[Bug c++/102854] New: [OpenMP] Bogus "initializer expression refers to iteration variable" when using templates

[burnus at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102854

            Bug ID: 102854
           Summary: [OpenMP] Bogus "initializer expression refers to
                    iteration variable" when using templates
           Product: gcc
           Version: 12.0
            Status: UNCONFIRMED
          Keywords: openmp, rejects-valid
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: burnus at gcc dot gnu.org
                CC: jakub at gcc dot gnu.org
  Target Milestone: ---

The following code compiles with the "typedef" but fails when used as
"template" with:

fooc.c:9:3: error: initializer expression refers to iteration variable ‘i’
    9 |   for (IndexType i = 0; i < N; ++i)
      |   ^~~

Long version:
https://github.com/SOLLVE/sollve_vv/blob/master/tests/5.0/application_kernels/lsms_triangular_packing.cpp

[Side note: According to the notes in the Pull Request #225, it works with LLVM
13 but fails with LLVM 11 and 12.]

Reduceted testcase:

// typedef IndexType int;  // < works:
template <typename IndexType>  // < fails
void
foo (IndexType N, IndexType M)
{
  #pragma omp target teams distribute parallel for collapse(2)
  for (IndexType i = 0; i < N; ++i)
    for (IndexType k = i; k < M; ++k)
      ;
}