warnings with -Wextra

[xosevp]

Relevant ones (???):

ifconfig.c:742:37: warning: comparison of unsigned expression in ‘< 0’ is always false [-Wtype-limits]
ifconfig.c:833:37: warning: comparison of unsigned expression in ‘< 0’ is always false [-Wtype-limits]
ifconfig.c:924:33: warning: comparison of unsigned expression in ‘< 0’ is always false [-Wtype-limits]

ash.c:42:19: warning: comparison is always true due to limited range of data type [-Wtype-limits]
ash.c:42:37: warning: comparison is always true due to limited range of data type [-Wtype-limits]

netstat.c:473:47: warning: ‘%s’ directive output may be truncated writing up to 255 bytes into a region of size 20 [-Wformat-truncation=] (in TODO)

netstat.c:406:5: warning: ‘security_context_t’ is deprecated [-Wdeprecated-declarations] (in TODO)

Then there are many of:
"'X' may be used uninitialized"
"this statement may fall through"
"suggest braces around empty body in an ‘if’ statement"
"missing initializer for field ‘X’ of ‘Y‘"
"comparison of integer expressions of different signedness: ‘X’ and ‘Y‘"
"unused parameter 'X'"

[ecki]

I guess there is a reason why its not set by default .)

If somebody wants to provide a patch, maybe group them by obvious/trivial/critical problems to speed up review.

[xosevp]

The chicken or the egg problem.
Nobody sees it, nobody fixes it.

Enabling it is harmless, so:
Wextra.diff.txt