This package currently fails to build (at least on the amd64
architecture) with link time optimizations enabled.  For a background
for LTO please see

https://wiki.debian.org/ToolChain/LTO

The goal is to enable this optimization by default in an upcoming
Debian release in dpkg-buildflags for 64bit architectures.  The goal
is to get this package to build with link time optimizations, or to
explicitly disable link time optimizations for this package build.

To reproduce the build failure, enable the lto optimization in
testing/unstable by adding "optimize=+lto" to DEB_BUILD_MAINT_OPTIONS
in the debian/rules file, or if this macro is unset, just set it:

export DEB_BUILD_MAINT_OPTIONS = optimize=+lto

Please try to fix the build with lto enabled, fixing the packaging or
forwarding the issue upstream. If the issue cannot be fixed,
explicitly disallow building the package with lto by adding to your
rules file:

export DEB_BUILD_MAINT_OPTIONS = optimize=-lto

or adding that string to your existing setting of DEB_BUILD_MAINT_OPTIONS.

The full build log can be found at:
http://qa-logs.debian.net/2022/06/09/dpkglto/fricas_1.3.7-5_unstable_dpkglto.log
The last lines of the build log are at the end of this report.

[...]
T

COMPILER>
NIL

COMPILER>4296091136 heap words available
NIL

COMPILER>;; Loading "/usr/lib/gcl-2.6.12/unixport/../cmpnew/gcl_collectfn.lsp"
;; Finished loading "/usr/lib/gcl-2.6.12/unixport/../cmpnew/gcl_collectfn.lsp"
NIL

COMPILER>
"prelisp"
Dedicated to the memory of W. Schelter

Use (help) to get some basic information on how to use GCL.
Temporary directory for compiler files:
/tmp/
;; Finished loading "fricas-package.lisp"
T
;; Finished loading "fricas-config.lisp"
T
Error:
Fast links are on: do (si::use-fast-links nil) for debugging
Signalled by LOAD.
Condition in LOAD [or a callee]: INTERNAL-SIMPLE-ERROR: The assertion !emsg("Unrelocated non-local symbol: %s\n",st1+sym->st_name) on line 238 of sfaslelf.c in function relocate_symbols failed: Success

Broken at LOAD.  Type :H for Help.
    1  Return to top level.
start address -T 0xf1d330 ;; Finished loading "primitives.o"
71088

Condition in LOAD [or a callee]: INTERNAL-SIMPLE-UNDEFINED-FUNCTION: Cell error on SAVE-CORE: Undefined function:

Broken at LOAD.
    1 (abort) Return to debug level 1.
    2  Return to top level.
FRICAS-LISP>>>make[3]: *** [Makefile:251: do_it.gcl] Error 255
make[3]: Leaving directory '/<<PKGBUILDDIR>>/src/lisp'
make[2]: *** [Makefile:229: all-lisp] Error 2
make[2]: Leaving directory '/<<PKGBUILDDIR>>/src'
make[1]: *** [Makefile:251: all-src] Error 2
make[1]: Leaving directory '/<<PKGBUILDDIR>>'
make: *** [debian/rules:43: build-stamp] Error 2
dpkg-buildpackage: error: debian/rules binary subprocess returned exit status 2