Linker errors while using ncnn with Ingenic T40

[jvasanthan]

Hi @MarsTechHAN ,

I am able to compile ncnn for Ingenic T40 and when I try to compile yolov5 example I get the following linker errors
expression.cpp:(.text+0x15ec): undefined reference to __acosf_finite' expression.cpp:(.text+0x1b0c): undefined reference to __atan2f_finite'
expression.cpp:(.text+0x1b6c): undefined reference to __fmodf_finite' expression.cpp:(.text+0x1bc4): undefined reference to __powf_finite'
expression.cpp:(.text+0x1ca8): undefined reference to `__expf_finite'

all these are related to math lib. mips uclibc doesn't support these functions.

How did you compile the examples for T40? what changes I should do to fix these errors?

Regards,
James

[nihui]

cmake -DNCNN_SIMPLEMATH=ON
may help

[jvasanthan]

Hi @nihui,

I am getting below error when I turn on NCNN_SIMPLEMATH, can I use atan2f instead of atan2?
/ncnn/src/layer/mips/msa_mathfun.h:263:15: error: 'atan2' was not declared in this scope

[nihui]

Hi @nihui,

I am getting below error when I turn on NCNN_SIMPLEMATH, can I use atan2f instead of atan2? /ncnn/src/layer/mips/msa_mathfun.h:263:15: error: 'atan2' was not declared in this scope

yeah, atan2f is fine