This bug was fixed in the package squid - 4.6-2ubuntu4
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squid (4.6-2ubuntu4) eoan; urgency=medium
* Fix gcc-9 issues (LP: #1835831)
- Remove -Wno-sizeof-pointer-memaccess -Wno-stringop-truncation
- debian/patches/more-gcc-9-fixes.patch: switch to xstrncpy in
I uploaded a workaround, and the gcc-9 upstream patch
http://launchpadlibrarian.net/433155919/squid_4.6-2ubuntu1_4.6-2ubuntu3.diff.gz
and an export of
"-Wno-sizeof-pointer-memaccess -Wno-stringop-truncation"
flags.
It shouldn't make things worse, because the bugs are already there, but at
least
