When compiler results are piped through a non-terminal (e.g. ninja)
the compiler disables colour diagnostics. Using `-fdiagnostics-color`
forces the compiler to enable colour output. This flag is set for
clang and gcc when `ZEPHYR_BUILD_COLOUR_DIAGNOSTIC` environment
variable is set when a clean build is started.
Signed-off-by: Arvin Farahmand <arvinf@ip-logix.com>
Without the -Wno-typedef-redefinition option, clang complains if a
typedef gets redefined in gnu99 mode (since this is officially a C11
feature).
While new versions of GCC do not seem to issue this warning in gnu99
mode anymore. So some existing code with typedef redefined which works
well with GCC will issue this warning.
Similar to what was done in 2354f055ec.
Signed-off-by: Anas Nashif <anas.nashif@intel.com>
