HLS4ML/vivado HLS 报错解决方案

用HLS4ML到 hls_model.build()的时候报错
报错内容

/opt/Xilinx/Vivado/2019.1/include/mpfr.h:724:28: error: ‘mpfr_srcptr’ was not declared in this scope
 __MPFR_DECLSPEC int    mpfr_custom_get_kind   _MPFR_PROTO ((mpfr_srcptr));
                            ^~~~~~~~~~~
make: *** [obj/myproject.cpp_pre.cpp.tb.o] Error 1
ERROR: [COSIM 212-317] C++ compile error.
ERROR: [COSIM 212-321] EXE file generate failed.
ERROR: [COSIM 212-321] EXE file generate failed.
ERROR: [COSIM 212-331] Aborting co-simulation: C simulation failed, compilation errors.
ERROR: [COSIM 212-5] *** C/RTL co-simulation file generation failed. ***
ERROR: [COSIM 212-4] *** C/RTL co-simulation finished: FAIL ***
command 'ap_source' returned error code
    while executing
"source build_prj.tcl"
    ("uplevel" body line 1)
    invoked from within
"uplevel \#0 [list source $arg] "

INFO: [HLS 200-112] Total elapsed time: 578.3 seconds; peak allocated memory: 1.226 GB.
INFO: [Common 17-206] Exiting vivado_hls at Tue Dec 14 15:45:32 2021...
child process exited 

原因是因为GCC文件冲突，这里用的是vivado2019.2
解决方案：

1. 把/tools/Xilinx/Vivado/2019.2/include/mpfr.h 中系统导入头文件<gmp.h> 改为当前文件夹导入”gmp.h“

#ifndef __GMP_H__
#include "gmp.h"
#endif

2. 在每个源文件（main.cpp和test.cpp，主文件路径在my-hls-test/fireware/myproject.cpp，test文件在my-hls-test/fmyproject_test.cpp）头顶添加下面语句,这句话添加的位置靠前点儿

#include "/tools/Xilinx/Vivado/2019.2/include/gmp.h"
#define __gmp_const const

这个bug需要在每次生成my-hls-test文件夹之后手动修改cpp文件，因此不能在python文件中直接用hls_model.build()，需要命令行输入
hls4ml build -p my-hls-test -a

参考：

1. https://chhzh123.github.io/blogs/2020-03-11-vivado-hls/
2. https://support.xilinx.com/s/question/0D52E00006iHkfpSAC/vivado-20153-hls-bug-gmph?language=en_US
3. https://github.com/fastmachinelearning/hls4ml/issues/473
4. https://fastmachinelearning.org/hls4ml/command.html