code review 906041: runtime: turn divide by zero, nil dereference into panics

src/pkg/runtime/freebsd/signals.h

 // Copyright 2009 The Go Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
 #define C SigCatch
 #define I SigIgnore
 #define R SigRestart
 #define Q SigQueue
+#define P SigPanic
 
-static SigTab sigtab[] = {
+SigTab sigtab[] = {
         /* 0 */         0, "SIGNONE: no trap",
         /* 1 */         Q+R, "SIGHUP: terminal line hangup",
         /* 2 */         Q+R, "SIGINT: interrupt",
         /* 3 */         C, "SIGQUIT: quit",
         /* 4 */         C, "SIGILL: illegal instruction",
         /* 5 */         C, "SIGTRAP: trace trap",
         /* 6 */         C, "SIGABRT: abort",
         /* 7 */         C, "SIGEMT: EMT instruction",
-        /* 8 */         C, "SIGFPE: floating-point exception",
+        /* 8 */         C+P, "SIGFPE: floating-point exception",
         /* 9 */         0, "SIGKILL: kill",
-        /* 10 */        C, "SIGBUS: bus error",
-        /* 11 */        C, "SIGSEGV: segmentation violation",
+        /* 10 */        C+P, "SIGBUS: bus error",
+        /* 11 */        C+P, "SIGSEGV: segmentation violation",
         /* 12 */        C, "SIGSYS: bad system call",
         /* 13 */        I, "SIGPIPE: write to broken pipe",
         /* 14 */        Q+I+R, "SIGALRM: alarm clock",
         /* 15 */        Q+R, "SIGTERM: termination",
         /* 16 */        Q+I+R, "SIGURG: urgent condition on socket",
         /* 17 */        0, "SIGSTOP: stop, unblockable",
         /* 18 */        Q+I+R, "SIGTSTP: stop from tty",
         /* 19 */        0, "SIGCONT: continue",
         /* 20 */        Q+I+R, "SIGCHLD: child status has changed",
         /* 21 */        Q+I+R, "SIGTTIN: background read from tty",
         /* 22 */        Q+I+R, "SIGTTOU: background write to tty",
         /* 23 */        Q+I+R, "SIGIO: i/o now possible",
         /* 24 */        Q+I+R, "SIGXCPU: cpu limit exceeded",
         /* 25 */        Q+I+R, "SIGXFSZ: file size limit exceeded",
         /* 26 */        Q+I+R, "SIGVTALRM: virtual alarm clock",
         /* 27 */        Q+I+R, "SIGPROF: profiling alarm clock",
         /* 28 */        Q+I+R, "SIGWINCH: window size change",
         /* 29 */        Q+I+R, "SIGINFO: information request",
         /* 30 */        Q+I+R, "SIGUSR1: user-defined signal 1",
         /* 31 */        Q+I+R, "SIGUSR2: user-defined signal 2",
         /* 32 */        Q+I+R, "SIGTHR: reserved",
 };
 #undef C
 #undef I
 #undef R
 #undef Q
+#undef P
 
 #define NSIG 33