CrystaX NDK

In my code I have <alloca.h> included after , which causes the following warning to be produced:

[x86] Compile++      : test <= test.cpp
/opt/crystax-ndk-10.2.1/toolchains/x86-4.9/prebuilt/darwin-x86_64/bin/i686-linux-android-g++ -MMD -MP -MF ./obj/local/x86/objs/test/__/test.o.d -ffunction-sections -funwind-tables -no-canonical-prefixes -fstack-protector-strong -fno-exceptions -fno-rtti -O2 -g -DNDEBUG -fomit-frame-pointer -fstrict-aliasing -funswitch-loops -finline-limit=300 -I/opt/crystax-ndk-10.2.1/sources/cxx-stl/gnu-libstdc++/4.9/include -I/opt/crystax-ndk-10.2.1/sources/cxx-stl/gnu-libstdc++/4.9/libs/x86/include -I/opt/crystax-ndk-10.2.1/sources/cxx-stl/gnu-libstdc++/4.9/include/backward -Ijni -DANDROID -Wa,--noexecstack -Wformat -Werror=format-security -fexceptions -frtti -std=gnu++11 -c -I/opt/crystax-ndk-10.2.1/sources/crystax/include -I/opt/crystax-ndk-10.2.1/platforms/android-9/arch-x86/usr/include jni/../test.cpp -o ./obj/local/x86/objs/test/__/test.o
In file included from jni/../test.cpp:4:0:
/opt/crystax-ndk-10.2.1/platforms/android-9/arch-x86/usr/include/alloca.h:31:0: warning: "alloca" redefined
 #define alloca(size)   __builtin_alloca(size)
 ^
In file included from /opt/crystax-ndk-10.2.1/platforms/android-9/arch-x86/usr/include/stdlib.h:45:0,
                 from /opt/crystax-ndk-10.2.1/sources/cxx-stl/gnu-libstdc++/4.9/include/cstdlib:72,
                 from /opt/crystax-ndk-10.2.1/sources/cxx-stl/gnu-libstdc++/4.9/include/ext/string_conversions.h:41,
                 from /opt/crystax-ndk-10.2.1/sources/cxx-stl/gnu-libstdc++/4.9/include/bits/basic_string.h:2850,
                 from /opt/crystax-ndk-10.2.1/sources/cxx-stl/gnu-libstdc++/4.9/include/string:52,
                 from /opt/crystax-ndk-10.2.1/sources/cxx-stl/gnu-libstdc++/4.9/include/stdexcept:39,
                 from /opt/crystax-ndk-10.2.1/sources/cxx-stl/gnu-libstdc++/4.9/include/array:38,
                 from /opt/crystax-ndk-10.2.1/sources/cxx-stl/gnu-libstdc++/4.9/include/tuple:39,
                 from /opt/crystax-ndk-10.2.1/sources/cxx-stl/gnu-libstdc++/4.9/include/functional:55,
                 from jni/../test.cpp:1:
/opt/crystax-ndk-10.2.1/platforms/android-9/arch-x86/usr/include/crystax/freebsd/include/mangled-stdlib.h:243:0: note: this is the location of the previous definition
 #define alloca(sz) __builtin_alloca(sz)
 ^

I've created a very basic scenario to reproduce warning: https://github.com/cawka/crystax-ndk-alloca.h-bug

I'm working with CrystaX-10.2.1.