我有一个C程序,我想在(旧)自定义嵌入式平台上进行基准测试。问题是我只有硬件而不是工具链来编译这个平台的程序。 CPU是Atmel AT91SAM9260(ARM),运行嵌入式Linux,我可以完全访问它。 我从嵌入式系统下载了一个程序,并使用'readelf -h ...'分析其格式:
ELF Header:
Magic: 7f 45 4c 46 01 01 01 61 00 00 00 00 00 00 00 00
Class: ELF32
Data: 2's complement, little endian
Version: 1 (current)
OS/ABI: ARM
ABI Version: 0
Type: EXEC (Executable file)
Machine: ARM
Version: 0x1
Entry point address: 0x8520
Start of program headers: 52 (bytes into file)
Start of section headers: 3772 (bytes into file)
Flags: 0x602, has entry point, GNU EABI, software FP, VFP
Size of this header: 52 (bytes)
Size of program headers: 32 (bytes)
Number of program headers: 6
Size of section headers: 40 (bytes)
Number of section headers: 25
Section header string table index: 24
然后我写了以下测试程序:
#include <stdio.h>
int main() {
printf("Hello World!\n");
return(0);
}
如果我在Ubuntu 12.04(arm-linux-gnueabi-gcc test.c -o test)中使用标准ARM交叉编译器,则选择了错误的EABI(Version5 EABI而不是GNU EABI)并且它不运行在嵌入式系统上(访问权限等是正确的)。
ELF Header:
Magic: 7f 45 4c 46 01 01 01 00 00 00 00 00 00 00 00 00
Class: ELF32
Data: 2's complement, little endian
Version: 1 (current)
OS/ABI: UNIX - System V
ABI Version: 0
Type: EXEC (Executable file)
Machine: ARM
Version: 0x1
Entry point address: 0x8881
Start of program headers: 52 (bytes into file)
Start of section headers: 372148 (bytes into file)
Flags: 0x5000002, has entry point, Version5 EABI
Size of this header: 52 (bytes)
Size of program headers: 32 (bytes)
Number of program headers: 7
Size of section headers: 40 (bytes)
Number of section headers: 30
Section header string table index: 27
如果我使用像Sourcery CodeBench这样的裸机编译器,我会收到类似“未定义的引用...”的错误。这很清楚,因为缺少stdlib。我试图通过将所有lib文件从嵌入平台复制到主机来解决它,并使用“./arm-none-eabi-gcc test.c -o test -static -lc -L ./lib”进行编译。我仍然得到(相同的)未定义的引用错误。
如果工具链未知,为嵌入式系统编译C程序的最佳做法是什么?