while running make file in alpinelinux (musl-libc) i am getting the following errors pls help

../include_core/omrsig.h:104:82: error: expected initializer before '__THROW'
int sigaction(int signum, const struct sigaction *act, struct sigaction *oldact) __THROW;
^~~~~~~
../include_core/omrsig.h:105:55: error: expected initializer before '__THROW'
sighandler_t signal(int signum, sighandler_t handler) __THROW;
^~~~~~~
../include_core/omrsig.h:107:49: error: expected initializer before '__THROW'
sighandler_t sigset(int sig, sighandler_t disp) __THROW;
^~~~~~~
../include_core/omrsig.h:108:24: error: expected initializer before '__THROW'
int sigignore(int sig) __THROW;
^~~~~~~
../include_core/omrsig.h:109:59: error: expected initializer before '__THROW'
sighandler_t bsd_signal(int signum, sighandler_t handler) __THROW;
^~~~~~~
../include_core/omrsig.h:111:60: error: expected initializer before '__THROW'
sighandler_t sysv_signal(int signum, sighandler_t handler) __THROW;
^~~~~~~
../include_core/omrsig.h:119:68: error: expected initializer before '__THROW'
int sigvec(int sig, const struct sigvec *vec, struct sigvec *ovec) __THROW;
^~~~~~~
../include_core/omrsig.h:125:1: error: '__sighandler_t' does not name a type
__sighandler_t __sysv_signal(int sig, __sighandler_t handler) __THROW;
^~~~~~~~~~~~~~
../include_core/omrsig.h:126:53: error: expected initializer before '__THROW'
sighandler_t ssignal(int sig, sighandler_t handler) __THROW;
^~~~~~~
omrsig.cpp:241:42: error: expected initializer before '__THROW'
signal(int signum, sighandler_t handler) __THROW
^~~~~~~
omrsig.cpp:285:78: error: expected initializer before '__THROW'
sigaction(int signum, const struct sigaction *act, struct sigaction *oldact) __THROW
^~~~~~~
omrsig.cpp:402:1: error: '__sighandler_t' does not name a type
__sighandler_t
^~~~~~~~~~~~~~
omrsig.cpp:409:40: error: expected initializer before '__THROW'
ssignal(int sig, sighandler_t handler) __THROW
^~~~~~~
omrsig.cpp:513:36: error: expected initializer before '__THROW'
sigset(int sig, sighandler_t disp) __THROW
^~~~~~~
omrsig.cpp:716:1: error: expected '}' at end of input
}
^
omrsig.cpp:52:13: error: 'void sa_mask_to_sv_mask(const sigset_t*, int*)' declared 'static' but never defined [-Werror=unused-function]
static void sa_mask_to_sv_mask(const sigset_t *sa_mask, int *sv_mask);
^~~~~~~~~~~~~~~~~~
omrsig.cpp:53:13: error: 'void sv_mask_to_sa_mask(const int*, sigset_t*)' declared 'static' but never defined [-Werror=unused-function]
static void sv_mask_to_sa_mask(const int *sv_mask, sigset_t *sa_mask);
^~~~~~~~~~~~~~~~~~
omrsig.cpp:58:13: error: 'void sa_flags_to_sv_flags(const int*, int*)' declared 'static' but never defined [-Werror=unused-function]
static void sa_flags_to_sv_flags(const int *sa_flags, int *sv_flags);
^~~~~~~~~~~~~~~~~~~~
omrsig.cpp:59:13: error: 'void sv_flags_to_sa_flags(const int*, int*)' declared 'static' but never defined [-Werror=unused-function]
static void sv_flags_to_sa_flags(const int *sv_flags, int *sa_flags);
^~~~~~~~~~~~~~~~~~~~
omrsig.cpp:251:1: error: 'void (* omrsig_signal_internal(int, sighandler_t))(int)' defined but not used [-Werror=unused-function]
omrsig_signal_internal(int signum, sighandler_t handler)
^~~~~~~~~~~~~~~~~~~~~~