From 696c58f9f0f2f8570c2437ad9a0b4b58a92d7346 Mon Sep 17 00:00:00 2001
From: practicalswift <practicalswift@users.noreply.github.com>
Date: Tue, 3 Nov 2015 14:11:49 +0100
Subject: [PATCH 1/2] Add test case for segfault-on-emu_stop() bug.

The following code segfaults:
unicorn.Uc(unicorn.UC_ARCH_X86, unicorn.UC_MODE_64).emu_stop()

Tested under Linux and OS X.
---
 tests/regress/segfault_on_stop.py | 13 +++++++++++++
 1 file changed, 13 insertions(+)
 create mode 100755 tests/regress/segfault_on_stop.py

diff --git a/tests/regress/segfault_on_stop.py b/tests/regress/segfault_on_stop.py
new file mode 100755
index 00000000..8d577109
--- /dev/null
+++ b/tests/regress/segfault_on_stop.py
@@ -0,0 +1,13 @@
+#!/usr/bin/env python
+
+import regress
+import unicorn
+
+
+class SegfaultOnStop(regress.RegressTest):
+    def test(self):
+        unicorn.Uc(unicorn.UC_ARCH_X86, unicorn.UC_MODE_64).emu_stop()
+        self.assertTrue(True, "If not reached, then we have a crashing bug.")
+
+if __name__ == '__main__':
+    regress.main()

From 4151d1d60087558e8adac8f01df97b25f7c4b22f Mon Sep 17 00:00:00 2001
From: practicalswift <practicalswift@users.noreply.github.com>
Date: Tue, 3 Nov 2015 14:34:31 +0100
Subject: [PATCH 2/2] Fix segfault-on-emu_stop() bug.

---
 uc.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/uc.c b/uc.c
index 00efc805..e3107b70 100644
--- a/uc.c
+++ b/uc.c
@@ -525,8 +525,10 @@ uc_err uc_emu_stop(uc_engine *uc)
         return UC_ERR_OK;
 
     uc->stop_request = true;
-    // exit the current TB
-    cpu_exit(uc->current_cpu);
+    if (uc->current_cpu) {
+        // exit the current TB
+        cpu_exit(uc->current_cpu);
+    }
 
     return UC_ERR_OK;
 }