alpha-linux-user: Fill in SI_CODE for SIGSEGV.

Signed-off-by: NRichard Henderson <rth@twiddle.net>
Signed-off-by: NAurelien Jarno <aurelien@aurel32.net>

linux-user/main.c

@@ -2433,7 +2433,8 @@ void cpu_loop (CPUState *env)
             env->lock_addr = -1;
             info.si_signo = TARGET_SIGSEGV;
             info.si_errno = 0;
-            info.si_code = 0;  /* ??? SEGV_MAPERR vs SEGV_ACCERR.  */
+            info.si_code = (page_get_flags(env->ipr[IPR_EXC_ADDR]) & PAGE_VALID
+                            ? TARGET_SEGV_ACCERR : TARGET_SEGV_MAPERR);
             info._sifields._sigfault._addr = env->ipr[IPR_EXC_ADDR];
             queue_signal(env, info.si_signo, &info);
             break;