diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index cf46c4e92b..44300d258e 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,8 @@
+2020-05-28  Simon Marchi  <simon.marchi@polymtl.ca>
+
+	* dwarf2/loc.c (class dwarf_evaluate_loc_desc)
+	<push_dwarf_reg_entry_value>: Add comment.
+
 2020-05-28  Kevin Buettner  <kevinb@redhat.com>
 	    Keith Seitz  <keiths@redhat.com>
 
diff --git a/gdb/dwarf2/loc.c b/gdb/dwarf2/loc.c
index 1aab1a4f51..400bb4d16f 100644
--- a/gdb/dwarf2/loc.c
+++ b/gdb/dwarf2/loc.c
@@ -731,6 +731,12 @@ public:
       throw_error (NO_ENTRY_VALUE_ERROR,
 		   _("Cannot resolve DW_AT_call_data_value"));
 
+    /* We are about to evaluate an expression in the context of the caller
+       of the current frame.  This evaluation context may be different from
+       the current (callee's) context), so temporarily set the caller's context.
+
+       It is possible for the caller to be from a different objfile from the
+       callee if the call is made through a function pointer.  */
     scoped_restore save_frame = make_scoped_restore (&this->frame,
 						     caller_frame);
     scoped_restore save_per_cu = make_scoped_restore (&this->per_cu,