Internal error with gawk-5.3.0

[Sam James]

Machine Type: x86_64-pc-linux-gnu

Gawk Version: 5.3.0

Attestation 1:
        I have read 
https://www.gnu.org/software/gawk/manual/html_node/Bugs.html.
        Yes

Attestation 2:
        I have not modified the sources before building gawk.
        True / False
        True

Description:
        We received a downstream report in Gentoo of an internal error with
        gawk at https://bugs.gentoo.org/921503.

        gawk crashes with an 'internal error'.

        Backtrace:
        Program received signal SIGSEGV, Segmentation fault.
        0x000055555557b1eb in do_match (nargs=<optimized out>) at 
/usr/src/debug/sys-apps/gawk-5.3.0/gawk-5.3.0/builtin.c:2796
        2796                            rlength = wc_indices[rstart + rlength] 
- wc_indices[rstart];
        (gdb) bt
        #0  0x000055555557b1eb in do_match (nargs=<optimized out>) at 
/usr/src/debug/sys-apps/gawk-5.3.0/gawk-5.3.0/builtin.c:2796
        #1  0x000055555559e4b5 in r_interpret (code=<optimized out>) at 
/usr/src/debug/sys-apps/gawk-5.3.0/gawk-5.3.0/interpret.h:1089
        #2  0x000055555555aa51 in main (argc=<optimized out>, argv=<optimized 
out>) at /usr/src/debug/sys-apps/gawk-5.3.0/gawk-5.3.0/main.c:549
        (gdb)

Repeat-By:
        $ gawk -v b=1111-22-33 -v r="^([0-9]{4}(-[0-9]{2}(-[0-9]{2})?)?)?$" '
        END { match(b,"^([^,]*)(,(.*))?$",m)
              print m[1]

              print match(m[1],r)
              print match(m[3],r)
            } ' /dev/null
        1111-22-33
        1
        gawk: cmd. line:6: fatal error: internal error
        Aborted (core dumped)