support/cmake: impersonate a Linux system even more

Some packages test the system name to decide whether to enable/disable
features or link with specific libs.

So we forcefully set the system name form our custom system file, so
that packagses still believe they are running on Linux rather than
Buildroot.

Fixes:
    fastd      : http://autobuild.buildroot.net/results/f1d/f1dfe90068ad62e733f17a22202235415bda3974/
    paho-mqtt-c: http://autobuild.buildroot.net/results/457/457d76279e16247bf58c838a2c5dd0a4f3962c21/
    libiio     : http://autobuild.buildroot.net/results/281/2812b008a0ab6bab5fe4d45eb9ffe4e9496a8cb4/
    and so on...

Reported-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Reported-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Cc: Baruch Siach <baruch@tkos.co.il>
Cc: Ben Boeckel <mathstuf@gmail.com>
Cc: Jörg Krause <joerg.krause@embedded.rocks>
Cc: Vicente Olivert Riera <Vincent.Riera@imgtec.com>
Cc: Samuel Martin <s.martin49@gmail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

diff --git a/support/misc/Buildroot.cmake b/support/misc/Buildroot.cmake
index b0046b387b12866386701f867247f940024937bf..9f5f565255cec2306501ed57d8541cddc2864447 100644 (file)
--- a/support/misc/Buildroot.cmake
+++ b/support/misc/Buildroot.cmake
@@ -1,3 +1,7 @@
+# Impersonate a Linux system. Afterall, that's what we are...
+set(CMAKE_SYSTEM_NAME Linux)
 include(Platform/Linux)
+
+# Override problematic settings, to avoid RPATH against host lib directories.
 set_property(GLOBAL PROPERTY FIND_LIBRARY_USE_LIB32_PATHS FALSE)
 set_property(GLOBAL PROPERTY FIND_LIBRARY_USE_LIB64_PATHS FALSE)