Each double library function may have up to nine other companions for float, long double, long long double, extended (synonym __float80), quad (synonym __float128), decimal float, decimal double, decimal long double, and decimal long long double variants. However, only one of these variants is included in the list below. Most systems will have only the float, double, and long double variants, since the others require compiler extensions.
While the prefix /usr/local is widely used at the directory tree in which local software installations are done, and is the GNU Project standard, some sites choose other locations, so the sample compiler lines in the manual pages may need (mental) adjustment for your site.