>- When compiling user programs and required libraries, add the option **-funwind-tables -rdynamic -g** for stack backtracking.
>- The **-mfloat-abi=softfp**, **-mcpu=cortex-a7**, and **-mfpu=neon-vfpv4** options specify the floating-point calculation optimization, chip architecture, and FPU, which must be the same as the compilation options used by the libc library. Otherwise, the libc library file cannot be found during the link time.
>- **-target arm-liteos** specifies the path of the library files related to the compiler.
>- **--sysroot=/home/<user-name\>/harmony/out/hispark\_taurus/ipcamera\_hispark\_taurus/sysroot** specifies the root directory of the compiler library files. In this example, the OpenHarmony project code is stored in **/home/<user-name\>/harmony**. The **out/hispark\_taurus/ipcamera\_hispark\_taurus** directory indicates the product specified by the **hb set** command during compilation. In this example, **ipcamera\_hispark\_taurus** is the product specified.
>- **--sysroot=/home/<user-name\>/directory/out/hispark\_taurus/ipcamera\_hispark\_taurus/sysroot** specifies the root directory of the compiler library files. In this example, the OpenHarmony project code is stored in **/home/<user-name\>/directory**. The **out/hispark\_taurus/ipcamera\_hispark\_taurus** directory indicates the product specified by the **hb set** command during compilation. In this example, **ipcamera\_hispark\_taurus** is the product specified.
>- **$\(clang -mfloat-abi=softfp -mcpu=cortex-a7 -mfpu=neon-vfpv4 -target arm-liteos -print-file-name=libunwind.a\)** specifies the path of the unwind library.