cc -O2 -pipe  -pthread  -Wall -Wextra -Werror -Wno-error=deprecated -Wno-error=deprecated-declarations signal/mcontext_t.c -o signal/mcontext_t -D_POSIX_C_SOURCE=202405L  -lm -lpthread 
signal/mcontext_t.c:2:1: error: unknown type name 'mcontext_t'; did you mean 'ucontext_t'?
mcontext_t* foo;
^~~~~~~~~~
ucontext_t
/usr/include/sys/signal.h:190:27: note: 'ucontext_t' declared here
typedef struct sigcontext ucontext_t;
                          ^
1 error generated.