diff --git a/Lib/pdb.py b/Lib/pdb.py
index d379d1a..e272f2e 100755
--- a/Lib/pdb.py
+++ b/Lib/pdb.py
@@ -1210,8 +1210,9 @@
         self._wait_for_mainpyfile = 1
         self.mainpyfile = self.canonic(filename)
         self._user_requested_quit = 0
-        with open(filename) as fp:
-            statement = "exec(%r)" % (fp.read(),)
+        with open(filename, "rb") as fp:
+            statement = "exec(compile(%r, %r, 'exec'))" % \
+                        (fp.read(), self.mainpyfile)
         self.run(statement)
 
 # Simplified interface
diff --git a/Misc/NEWS b/Misc/NEWS
index f412f72..8c9bb93 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -42,6 +42,8 @@
 Library
 -------
 
+- Issue #6126: Fixed pdb command-line usage.
+
 - Issue #6629: Fix a data corruption issue in the new I/O library, which could
   occur when writing to a BufferedRandom object (e.g. a file opened in "rb+" or
   "wb+" mode) after having buffered a certain amount of data for reading. This