[PATCH] tests: change misc/printf-surprise so that it doesn't segfault anymore

[Jim Meyering]

Now that I know the cause, I've worked around it:

>From b3e779c090bd6b3ebbd2e811b71891261ce85a9c Mon Sep 17 00:00:00 2001
From: Jim Meyering <address@hidden>
Date: Sun, 16 Nov 2008 09:53:48 +0100
Subject: [PATCH 1/2] tests: change misc/printf-surprise so that it doesn't 
segfault anymore

* tests/misc/printf-surprise: Disable MALLOC_PERTURB_, so that "make
check" no longer provokes a segfault from printf(1).  Before, that
would be detected as a known problem and cause the test to be skipped.
Adjust the test so that a segfault once again results in test failure.
---
 tests/misc/printf-surprise |   11 ++++++++---
 1 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/tests/misc/printf-surprise b/tests/misc/printf-surprise
index b24e3be..34f6864 100755
--- a/tests/misc/printf-surprise
+++ b/tests/misc/printf-surprise
@@ -54,6 +54,10 @@ fail=0

 mkfifo fifo || framework_failure

+# Disable MALLOC_PERTURB_, to avoid triggering this bug
+# http://bugs.debian.org/481543#77
+export MALLOC_PERTURB_=0
+
 head -c 10 fifo > out &
 ( ulimit -v 10000; env $prog %20000000f 0 2>err-msg > fifo )
 exit=$?
@@ -78,9 +82,10 @@ case $n_out:$diagnostic:$exit in
   10:n:0) ;; # ok, succeeds w/no diagnostic: FreeBSD 6.1
   0:y:1)  ;; # ok, glibc-2.8 and newer, when printf(3) fails with ENOMEM

-  *:139)     # segfault; known bug at least in debian unstable's libc6 2.7-11
-     echo 1>&2 "$0: bug in snprintf causes low-mem use of printf to segfault"
-     fail=77;;
+  # With MALLOC_PERTURB_=0, this no longer happens.
+  # *:139)     # segfault; known bug at least in debian unstable's libc6 2.7-11
+  #    echo 1>&2 "$0: bug in snprintf causes low-mem use of printf to segfault"
+  #    fail=77;;

   # 10:y) ;; # Fail: doesn't happen: nobody succeeds with a diagnostic
   # 0:n)  ;; # Fail pre-patch: no output, no diag
--
1.6.0.4.983.ga2771