GCC Errors

C:\Users\MyName\Desktop>gcc -O3 peter.c -o peter.exe
peter.c:10:18: error: '__int128' is not supported for this target
 typedef unsigned __int128 scalar;
                  ^
peter.c:23:23: error: unknown type name 'siginfo_t'
 void handler(int sig, siginfo_t *siginfo, void *context) {
                       ^
peter.c: In function 'main':
peter.c:30:22: error: storage size of 'act' isn't known
     struct sigaction act;
                      ^
peter.c:32:25: error: 'handler' undeclared (first use in this function)
     act.sa_sigaction = &handler;
                         ^
peter.c:32:25: note: each undeclared identifier is reported only once for each function it appears in
peter.c:33:20: error: 'SA_SIGINFO' undeclared (first use in this function)
     act.sa_flags = SA_SIGINFO;
                    ^
peter.c:37:5: warning: left shift count >= width of type [enabled by default]
     const scalar L = ((scalar)0xc9f2c9cd0UL << 64) + 0x4674edea40000000UL;
     ^
peter.c:38:5: warning: left shift count >= width of type [enabled by default]
     const scalar T = (scalar)1 << 64;   // used in an anti-overflow test
     ^
peter.c:69:13: warning: right shift count >= width of type [enabled by default]
             printf("Sides: 0x%016"PRIx64"%016"PRIx64, (uint64_t)(x >> 64), (uint64_t)x);
             ^
peter.c:70:13: warning: right shift count >= width of type [enabled by default]
             printf(", 0x%016"PRIx64"%016"PRIx64, (uint64_t)(y >> 64), (uint64_t)y);
             ^
peter.c:71:13: warning: right shift count >= width of type [enabled by default]
             printf(", 0x%016"PRIx64"%016"PRIx64, (uint64_t)(z >> 64), (uint64_t)z);
             ^
peter.c:72:13: warning: right shift count >= width of type [enabled by default]
             printf("; diags 0x%016"PRIx64"%016"PRIx64, (uint64_t)(u >> 64), (uint64_t)u);
             ^
peter.c:73:13: warning: right shift count >= width of type [enabled by default]
             printf(", 0x%016"PRIx64"%016"PRIx64, (uint64_t)(v >> 64), (uint64_t)v);
             ^
peter.c:74:13: warning: right shift count >= width of type [enabled by default]
             printf(", 0x%016"PRIx64"%016"PRIx64"\n", (uint64_t)(w >> 64), (uint64_t)w);
             ^
peter.c:90:21: warning: right shift count >= width of type [enabled by default]
                     printf("Sides: 0x%016"PRIx64"%016"PRIx64, (uint64_t)(xc >> 64), (uint64_t)xc);
                     ^
peter.c:91:21: warning: right shift count >= width of type [enabled by default]
                     printf(", 0x%016"PRIx64"%016"PRIx64, (uint64_t)(yc >> 64), (uint64_t)yc);
                     ^
peter.c:92:21: warning: right shift count >= width of type [enabled by default]
                     printf(", 0x%016"PRIx64"%016"PRIx64, (uint64_t)(zc >> 64), (uint64_t)zc);
                     ^
peter.c:93:21: warning: right shift count >= width of type [enabled by default]
                     printf("; diags 0x%016"PRIx64"%016"PRIx64, (uint64_t)(uc >> 64), (uint64_t)uc);
                     ^
peter.c:94:21: warning: right shift count >= width of type [enabled by default]
                     printf(", 0x%016"PRIx64"%016"PRIx64, (uint64_t)(vc >> 64), (uint64_t)vc);
                     ^
peter.c:95:21: warning: right shift count >= width of type [enabled by default]
                     printf(", 0x%016"PRIx64"%016"PRIx64"\n", (uint64_t)(wc >> 64), (uint64_t)wc);
                     ^