是否有其他机制可以让预处理器做到这一点:
#define LIMIT 16
#pragma GCC unroll LIMIT
for (size_t ii = 0; ii < LIMIT; ++ii) {
...
该代码命中一个错误:
/path/to/my/file.c:100:20 error: 'LIMIT' undeclared (first use in this function)
100 | #pragma GCC unroll LIMIT
| ^~~~~
GCC documentation说,这要an integer constant expression specifying the unrolling factor
.我相信我的宏是一个"整型常量表达式",但是...
我的编译器是:riscv64-unknown-elf-gcc (g2ee5e430018) 12.2.0
.