In /usr/bin/mkdep line 74:
um=`umask`
   ^-----^ SC2006: Use $(...) notation instead of legacy backticked `...`.

Did you mean: 
um=$(umask)


In /usr/bin/mkdep line 81:
umask $um
      ^-^ SC2086: Double quote to prevent globbing and word splitting.

Did you mean: 
umask "$um"


In /usr/bin/mkdep line 82:
trap 'rm -rf $DTMP ; trap 2 ; kill -2 $$' 1 2 3 13 15
                                                ^-- SC2172: Trapping signals by number is not well defined. Prefer signal names.


In /usr/bin/mkdep line 90:
if [ $? != 0 ]; then
     ^-- SC2181: Check exit code directly with e.g. 'if mycmd;', not indirectly with $?.


In /usr/bin/mkdep line 97:
	cat $TMP >> $D
                    ^-- SC2086: Double quote to prevent globbing and word splitting.

Did you mean: 
	cat $TMP >> "$D"


In /usr/bin/mkdep line 98:
	if [ $? != 0 ]; then
             ^-- SC2181: Check exit code directly with e.g. 'if mycmd;', not indirectly with $?.


In /usr/bin/mkdep line 104:
	mv $TMP $D
                ^-- SC2086: Double quote to prevent globbing and word splitting.

Did you mean: 
	mv $TMP "$D"


In /usr/bin/mkdep line 105:
	if [ $? != 0 ]; then
             ^-- SC2181: Check exit code directly with e.g. 'if mycmd;', not indirectly with $?.

For more information:
  https://www.shellcheck.net/wiki/SC2172 -- Trapping signals by number is not...
  https://www.shellcheck.net/wiki/SC2086 -- Double quote to prevent globbing ...
  https://www.shellcheck.net/wiki/SC2006 -- Use $(...) notation instead of le...