kiss_fftr for tflite application

[LakshmeeshKP]

background:
I am pretty new to zephyr.
I am working on a speech keyword detection project which uses tensorflow lite for mc. I wish to perform fft on the speech signal using kiss_fftr.h which is available at zephyrproject\optional\modules\lib\tflite-micro\third_party_static\kissfft\tools\kiss_fftr.h

How my .prj file looks:

CONFIG_CPP=y
CONFIG_STD_CPP17=y
CONFIG_TENSORFLOW_LITE_MICRO=y
CONFIG_MAIN_STACK_SIZE=2048
CONFIG_REQUIRES_FLOAT_PRINTF=y
CONFIG_REQUIRES_FULL_LIBC=y 

CONFIG_USB_DEVICE_INITIALIZE_AT_BOOT=y
CONFIG_TEST_RANDOM_GENERATOR=y

i am trying to implement it by taking inspiration from the hello_world sample project. but i am struggling to build the project.
I was mainly stuck at an error: undefined reference to kiss_fftr.h functions
i was able to get around this by modifying some .h files in kiss_fft/tools by changing C++ to C

#ifdef __cplusplus
extern "C++" {   //modified by me to "C" 
#endif

having it as "C++" didn't make sense to me, so i changed it to "C"
(not confident if i have actually fixed this part of the issue)

Now i am stuck at "multiple definitions" error:

c:/users/xyz/zephyr-sdk-0.17.2/arm-zephyr-eabi/bin/../lib/gcc/arm-zephyr-eabi/12.2.0/../../../../arm-zephyr-eabi/bin/ld.bfd.exe: modules/tflite-micro/libmodules__tflite-micro.a(kiss_fft_float.cc.obj): in function `kiss_fft_alloc':
C:/Users/xyz/zephyrproject/optional/modules/lib/tflite-micro/third_party_static/kissfft/kiss_fft.c:340: multiple definition of `kiss_fft_alloc'; app/libapp.a(kiss_fft.c.obj):C:/Users/laksh/zephyrproject/zephyr/applications/voice_tflm_test/src/kiss_fft.c:340: first defined here
c:/users/xyz/zephyr-sdk-0.17.2/arm-zephyr-eabi/bin/../lib/gcc/arm-zephyr-eabi/12.2.0/../../../../arm-zephyr-eabi/bin/ld.bfd.exe: modules/tflite-micro/libmodules__tflite-micro.a(kiss_fft_float.cc.obj): in function `kiss_fft_stride':
C:/Users/xyz/zephyrproject/optional/modules/lib/tflite-micro/third_party_static/kissfft/kiss_fft.c:372: multiple definition of `kiss_fft_stride'; 

... and so on for more functions 

I am not sure how i can fix it... Would appreciate the help alot!