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A comment on Undefined behavior in C is a reading error. Parent comment

Re:Undefined behavior in C is a reading error by rectang on Thursday May 20, 2021 @10:06PM (#27229745)
> most compilers provide a choice (-fwrapv, -fno-strict-aliasing, ...). Yet few projects use these options,

Even if you opt into those (and the projects I've been involved with have), the precedent is established: when new compiler optimizations are introduced with disruptive semantics, they are opt-out, not opt-in — a fail-dangerous failure mode.

> Doesn't that indicate that C programmers indeed want to sacrifice safety for optimizations?

Maybe so. Which is one reason I wouldn't call myself a "C programmer" any more. The demands to program responsibly in C are absurdly high.

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Re:Undefined behavior in C is a reading error by account42 on Friday May 21, 2021 @08:05AM (#27232974)
> Even if you opt into those (and the projects I've been involved with have), the precedent is established: when new compiler optimizations are introduced with disruptive semantics, they are opt-out, not opt-in — a fail-dangerous failure mode.

Actually, the default for gcc is -O0. You are opting in with -O2 etc.

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