[Buildroot] [git commit branch/2017.08.x] package/collectd: Specify FP layout based on endianness

[Buildroot] [git commit branch/2017.08.x] package/collectd: Specify FP layout based on endianness

[Peter Korsgaard]

commit: https://git.buildroot.net/buildroot/commit/?id=922497b4b9a667ff254ccbd9de23c8e18d88e4ef
branch: https://git.buildroot.net/buildroot/commit/?id=refs/heads/2017.08.x

Big-endian CPUs store floating point as big endian (at lest majority
of them do), so, in order for 'network' plugin to work correctly (and
potentially any user of htond() in collectd's codebase),
--with-fp-layout=endianflip as opposed to --with-fp-layout=nothing
needs to be specified during configuration phase.

Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Cc: Arnout Vandecappelle <arnout@mind.be>
Cc: Gustavo Zacarias <gustavo@zacarias.com.ar>
Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Reviewed-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
(cherry picked from commit bdd8475b90fa46644149d34bf852b213ec60ce71)
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
---
 package/collectd/collectd.mk | 16 +++++++++++++++-
 1 file changed, 15 insertions(+), 1 deletion(-)

diff --git a/package/collectd/collectd.mk b/package/collectd/collectd.mk
index 626fba8..6c987b2 100644
--- a/package/collectd/collectd.mk
+++ b/package/collectd/collectd.mk
@@ -24,9 +24,23 @@ COLLECTD_PLUGINS_DISABLE = \
 
 COLLECTD_CONF_ENV += LIBS="-lm"
 
+#
+# NOTE: There's also a third availible setting "intswap", which might
+# be needed on some old ARM hardware (see [2]), but is not being
+# accounted for as per discussion [1]
+#
+# [1] http://lists.busybox.net/pipermail/buildroot/2017-November/206100.html
+# [2] http://lists.busybox.net/pipermail/buildroot/2017-November/206251.html
+#
+ifeq ($(BR2_ENDIAN),"BIG")
+COLLECTD_FP_LAYOUT=endianflip
+else
+COLLECTD_FP_LAYOUT=nothing
+endif
+
 COLLECTD_CONF_OPTS += \
 	--with-nan-emulation \
-	--with-fp-layout=nothing \
+	--with-fp-layout=$(COLLECTD_FP_LAYOUT) \
 	--with-perl-bindings=no \
 	$(foreach p, $(COLLECTD_PLUGINS_DISABLE), --disable-$(p)) \
 	$(if $(BR2_PACKAGE_COLLECTD_AGGREGATION),--enable-aggregation,--disable-aggregation) \