Have you seen this page?
Posted May 25, 2011 5:12 UTC (Wed) by khim
In reply to: Sure, but then you deserve what you get...
Parent article: What Every C Programmer Should Know About Undefined Behavior #3/3
How would gcc, a C program, compute the result of a signed overflow without risking crashing?
Have you seen this page? Specifically the libraries part? Do you know why GMP, MPFR and MPC are requirements, not options? Actually I think this particular optimization does not use multiprecision arithmetic, but if it's needed in some passes it is available to GCC despite the fact that it's C program.
P.S. Note that is you really want "overflow", not "undefined behavior" you can do that and the fact that GCC is a C program does not stop you.
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