Ticket #1381: fuzzers: fix in fuzz_sub modifications
Contributes #1381 (closed)
Reproducer to check fuzzers building before and after modification:
$ mkdir -p build.san
$ cd build.san/
$ ../.check-in-docker.sh CC=clang CFLAGS=-fsanitize=fuzzer-no-link cmake -DENABLE_FUZZING=ON -DCMAKE_BUILD_TYPE=RelWithDebInfo -DWITH_ASAN=1 -DWITH_UBSAN=1 ..
$ ../.check-in-docker.sh make -j$(nproc) fuzzers