compile warinig message [wimplicit-fallthrough]

[chaeya]

put below option in *.pro file
QMAKE_CXXFLAGS += -Wimplicit-fallthrough=0

ref :
https://developers.redhat.com/blog/2017/03/10/wimplicit-fallthrough-in-gcc-7/

-Wimplicit-fallthrough=0 disables the warning altogether.
-Wimplicit-fallthrough=1 treats any kind of comment as a “falls through” comment.
-Wimplicit-fallthrough=2 essentially accepts any comment that contains something that matches (case insensitively) “falls?[ \t-]*thr(ough|u)” regular expression.
-Wimplicit-fallthrough=3 case sensitively matches a wide range of regular expressions, listed in the GCC manual.