diff --git a/gdb/testsuite/ChangeLog b/gdb/testsuite/ChangeLog
index 9b446afb384..a74ac524d2c 100644
--- a/gdb/testsuite/ChangeLog
+++ b/gdb/testsuite/ChangeLog
@@ -1,3 +1,10 @@
+2015-05-19  Pedro Alves  <palves@redhat.com>
+
+	* gdb.base/gdbinit-history.exp (test_gdbinit_history_setting):
+	Save the whole env array instead of just HOME.  Unset HISTSIZE in
+	the environment while testing.  Restore whole environment
+	afterwards.
+
 2015-05-16  Doug Evans  <xdje42@gmail.com>
 
 	* gdb.guile/scm-ports.c: New file.
diff --git a/gdb/testsuite/gdb.base/gdbinit-history.exp b/gdb/testsuite/gdb.base/gdbinit-history.exp
index 474680a7e13..aba15b45158 100644
--- a/gdb/testsuite/gdb.base/gdbinit-history.exp
+++ b/gdb/testsuite/gdb.base/gdbinit-history.exp
@@ -27,8 +27,15 @@ proc test_gdbinit_history_setting { home size } {
     global srcdir
     global subdir
 
-    set old_home $env(HOME)
+    array set old_env [array get env]
+
     set env(HOME) "$srcdir/$subdir/$home"
+
+    # The HISTSIZE environment variable takes precedence over whatever
+    # history size is set in .gdbinit.  Make sure the former is not
+    # set.
+    unset -nocomplain env(HISTSIZE)
+
     set saved_internal_gdbflags $INTERNAL_GDBFLAGS
     set INTERNAL_GDBFLAGS [string map {"-nx" ""} $INTERNAL_GDBFLAGS]
 
@@ -44,7 +51,8 @@ proc test_gdbinit_history_setting { home size } {
     }
 
     set INTERNAL_GDBFLAGS $saved_internal_gdbflags
-    set $env(HOME) $old_home
+
+    array set env [array get old_env]
 }
 
 test_gdbinit_history_setting "gdbinit-history/unlimited" "unlimited"