[PATCH] tests: avoid false positive valgrind failures

[Pádraig Brady]

* init.cfg (require_valgrind_): Check the `true` program,
which will check more valgrind failure cases as now
detailed in the function comments.
---
 init.cfg |    8 ++++++--
 1 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/init.cfg b/init.cfg
index e853b0a..64f63cb 100644
--- a/init.cfg
+++ b/init.cfg
@@ -159,10 +159,14 @@ require_strace_()
   fi
 }
 
-# Skip the current test if valgrind doesn't work.
+# Skip the current test if valgrind doesn't work,
+# which could happen if not installed,
+# or hasn't support for the built architecture,
+# or hasn't appropriate error suppressions installed etc.
 require_valgrind_()
 {
-  valgrind --help >/dev/null || skip_ "requires valgrind"
+  valgrind --error-exitcode true 2>/dev/null ||
+    skip_ "requires a working valgrind"
 }
 
 require_setfacl_()
-- 
1.7.6.4