[yocto][meta-gplv2][PATCH 2/2 v3] diffutils: use malloc() and realloc() from libc as-is

["Andr? Draszik" <git@andred.net>]

From: Andre' Draszik <git@andred.net>

diffutils' version of autoconf tries to run a test
program to determine if malloc() and realloc() behave
like in glibc, i.e. returning non-NULL when given 0 as
size. Running a test program doesn't work when cross-
compiling, so it defaults to assuming different
behaviour and compiles wrappers around malloc() &
realloc().

Given they behave the same in musl (these days), and
given uClibc isn't supported anymore, we can specify
the test-result, and avoid having to use diffutil's
replacement functions.

jm_cv_func_working_malloc and jm_cv_func_working_realloc
are similar to ac_cv_func_malloc_0_nonnull and
ac_cv_func_realloc_0_nonnull, which oe-core sets in
the site configuration in meta/site/, except that the
former two are the flags for the older version of
autoconf used by this package.

Signed-off-by: André Draszik <git@andred.net>

---
v3:
* update commit message
* don't make this musl specific

v2:
* switch to CACHED_CONFIGUREVARS instead of EXTRA_OECONF
---
 recipes-extended/diffutils/diffutils_2.8.1.bb | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/recipes-extended/diffutils/diffutils_2.8.1.bb b/recipes-extended/diffutils/diffutils_2.8.1.bb
index 4aad28f..7c43c4b 100644
--- a/recipes-extended/diffutils/diffutils_2.8.1.bb
+++ b/recipes-extended/diffutils/diffutils_2.8.1.bb
@@ -16,6 +16,11 @@ SRC_URI = "${GNU_MIRROR}/diffutils/diffutils-${PV}.tar.gz \
 SRC_URI[md5sum] = "71f9c5ae19b60608f6c7f162da86a428"
 SRC_URI[sha256sum] = "c5001748b069224dd98bf1bb9ee877321c7de8b332c8aad5af3e2a7372d23f5a"
 
+CACHED_CONFIGUREVARS = "\
+    jm_cv_func_working_malloc=yes \
+    jm_cv_func_working_realloc=yes \
+"
+
 do_configure_prepend () {
 	chmod u+w ${S}/po/Makefile.in.in
 }
-- 
2.23.0.rc1