Clang: how to force crash/exception of runtime error due to -fsanitize=undefined

I just watched an interesting talk on UB and I tried out some things.

Consider the following code:

#include <limits.h>
#include <stdio.h>

int f(int x) {
    return x + 10;
}

int main(void) {
    int i;
    i = INT_MAX - 3;

    printf("i = %d\n",i);
    printf("f(%d) = %d\n",i,f(i));

    printf("Hello World\n");

    return 0;
}

When compiling using:

clang -O0 -fsanitize=undefined a.c

And then running the programm, there will occur a runtime error and clang will explain in detail what’s wrong:

runtime error: signed integer overflow: 2147483644 + 10 cannot be represented in type 'int'

However, the programm will continue past the offending line and execute the Hello World message, and the exit status / return code will be 0, as if nothing bad has happened.

My question is:

How do I force a hard crash / exception (like an assert() error) in my C programm when that happens using clang?

Thanks for any helpful answers in advance.

PS: I learned that the error message cannot be produced in compile time, only during runtime, but I didn’t expect that the consequences were so loose when enabling -fsanitize=undefined.

Expectations:

clang -O0 -fsanitize=undefined a.c -o a.out
./a.out
echo $?

• Hello World does not appear
• exit status is != 0

>Solution :

https://clang.llvm.org/docs/UndefinedBehaviorSanitizer.html

For most checks (checks), the instrumented program prints a verbose
error report and continues execution upon a failed check. You can use
the following options to change the error reporting behavior:

• -fno-sanitize-recover=...: print a verbose error report and exit the program;

• -fsanitize-trap=...: execute a trap instruction (doesn’t require UBSan run-time support). If the signal is not caught, the program will
  typically terminate due to a SIGILL or SIGTRAP signal.

It sounds like you want to use -fsanitize=undefined -fno-sanitize-recover=all.