Non-local jump in C language signal processing program?

refer to Exceptions in C with Longjmp and Setjmp to write the following program:

-sharpinclude <setjmp.h>
-sharpinclude <signal.h>
-sharpinclude <stdio.h>

jmp_buf ex_buf__;

-sharpdefine TRY do{ if(!setjmp(ex_buf__)) {
-sharpdefine CATCH } else {
-sharpdefine ETRY } } while(0)
-sharpdefine THROW longjmp(ex_buf__, 1)

void sigint_handler(int sig) {
  THROW;
}


int main(void) {
  if (signal(SIGINT, sigint_handler) == SIG_ERR) {
    return 0;
  }

  TRY {
    while (1) {
      printf("Run...\r");
    }
    /* raise(SIGINT); */
  } CATCH {
    printf("KeyboardInterrupt");
  }
  ETRY;

  return 0;
}

originally hoped that when the program was running, pressing Ctrl-C would get the output: KeyboardInterrupt .

however, the program crashes at actual run time. The output before the crash is still Run. .

if you replace the while part with raise (SIGINT) , you can get the desired result.

Why is this? Does it have anything to do with the endless cycle?

compilation environment:

Compiler:

gcc version 7.2.0 (x86_64-win32-seh-rev1, Built by MinGW-W64 project)

clang version 5.0.1 (tags/RELEASE_501/final)
Target: x86_64-pc-windows-msvc
Thread model: posix

the result of the two runs is the same.

operating system:
```
Microsoft Windows 7
```

C windows

Mar.23,2021

-sharpinclude <setjmp.h> -sharpinclude <signal.h> -sharpinclude <stdio.h> jmp_buf ex_buf__; void sigint_handler(int sig) { __builtin_longjmp(ex_buf__, 1); } int main(void) { if (signal(SIGINT, sigint_handler) == SIG_ERR) { return 0; } if (!__builtin_setjmp(ex_buf__)) { while (1) { printf("Run...\r"); } } else { // print() fprintf(stdout, ...) fprintf(stderr, "KeyboardInterrupt\n"); } return 0; }