Teensy 3.1 Audio Shield FFT Problems

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Hi, i'm currently working on a micro audio solution. Most of the planned features are working but when i try to compile a version with FFT i always get this compiler error.

D:\Arduino_Build\fft\core.a(analyze_fft256.cpp.o): In function `AudioAnalyzeFFT256::update()':
D:\arduino-1.0.5\libraries\Audio/analyze_fft256.cpp:83: undefined reference to `arm_cfft_radix4_q15'
D:\Arduino_Build\fft\core.a(analyze_fft256.cpp.o): In function `AudioAnalyzeFFT256::init()':
D:\arduino-1.0.5\libraries\Audio/analyze_fft256.cpp:38: undefined reference to `arm_cfft_radix4_init_q15'
collect2.exe: error: ld returned 1 exit status

I'm using the i2c_t3 library instead of Wire, because i use 2 busses with different speed.
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Are you building in Arduino with Teensyduino, or with a non-Arduino makefile?

I'm guessing this is a non-Arduino build that isn't linking in the ARM math library.
First, make sure you're using at least Teensyduino version 1.19. Use Arduino's Help > About menu to check. If you have an older version, upgrade to at least 1.19. Th

If so, use File > Prefernces to turn on verbose info while compiling. That extra info is needed to troubleshoot this issue. Arduino should give you a "copy error" button to easily copy the entire output to the clipboard. Best to paste it here inside "code" tags, since it'll be long.
Was having the same issue using Eclipse Arduino plugin. Would compile in Arduino, but not in Eclipse.

Solved by adding -larm_cortexM4l_math to extra parameters to "combiner" in project properties, C/C++ Build, Settings, Arduino Combiner, Command Line Pattern. That's where I added it.
@Kig, You sir are a champ!
Thanks to you I can compile with eclipse now instead of the horrible Arduino IDE!
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