Eigen library arm build problem

Autonomous Vehicles DRIVE AGX Xavier DRIVE AGX Xavier General
1

When we add the eigen library and the arm-build, then there’s some conflicting about typedef.

So I checked that

  • Eigen library(Core) include arm_neon.h when we build for arm.

  • In arm_neon.h (line:71), there’s “typedef __fp16 float16_t”

and

  • In dw/Types.h(line:84), there’s also “typedef__half float16_t”

Both libraries declare the “float16_t”. so it makes some conflict.

How to handle that problem?

My error messages are below, thank you.

/home/jw31/nvidia/nvidia_sdk/DRIVE_Software_9.0_Linux_hyperion_E3550/DriveSDK/toolchains/gcc-linaro-5.4.1/lib/gcc/aarch64-linux-gnu/5.4.1/include/arm_neon.h: At global scope:
/home/jw31/nvidia/nvidia_sdk/DRIVE_Software_9.0_Linux_hyperion_E3550/DriveSDK/toolchains/gcc-linaro-5.4.1/lib/gcc/aarch64-linux-gnu/5.4.1/include/arm_neon.h:71:16: error: conflicting declaration ‘typedef __fp16 float16_t’
typedef __fp16 float16_t;
^
In file included from /home/jw31/nvidia/nvidia_sdk/DRIVE_Software_9.0_Linux_hyperion_E3550/DriveSDK/drive-t186ref-linux/targetfs/usr/local/driveworks-2.0/targets/aarch64-Linux/include/dw/core/Context.h:49:0,
from /home/jw31/workspace/bbav/bbav-282/app/framework.hpp:4,
from /home/jw31/workspace/bbav/bbav-282/app/framework.cpp:1:
/home/jw31/nvidia/nvidia_sdk/DRIVE_Software_9.0_Linux_hyperion_E3550/DriveSDK/drive-t186ref-linux/targetfs/usr/local/driveworks-2.0/targets/aarch64-Linux/include/dw/core/Types.h:84:16: note: previous declaration as ‘typedef struct __half float16_t’
typedef __half float16_t;
^

2

Dear jw31,

It seems to be caused by a gcc version mismatch.
Can you try compiling your app on the DriveAGX, then try linking against these libs on your host machine when you are cross compiling DriveWorks applications? Thanks.

3

When I compile for opencv2, I also meet this issue.
Now I use workaround

#define float16_t opencv_broken_float16_t
#include <opencv2/opencv.hpp>
#include <opencv2/highgui.hpp>
#include <opencv2/imgproc/imgproc.hpp>
#include <cv_bridge/cv_bridge.h>
#undef float16_t
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