diff --git a/lldb/packages/Python/lldbsuite/test/lldbtest.py b/lldb/packages/Python/lldbsuite/test/lldbtest.py
--- a/lldb/packages/Python/lldbsuite/test/lldbtest.py
+++ b/lldb/packages/Python/lldbsuite/test/lldbtest.py
@@ -126,6 +126,8 @@
 
 SOURCE_DISPLAYED_CORRECTLY = "Source code displayed correctly"
 
+STEP_IN_SUCCEEDED = "Thread step-in succeeded"
+
 STEP_OUT_SUCCEEDED = "Thread step-out succeeded"
 
 STOPPED_DUE_TO_EXC_BAD_ACCESS = "Process should be stopped due to bad access exception"
diff --git a/lldb/test/API/lang/c/stepping/TestThreadStepInAvoidRegexp.py b/lldb/test/API/lang/c/stepping/TestThreadStepInAvoidRegexp.py
new file mode 100644
--- /dev/null
+++ b/lldb/test/API/lang/c/stepping/TestThreadStepInAvoidRegexp.py
@@ -0,0 +1,52 @@
+"""
+Test thread step-in [ -r | --step-over-regexp ].
+"""
+
+
+
+import lldb
+import lldbsuite.test.lldbutil as lldbutil
+from lldbsuite.test.lldbtest import *
+import lldbsuite.test.lldbutil as lldbutil
+
+
+class ThreadStepInAvoidRegexTestCase(TestBase):
+
+    mydir = TestBase.compute_mydir(__file__)
+
+    def setUp(self):
+        TestBase.setUp(self)
+        self.line1 = line_number(
+            'main.c', '// frame select 2, thread step-out while stopped at "c(1)"')
+        self.line2 = line_number(
+            'main.c', '// assignment to B2')
+
+    def test_step_out_avoid_regexp(self):
+        """Exercise thread step-in -r"""
+        self.build()
+        exe = self.getBuildArtifact("a.out")
+        self.runCmd("file " + exe, CURRENT_EXECUTABLE_SET)
+
+        # Create a breakpoint inside function 'c'.
+        lldbutil.run_break_set_by_file_and_line(
+            self, "main.c", self.line1, num_expected_locations=1)
+
+        # Now run the program.
+        self.runCmd("run", RUN_SUCCEEDED)
+
+        # The process should be stopped at this point.
+        self.expect("process status", PROCESS_STOPPED,
+                    patterns=['Process .* stopped'])
+
+        # The frame #0 should correspond to main.c:40, the first line of main.
+        self.expect("thread backtrace", STOPPED_DUE_TO_BREAKPOINT,
+                    substrs=["stop reason = breakpoint"],
+                    patterns=["frame #0.*main.c:%d" % self.line1])
+
+        # Now step in, skipping the frames for 'b' and 'a'.
+        self.runCmd("thread step-in -r 'a'")
+
+        # We should be at the assignment to B2.
+        self.expect("thread backtrace", STEP_IN_SUCCEEDED,
+                    substrs=["stop reason = step in"],
+                    patterns=["frame #0.*main.c:%d" % self.line2])
diff --git a/lldb/test/API/lang/c/stepping/main.c b/lldb/test/API/lang/c/stepping/main.c
--- a/lldb/test/API/lang/c/stepping/main.c
+++ b/lldb/test/API/lang/c/stepping/main.c
@@ -39,7 +39,7 @@
 {
     int A1 = a(1); // frame select 2, thread step-out while stopped at "c(1)"
 
-    int B2 = b(2);
+    int B2 = b(2); // assignment to B2
 
     int A3 = a(3); // frame select 1, thread step-out while stopped at "c(3)"