-Wunsuffixed-float-constants triggers warning in gnulib's timespec.h
-Wunterminated-string-initialization enabled by -Wextra
-Wunused enabled by -Wall
--Wunused-but-set-parameter enabled by -Wunused
+-Wunused-but-set-parameter enabled by -Wextra -Wunused
-Wunused-but-set-variable enabled by -Wunused
-Wunused-const-variable covered by -Wunused-const-variable=2
-Wunused-const-variable=<0,2> gcc --help=warnings artifact
-Wunused-function enabled by -Wunused
-Wunused-label enabled by -Wunused
-Wunused-local-typedefs enabled by -Wunused
--Wunused-parameter enabled by -Wunused
+-Wunused-parameter enabled by -Wextra -Wunused
-Wunused-result enabled by -Wunused
-Wunused-value enabled by -Wunused
-Wunused-variable enabled by -Wunused