diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 1c2642d1508..4d1c041acaa 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,5 +1,8 @@
 2017-09-04  Jakub Jelinek  <jakub@redhat.com>
 
+	* gdbhooks.py (OptMachineModePrinter.to_string): Use 8 spaces
+	instead of tab.
+
 	* lra-remat.c (reg_overlap_for_remat_p): Fix a pasto.
 
 2017-09-04  Richard Sandiford  <richard.sandiford@linaro.org>
diff --git a/gcc/gdbhooks.py b/gcc/gdbhooks.py
index 1b3f95361b6..e277121b123 100644
--- a/gcc/gdbhooks.py
+++ b/gcc/gdbhooks.py
@@ -438,8 +438,8 @@ class OptMachineModePrinter:
 
     def to_string (self):
         name = str(self.gdbval['m_mode'])
-	if name == 'E_VOIDmode':
-	    return '<None>'
+        if name == 'E_VOIDmode':
+            return '<None>'
         return name[2:] if name.startswith('E_') else name
 
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