Building cmake DEBUG version errors on null destination pointer for STRstring2Array

This is not very important for me since I can build the RELEASE version just fine but I figured I'd report it anyway.

If I try to build the DEBUG release with cmake (commit bed278c6 but I've had it before I think), then I get the following error:

[ 48%] Building C object src/libsac2c/CMakeFiles/sac2cShared.dir/support/str.c.o
In file included from /nix/store/m3n0h7646c7qwf6dbvdqhslmxmv2dg3z-glibc-2.40-66-dev/include/stdio.h:970,
                 from /home/uni/code/uni/sac2c/src/libsac2c/types/types.h:10,
                 from /home/uni/code/uni/sac2c/src/libsac2c/support/str.h:4,
                 from /home/uni/code/uni/sac2c/src/libsac2c/support/str.c:10:
In function ‘sprintf’,
    inlined from ‘STRstring2Array’ at /home/uni/code/uni/sac2c/src/libsac2c/support/str.c:1317:9:
/nix/store/m3n0h7646c7qwf6dbvdqhslmxmv2dg3z-glibc-2.40-66-dev/include/bits/stdio2.h:30:10: error: null destination pointer [-Werror=format-overflow=]
   30 |   return __builtin___sprintf_chk (__s, __USE_FORTIFY_LEVEL - 1,
      |          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   31 |                                   __glibc_objsize (__s), __fmt,
      |                                   ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   32 |                                   __va_arg_pack ());
      |                                   ~~~~~~~~~~~~~~~~~
compilation terminated due to -Wfatal-errors.
cc1: all warnings being treated as errors
make[2]: *** [src/libsac2c/CMakeFiles/sac2cShared.dir/build.make:5839: src/libsac2c/CMakeFiles/sac2cShared.dir/support/str.c.o] Error 1
make[1]: *** [CMakeFiles/Makefile2:1214: src/libsac2c/CMakeFiles/sac2cShared.dir/all] Error 2
make: *** [Makefile:166: all] Error 2