Undefined compiler behaviour or a compiler bug?
Hans Petter Selasky
hps at selasky.org
Thu Apr 29 21:12:54 UTC 2021
On 4/29/21 11:06 PM, Hans Petter Selasky wrote:
> Can someone please explain what C-compiler flag I'm missing, to make
> this simple C-program terminate?
> I have a function _abs() which at some point is equal to one, but the
> compiler thinks it is not required to emit the test for the while() at
> all, looking at the assembly code! A printf() clearly verifies that the
> _abs() function has returned one.
> clang11 -O2 test.c && ./a.out
Looks like -fwrapv fixes the issue.
Sorry for the noise.
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