brew doctor - How to fix these warnings and what do they mean

Question

When I run brew doctor on my Mac, I get the following warnings:

Warning: Unbrewed dylibs were found in /usr/local/lib.
If you didn't put them there on purpose they could cause problems when
building Homebrew formulae, and may need to be deleted.

Unexpected dylibs:
    /usr/local/lib/libntfs-3g.80.dylib
    /usr/local/lib/libntfs.9.0.0.dylib
    /usr/local/lib/libublio.1.dylib

Warning: Unbrewed .la files were found in /usr/local/lib.
If you didn't put them there on purpose they could cause problems when
building Homebrew formulae, and may need to be deleted.

Unexpected .la files:
    /usr/local/lib/libntfs-3g.la
    /usr/local/lib/libntfs.la
    /usr/local/lib/libublio.la

Warning: Unbrewed .pc files were found in /usr/local/lib/pkgconfig.
If you didn't put them there on purpose they could cause problems when
building Homebrew formulae, and may need to be deleted.

Unexpected .pc files:
    /usr/local/lib/pkgconfig/fuse.pc
    /usr/local/lib/pkgconfig/libntfs-3g.pc
    /usr/local/lib/pkgconfig/libublio.pc

Warning: Unbrewed static libraries were found in /usr/local/lib.
If you didn't put them there on purpose they could cause problems when
building Homebrew formulae, and may need to be deleted.

Unexpected static libraries:
    /usr/local/lib/libntfs-3g.a
    /usr/local/lib/libntfs.a
    /usr/local/lib/libublio.a

Warning: You have uncommitted modifications to Homebrew
If this a surprise to you, then you should stash these modifications.
Stashing returns Homebrew to a pristine state but can be undone
should you later need to do so for some reason.
    cd /usr/local/Library && git stash && git clean -d -f

I can make out from the above 3 warnings that some of them are related to NTFS-3g and libfuse that I installed without using Homebrew, but other than that I don't know how to fix them.

Should I be worried about these warnings? Also, the last warning about changes made to Homebrew installation also worries me, because I haven't made any changes.

How should I fix these warnings?

Answer 1

First of all, these are warnings only, so if nothing is broken it might be prudent to do nothing.

If you don't need ntfs-3g and fuse anymore, just delete those files. You could also consider re-installing these using brew afterwards.

To check what was modified in your Homebrew checkout, do

cd /usr/local/Library
git diff