lebedev.ri requested changes to this revision. lebedev.ri added a comment. This revision now requires changes to proceed.
In D109321#2985244 <https://reviews.llvm.org/D109321#2985244>, @peixin wrote: > The following test case fails after > https://reviews.llvm.org/rGaf000197c4214926bd7d0862d86f89aed5f20da6. > > #include <iostream> > using namespace std; > > int main() { > float a[10]; > int i, N = 10; > for (i = 0; i < N; i++) > a[i] = 0; > > #pragma omp simd > for (i = 0; i < N; i++) { > #pragma omp ordered simd > a[i] = a[i-1] + 1.0; > } > > for (i = 0; i < N; i++) > cout << a[i] << " "; > cout << endl; > } > > > > $ clang++ -fopenmp simd.cpp && ./a.out > 1 2 3 4 5 6 7 8 9 10 > $ clang++ -fopenmp -O1 simd.cpp && ./a.out > 1 1 1 1 2 1 1 1 2 3 > > It is fixed by this patch. That's UB; https://godbolt.org/z/5nb61G3vY /app/example.cpp:13:12: runtime error: index -1 out of bounds for type 'float [10]' SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior /app/example.cpp:13:12 in 1 2 3 4 5 6 7 8 9 10 Do you have an example that is miscompiled and doesn't contain UB? Repository: rG LLVM Github Monorepo CHANGES SINCE LAST ACTION https://reviews.llvm.org/D109321/new/ https://reviews.llvm.org/D109321 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
