
      errorPrint ("orderSaveMap: bad output (2)");
      o = 1;
      break;
    }
  }

stream is not zero...
(gdb) p stream
$1 = (FILE * const) 0x555555559260

vlbltax is zero...
(gdb) p vlbltax
$5 = (const Gnum * restrict) 0x0

but that is supposed to be guarded in the call with vlbltax != NULL.

Does it mean the use of the "vlbltax != NULL" pattern is now broken in
gcc9 ?


-- System Information:
Debian Release: bullseye/sid
  APT prefers unstable
  APT policy: (500, 'unstable'), (1, 'experimental')
Architecture: amd64 (x86_64)
Foreign Architectures: i386

Kernel: Linux 4.19.0-5-amd64 (SMP w/4 CPU cores)
Kernel taint flags: TAINT_WARN, TAINT_OOT_MODULE, TAINT_UNSIGNED_MODULE
Locale: LANG=en_AU.UTF-8, LC_CTYPE=en_AU.UTF-8 (charmap=UTF-8), LANGUAGE=en_AU.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)
LSM: AppArmor: enabled

Versions of packages scotch depends on:
ii  libbz2-1.0     1.0.6-9.2
ii  libc6          2.28-10
ii  liblzma5       5.2.4-1
ii  libopenmpi3    3.1.3-11
ii  libscotch-6.0  6.0.7-2
ii  zlib1g         1:1.2.11.dfsg-1+b1

scotch recommends no packages.

scotch suggests no packages.

-- no debconf information