diff --git a/slither/core/source_mapping/source_mapping.py b/slither/core/source_mapping/source_mapping.py
index 22dabca31..422287f41 100644
--- a/slither/core/source_mapping/source_mapping.py
+++ b/slither/core/source_mapping/source_mapping.py
@@ -20,6 +20,7 @@ class SourceMapping(Context):
 
             Not done in an efficient way
         """
+        source_code = source_code.encode('utf-8')
         total_length = len(source_code)
         source_code = source_code.splitlines(True)
         counter = 0
@@ -29,17 +30,18 @@ class SourceMapping(Context):
         ending_column = None
         while counter < total_length:
             # Determine the length of the line, and advance the line number
-            lineLength = len(source_code[i])
+            line_content = source_code[i]
+            line_length = len(line_content)
             i = i + 1
 
             # Determine our column numbers.
-            if starting_column is None and counter + lineLength > start:
+            if starting_column is None and counter + line_length > start:
                 starting_column = (start - counter) + 1
-            if starting_column is not None and ending_column is None and counter + lineLength > start + length:
+            if starting_column is not None and ending_column is None and counter + line_length > start + length:
                 ending_column = ((start + length) - counter) + 1
 
             # Advance the current position counter, and determine line numbers.
-            counter += lineLength
+            counter += line_length
             if counter > start:
                 lines.append(i)
 
diff --git a/tests/source_mapping.sol b/tests/source_mapping.sol
new file mode 100644
index 000000000..771f2daed
--- /dev/null
+++ b/tests/source_mapping.sol
@@ -0,0 +1,22 @@
+contract A{
+
+    // ëëëëëëëëëëëëë这这这这这这这这这这
+
+    address unused;
+
+
+    address unused2;
+
+
+    // ই এই এই এইই এই এই এইই এই এই এই
+
+    address unused3;
+
+
+    address unused4;
+
+    // 这这这这这这这这这这这这这这这这这这这这这这这这这这这这这这这这这这这这这这这这这这这这
+    address used;
+
+
+}