When _PTHREADSINVARIANTS is defined SIGABRT is not included

in the set of signals to block.
Also, make the PANIC macro call abort() instead of simply
exiting.

lib/libthr/thread/thr_init.c

@@ -349,6 +349,9 @@ _thread_init(void)
 		SIGEMPTYSET(_thread_suspend_sigset);
 		SIGADDSET(_thread_suspend_sigset, SIGTHR);
 	}
+#ifdef _PTHREADS_INVARIANTS
+	SIGADDSET(_thread_suspend_sigset, SIGALRM);
+#endif
 
 	/* Get the kernel clockrate: */
 	mib[0] = CTL_KERN;

lib/libthr/thread/thr_kern.c

@@ -77,6 +77,9 @@ _thread_sigblock()
 	 */
 	SIGFILLSET(set);
 	SIGADDSET(set, SIGTHR);
+#ifdef _PTHREADS_INVARIANTS
+	SIGDELSET(set, SIGABRT);
+#endif
 
 	/* If we have already blocked signals, just up the refcount */
 	if (++curthread->signest > 1)

lib/libthr/thread/thr_private.h

@@ -60,6 +60,7 @@
 #include <spinlock.h>
 #include <stdio.h>
 #include <ucontext.h>
+#include <unistd.h>
 
 #include <machine/atomic.h>
 #include <sys/thr.h>
@@ -68,8 +69,18 @@
 /*
  * Kernel fatal error handler macro.
  */
-#define PANIC(string)   _thread_exit(__FILE__,__LINE__,string)
-
+#ifndef _PTHREADS_INVARIANTS
+#define PANIC(string)		_thread_exit(__FILE__, __LINE__, (string))
+#else /* _PTHREADS_INVARIANTS */
+#define PANIC(string)							     \
+	do {								     \
+		_thread_printf(STDOUT_FILENO, (string));		     \
+		_thread_printf(STDOUT_FILENO,				     \
+		    "\nAbnormal termination, file: %s, line: %d\n",	     \
+		    __FILE__, __LINE__);				     \
+		abort();						     \
+	} while (0)
+#endif /* !_PTHREADS_INVARIANTS */
 
 /* Output debug messages like this: */
 #define stdout_debug(args...)	_thread_printf(STDOUT_FILENO, args)