When stepping into a native function (or block) with a jstring variable which contains a local reference, the debuggee crashes with a segfault (art_sigsegv_fault). It appears that the pointer contained in the jstring is invalid (low address) but the debugger tries to dereference it anyway. When not stepping into such block (for example, resuming program before the block, or setting a breakpoint after the block containing the jstring - where the variable is no longer defined) no crash occurs.
I have reproduced this with function arguments and local variables.

Steps to repro - based on "Empty Activity" template with C++ support:

Native code:
extern "C" JNIEXPORT void JNICALL
Java_com_example_jnibugrepro_MainActivity_stringToJNI(
JNIEnv *env,
jobject /* this */,
jstring str) {
const char *chars = env->GetStringUTFChars(str, nullptr); // Setting a breakpoint here will trigger the crash
env->ReleaseStringUTFChars(str, chars);
}

Java code:

package com.example.jnibugrepro;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;

public class MainActivity extends AppCompatActivity {
static {
System.loadLibrary("native-lib");
}

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);

stringToJNI("test");
}

public native void stringToJNI(String s);
}

Build: 3.2.1, AI-181.5540.7.32.5056338, 201810090144,

AI-181.5540.7.32.5056338, JRE 1.8.0_152-release-1136-b06x64 JetBrains s.r.o, OS Windows 10(amd64) v10.0 , screens 1536x864

Android Gradle Plugin: 3.2.1
Gradle: 4.6
NDK: from local.properties: 18.1.5063045; latest from SDK: 18.1.5063045;
LLDB: LLDB 3.1 (revision: 3.1.4508709)
CMake: from local.properties: (not specified); latest from SDK: 3.6.0-rc2; from PATH: (not found);

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