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0 pointsaidenn02y ago0 comments

Well, what I really want is a trap on overflow, but since C doesn't support that, modern architectures don't have the capability; you can do it in software (like with ubsan), but you pay a performance penalty.

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matheusmoreira2y ago

I mentioned the -fwrapv option to make it wrap around. There's also a -ftrapv option that makes the compiler generate traps.

ndiddy2y ago

Most popular C compilers support trapping on integer overflow (i.e. https://gcc.gnu.org/onlinedocs/gcc/Code-Gen-Options.html#ind...), but it does have some overhead as it replaces the native arithmetic instruction with a call to a library function (i.e. https://gcc.gnu.org/onlinedocs/gccint/Integer-library-routin...)

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