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Hi Zoltan, We've come across this before where people meant to induce a trap by dereferencing a null. It doesn't work for LLVM (as you found out). Essentially, it's a valid transformation to turn this into unreachable. The better solution is to use something like __builtin_trap. -bw On Sep 5, 2009, at 2:19 PM, Zoltan Varga <vargaz at gmail.com> wrote: > >

Hi, Currently, llvm treats the loads from a null address as unreachable code, i.e.: load i32* null is transformed by some optimization pass into unreachable This presents problems in JIT compilers like mono which implement null pointer checks by trapping SIGSEGV signals. It also looks incorrect since it changes program behavior, which might be undefined in general, but it is quite

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