Failure to distribute distcc jobs compiling kernel versions >=5.2.0

[John]

Compiling the kernel using distcc since version 5.1.16 works but
versions >=5.2.0 fail to distribute jobs. This is true compiling
5.4-rc2.  Whatever is causing this breakage, it has not been
backported to the 4.19-lts series. I can build 4.19.78 with distcc
working just fine.

distcc v3.3.3
gcc v9.2.0

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Example compiling a recent kernel on the distcc client:
distcc[22629] (dcc_readx) ERROR: unexpected eof on fd5
distcc[22629] (dcc_r_token_int) ERROR: read failed while waiting for
token "DONE"
distcc[22629] (dcc_r_result_header) ERROR: server provided no answer.
Is the server configured to allow access from your IP address? Is the
server performing authentication and your client isn't? Does the
server have the compiler installed? Is the server configured to access
the compiler?
distcc[22629] Warning: failed to distribute
scripts/mod/devicetable-offsets.c to 10.1.1.102/5, running locally
instead
distcc[22635] (dcc_readx) ERROR: unexpected eof on fd5
distcc[22635] (dcc_r_token_int) ERROR: read failed while waiting for
token "DONE"
distcc[22635] (dcc_r_result_header) ERROR: server provided no answer.
Is the server configured to allow access from your IP address? Is the
server performing authentication and your client isn't? Does the
server have the compiler installed? Is the server configured to access
the compiler?
distcc[22635] Warning: failed to distribute scripts/mod/empty.c to
10.1.1.102/5, running locally instead