Bug#971018: libgnatcoll-db: FTBFS on mips(64)el with assembler message: branch out of range

Source: libgnatcoll-db
Version: 20.0-1
Severity: serious
Justification: fails to build from scratch on previously built architectures

Hello.

libgnatcoll-db/20.0-1 in experimental fails to build on
mipsel and mips64el with the following messages [1].
  /tmp/ccl8IVnY.s: Assembler messages:
  /tmp/ccl8IVnY.s:692755: Error: branch out of range
  /tmp/ccl8IVnY.s:693545: Error: branch out of range
  /tmp/ccl8IVnY.s:693669: Error: branch out of range

The problem seems related to a previous bug [2] with similar symptoms [3].
  xref/gnatcoll-xref.adb: In function ‘GNATCOLL.XREF’:
  xref/gnatcoll-xref.adb:40:1: note: variable tracking size limit exceeded with ‘-fvar-tracking-assignments’, retrying without
  Assembler messages:
  678119: Error: branch out of range

CFLAGS+=-mxgot has fixed the issue then, but does not seem sufficient
anymore.

Any advice would be welcome.

[1] https://buildd.debian.org/status/package.php?p=libgnatcoll-db&suite=experimental
[2] https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=953069
[3] https://buildd.debian.org/status/fetch.php?pkg=libgnatcoll-db&arch=mipsel&ver=19.2-2&stamp=1584014543&raw=0