Bug#50409 Solaris 8 compatibility broken by assumption about

printstack() being present

When Bug#47391 was fixed, no assumption was made that support
for Solaris 8 was needed. Solaris 8 lacks printstack(), and 
the build breaks because of this.

This patch adds a test for the presence of printstack() to
configure.in for 5.0, and uses HAVE_PRINTSTACK to make
decisions rather than the __sun define.

configure.in

@@ -2128,7 +2128,7 @@ AC_CHECK_FUNCS(alarm bcmp bfill bmove bzero chsize cuserid fchmod fcntl \
   shmget shmat shmdt shmctl sigaction sigemptyset sigaddset \
   sighold sigset sigthreadmask \
   snprintf socket stpcpy strcasecmp strerror strsignal strnlen strpbrk strstr strtol \
-  strtoll strtoul strtoull tell tempnam thr_setconcurrency vidattr)
+  strtoll strtoul strtoull tell tempnam thr_setconcurrency vidattr printstack)
 
 #
 #

sql/stacktrace.c

@@ -227,7 +227,7 @@ stack trace is much more helpful in diagnosing the problem, so please do \n\
 resolve it\n");
 }
 
-#elif defined(__sun)
+#elif defined(HAVE_PRINTSTACK)
 
 /* Use Solaris' symbolic stack trace routine. */
 #include <ucontext.h>

sql/stacktrace.h

@@ -35,7 +35,7 @@ void check_thread_lib(void);
 #define HAVE_STACKTRACE
 extern void set_exception_pointers(EXCEPTION_POINTERS *ep);
 #define init_stacktrace() {}
-#elif defined(__sun)
+#elif defined(HAVE_PRINTSTACK)
 #define HAVE_STACKTRACE
 #define init_stacktrace() {}
 #endif