Undefined Behavior - Not what you expected
summary
A retry loop decrements an unsigned counter and then immediately dereferences a member pointer that can become null; that null pointer dereference is undefined behavior so Clang's optimizer removes the exit branch, turning the loop into an endless sequence of "connection failed" logs. The bug reproduces only with Clang (not GCC) and is visible on Godbolt; the surprising claim is that a UB after the loop lets the compiler delete the loop-exit check.
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