Gentoo's Bugzilla –
Attachment 854282 Details for
Bug 896200mate-extra/mate-sensors-applet-1.26.0 fails to compile (MUSL-CLANG-SYSTEM): i2c-proc-plugin.c:148:31: error: call to undeclared function setlocale; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]