Merge branch 'ep/malloc-check-perturb'

Fixes a brown-paper bag bug.

* ep/malloc-check-perturb:
  MALLOC_CHECK: enable it, unless disabled explicitly

t/perf/perf-lib.sh

@@ -42,7 +42,7 @@ else
 fi
 
 TEST_NO_CREATE_REPO=t
-TEST_NO_MALLOC_=t
+TEST_NO_MALLOC_CHECK=t
 
 . ../test-lib.sh
 

t/test-lib.sh

@@ -105,7 +105,7 @@ export EDITOR
 # Add libc MALLOC and MALLOC_PERTURB test
 # only if we are not executing the test with valgrind
 if expr " $GIT_TEST_OPTS " : ".* --valgrind " >/dev/null ||
-   test -n "TEST_NO_MALLOC_"
+   test -n "$TEST_NO_MALLOC_CHECK"
 then
 	setup_malloc_check () {
 		: nothing