Re: [PATCH] [COMMITTED] Fix PR gdb/17820

[Pedro Alves <palves@redhat.com>]

Hi Patrick,

I noticed that the buildbots are showing that this new test is failing:

 https://sourceware.org/ml/gdb-testers/2015-q2/msg04164.html

~~~
============================
new FAIL: gdb.base/gdbinit-history.exp: show commands <<2>>
new FAIL: gdb.base/gdbinit-history.exp: show history size
new FAIL: gdb.base/gdbinit-history.exp: show history size <<2>>
~~~

Logs at:

 http://gdb-build.sergiodj.net/cgit/Fedora-x86_64-m64/.git/tree/?h=master&id=aa0e3e6cdb70d805ec9a3c689861d936ab9c5c90

 (follow the "plain" link on the right right)

Then I noticed that the test is also failing on my
machine (F20).  :-)  I went ahead and wrote a fix.  What do
you think?

-------
From d75f038583bfa6265253e389c1012dc29eabd208 Mon Sep 17 00:00:00 2001
From: Pedro Alves <palves@redhat.com>
Date: Fri, 15 May 2015 16:47:23 +0100
Subject: [PATCH] Fix gdb.base/gdbinit-history.exp when HISTSIZE is set in the
 environment

Some buildslaves are showing that this test is failing.  E.g.,:

 https://sourceware.org/ml/gdb-testers/2015-q2/msg04164.html

The issue is that HISTSIZE is set to 1000 in the environment that runs
the tests (that's the default in Fedora, set in /etc/profile).

We can trivially reproduce it with:

 $ HISTSIZE=1000 make check RUNTESTFLAGS="gdbinit-history.exp"
 (...)
 Running /home/pedro/gdb/mygit/src/gdb/testsuite/gdb.base/gdbinit-history.exp ...
 FAIL: gdb.base/gdbinit-history.exp: show history size
 FAIL: gdb.base/gdbinit-history.exp: show history size
 FAIL: gdb.base/gdbinit-history.exp: show commands

gdb.log shows:
 ...
 (gdb) set height 0
 (gdb) set width 0
 (gdb) show history size
 The size of the command history is 1000.
 (gdb) FAIL: gdb.base/gdbinit-history.exp: show history size

gdb/testsuite/ChangeLog:
2015-05-15  Pedro Alves  <palves@redhat.com>

	* gdb.base/gdbinit-history.exp (test_gdbinit_history_setting):
	Unset HISTSIZE in the environment while testing and restore
	afterwards.
---
 gdb/testsuite/gdb.base/gdbinit-history.exp | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/gdb/testsuite/gdb.base/gdbinit-history.exp b/gdb/testsuite/gdb.base/gdbinit-history.exp
index 474680a..7513934 100644
--- a/gdb/testsuite/gdb.base/gdbinit-history.exp
+++ b/gdb/testsuite/gdb.base/gdbinit-history.exp
@@ -29,6 +29,17 @@ proc test_gdbinit_history_setting { home size } {
 
     set old_home $env(HOME)
     set env(HOME) "$srcdir/$subdir/$home"
+
+    # The HISTSIZE environment variable takes precedence over whatever
+    # history size is set in .gdbinit.  Make sure the former is not
+    # set.
+    set have_old_histsize 0
+    if [info exists env(HISTSIZE)] {
+	set old_histsize $env(HISTSIZE)
+	unset env(HISTSIZE)
+	set have_old_histsize 1
+    }
+
     set saved_internal_gdbflags $INTERNAL_GDBFLAGS
     set INTERNAL_GDBFLAGS [string map {"-nx" ""} $INTERNAL_GDBFLAGS]
 
@@ -44,6 +55,11 @@ proc test_gdbinit_history_setting { home size } {
     }
 
     set INTERNAL_GDBFLAGS $saved_internal_gdbflags
+
+    if {$have_old_histsize} {
+	set env(HISTSIZE) $old_histsize
+    }
+
     set $env(HOME) $old_home
 }
 
-- 
1.9.3