[Libreoffice] unnecessary build actions?

Hullo LibO Devs,

In a search of my build.log for libuno_sal, the first reference I see 
points me to lines that look line this (newlines added for email clarity):

-----
rm -f ../unxlngx6/lib/check_libuno_sal.so.3

mv ../unxlngx6/lib/libuno_sal.so.3 ../unxlngx6/lib/check_libuno_sal.so.3

[...]/solenv/bin/checkdll.sh  [...]  ../unxlngx6/lib/check_libuno_sal.so.3

rm -f ../unxlngx6/lib/libuno_sal.so

cd ../unxlngx6/lib && ln -s libuno_sal.so.3 libuno_sal.so

Making:    libuno_sal.so.3

ccache g++ [...] -o ../unxlngx6/lib/libuno_sal.so.3 [...]
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Question: if we're making libuno_sal.so.3 afresh, what's the rational to 
bother performing various checks on it prior to making it?

Further, I don't see where the first line's reference to 
check_libuno_sal.so.3 comes from.  i.e.  When did it get built prior? 
Similar question goes for line 2 above (mv ...).

In a very similar vein, I see lots of this paradigm:

...
rm -f path/to/file
gcc -o path/to/file [...]
...

That gcc command will just overwrite the file if it's there, no? 
Therefore, why execute rm?

Thanks,

Kevin