fixed inclusion of limits.h when building with newlib

The -nostdinc flag to GCC makes it not include its own directories when
searching headers, which means they need to be added manually. The same
Makefile line (~657) that adds the -nostdinc is also adding the correct path
for the gcc used to build, using the "-print-file-name=include" switch to get
the correct path for the respective gcc version.

The problem is that including limits.h from newlib will try to include gcc's
version too, which in every toolchain the SDK provides (and at least on my
machine, the same thing applies for the system gcc), limits.h is found under
gcc's "include-fixed" directory, not just include. So another -isystem should
be added with the value from "-print-file-name=include-fixed".

Jira: ZEP-142
Credits: Iván Briano
Change-Id: I33b7d9808d000a7346df4f88df92dc76e31fb2dc
Signed-off-by: Anas Nashif <anas.nashif@intel.com>
1 file changed